Randolph, IA Natural Disasters and Weather Extremes
Hot Rankings
The chance of earthquake damage in Randolph is about the same as Iowa average and is much lower than the national average. The risk of tornado damage in Randolph is higher than Iowa average and is much higher than the national average.
Earthquake Index, #133
| Randolph, IA | 0.01 |
| Iowa | 0.00 |
| U.S. | 1.81 |
The earthquake index value is calculated based on historical earthquake events data using USA.com algorithms. It is an indicator of the earthquake level in a region. A higher earthquake index value means a higher chance of an earthquake.
Volcano Index, #1
| Randolph, IA | 0.0000 |
| Iowa | 0.0000 |
| U.S. | 0.0023 |
The volcano index value is calculated based on the currently known volcanoes using USA.com algorithms. It is an indicator of the possibility of a region being affected by a possible volcano eruption. A higher volcano index value means a higher chance of being affected.
Tornado Index, #311
| Randolph, IA | 253.80 |
| Iowa | 236.74 |
| U.S. | 136.45 |
The tornado index value is calculated based on historical tornado events data using USA.com algorithms. It is an indicator of the tornado level in a region. A higher tornado index value means a higher chance of tornado events.
Other Weather Extremes Events
A total of 4,127 other weather extremes events within 50 miles of Randolph, IA were recorded from 1950 to 2010. The following is a break down of these events:
| Type | Count | Type | Count | Type | Count | Type | Count | Type | Count |
| Avalanche: | 0 | Blizzard: | 36 | Cold: | 79 | Dense Fog: | 0 | Drought: | 5 |
| Dust Storm: | 0 | Flood: | 382 | Hail: | 1,814 | Heat: | 19 | Heavy Snow: | 31 |
| High Surf: | 0 | Hurricane: | 0 | Ice Storm: | 21 | Landslide: | 0 | Strong Wind: | 80 |
| Thunderstorm Winds: | 1,421 | Tropical Storm: | 0 | Wildfire: | 0 | Winter Storm: | 88 | Winter Weather: | 11 |
| Other: | 140 | ||||||||
Volcanos Nearby
No volcano is found in or near Randolph, IA.
Historical Earthquake Events
No historical earthquake events that had recorded magnitudes of 3.5 or above found in or near Randolph, IA.
No historical earthquake events found in or near Randolph, IA.
Historical Tornado Events
A total of 94 historical tornado events that had recorded magnitude of 2 or above found in or near Randolph, IA.
| Distance (miles) | Date | Magnitude | Start Lat/Log | End Lat/Log | Length | Width | Fatalities | Injuries | Property Damage | Crop Damage | Affected County |
| 0.8 | 1990-06-13 | 2 | 40°52'N / 95°39'W | 40°53'N / 95°27'W | 10.50 Miles | 67 Yards | 0 | 0 | 250K | 0 | Fremont |
| 5.8 | 1964-06-22 | 3 | 40°45'N / 95°36'W | 40°50'N / 95°29'W | 8.00 Miles | 400 Yards | 0 | 0 | 250K | 0 | Fremont |
| 7.2 | 1979-08-28 | 3 | 40°52'N / 95°40'W | 40°41'N / 95°22'W | 19.90 Miles | 533 Yards | 2 | 14 | 2.5M | 0 | Fremont |
| 8.0 | 1979-08-28 | 3 | 40°55'N / 95°46'W | 40°52'N / 95°40'W | 5.60 Miles | 533 Yards | 0 | 0 | 3K | 0 | Mills |
| 9.6 | 1964-04-20 | 2 | 40°54'N / 95°23'W | 0 | 1 | 250K | 0 | Montgomery | |||
| 9.8 | 1964-04-20 | 2 | 40°45'N / 95°28'W | 40°47'N / 95°25'W | 2.70 Miles | 300 Yards | 0 | 0 | 25K | 0 | Fremont |
| 12.4 | 1968-04-16 | 2 | 40°43'N / 95°27'W | 2.00 Miles | 200 Yards | 0 | 0 | 25K | 0 | Fremont | |
| 13.2 | 1959-05-26 | 2 | 40°36'N / 95°38'W | 40°49'N / 95°45'W | 15.90 Miles | 400 Yards | 0 | 0 | 25K | 0 | Fremont |
| 14.6 | 1983-05-01 | 2 | 40°38'N / 95°40'W | 40°42'N / 95°35'W | 7.00 Miles | 20 Yards | 0 | 3 | 2.5M | 0 | Fremont |
| 14.7 | 1968-04-16 | 2 | 40°40'N / 95°30'W | 0.50 Mile | 33 Yards | 0 | 0 | 3K | 0 | Fremont | |
| 14.9 | 2004-08-26 | 2 | 40°39'N / 95°36'W | 40°40'N / 95°33'W | 3.00 Miles | 880 Yards | 0 | 0 | 0 | 0 | Fremont |
| Brief Description: A tornado that eventually reached f2 in strength first touched down 2.5 miles southwest of Riverton. The tornado reached it's maximum intensity and maximum damage width of 1/2 mile when it destroyed a home on 270th street. The tornado also caused signifcant damage to another house, several vehicles, other farm outbuildings, crops and trees before lifting 1 mile southeast of Riverton. | |||||||||||
| 15.1 | 1964-06-22 | 4 | 40°42'N / 95°27'W | 40°46'N / 95°14'W | 11.90 Miles | 400 Yards | 0 | 0 | 250K | 0 | Fremont |
| 17.0 | 1964-06-19 | 3 | 40°43'N / 95°21'W | 40°50'N / 95°11'W | 11.50 Miles | 350 Yards | 0 | 2 | 2.5M | 0 | Page |
| 18.4 | 2007-05-05 | 2 | 41°03'N / 95°19'W | 41°06'N / 95°21'W | 5.00 Miles | 400 Yards | 0 | 0 | 0K | 0K | Montgomery |
| Brief Description: EVENT NARRATIVE: This tornado tore the roof off of a house, destroyed a barn, downed trees and power poles and tossed cars into a field. Most of the damage was in Montgomery county, east of Henderson (which is in Mills county). The tornado crossed into Pottawattamie county about 4 miles southeast of Macedonia. The total path length was around 11.5 miles. EPISODE NARRATIVE: A warm front that was along the Kansas and Nebraska border early Saturday morning May 5th, lifted north during the day bringing widespread heavy rain and severe weather, including tornadoes, to eastern Nebraska and southwest Iowa. The warm front was part of a large upper level system that brought several days of severe weather and flooding to the region. Heavy rain and flooding was reported with some of the activity Saturday morning, along with isolated severe thunderstorm reports. However, during the afternoon the severe weather became more widespread over northeast Nebraska where supercells spawned several tornadoes. At this time, thunderstorms, some severe with heavy rain, produced flash flooding over parts of southeast Nebraska. By evening much of the severe weather, including supercell producing tornadoes, shifted into southwest Iowa, although isolated severe thunderstorms persisted over parts of eastern Nebraska until after midnight CDT. | |||||||||||
| 19.3 | 1984-06-12 | 2 | 40°52'N / 95°56'W | 0.50 Mile | 50 Yards | 0 | 0 | 3K | 0 | Cass | |
| 19.8 | 1950-05-08 | 2 | 41°02'N / 95°16'W | 41°01'N / 95°13'W | 0 | 0 | 0K | 0 | Montgomery | ||
| 22.5 | 1975-06-18 | 2 | 40°40'N / 95°14'W | 0 | 0 | 25K | 0 | Page | |||
| 22.5 | 1964-04-12 | 4 | 40°40'N / 95°14'W | 40°50'N / 95°06'W | 13.10 Miles | 400 Yards | 1 | 28 | 2.5M | 0 | Page |
| 22.8 | 1964-09-22 | 2 | 40°39'N / 95°14'W | 40°48'N / 95°07'W | 11.80 Miles | 300 Yards | 0 | 0 | 250K | 0 | Page |
| 23.2 | 1979-08-28 | 3 | 40°41'N / 95°22'W | 40°32'N / 95°13'W | 12.80 Miles | 533 Yards | 0 | 0 | 3K | 0 | Page |
| 23.7 | 1954-04-05 | 4 | 40°35'N / 95°19'W | 40°37'N / 95°16'W | 3.30 Miles | 700 Yards | 0 | 2 | 25K | 0 | Page |
| 23.8 | 1954-04-05 | 4 | 40°33'N / 95°23'W | 40°35'N / 95°20'W | 3.00 Miles | 900 Yards | 0 | 0 | 250K | 0 | Atchison |
| 24.0 | 1955-04-23 | 2 | 40°38'N / 95°14'W | 1.50 Miles | 30 Yards | 0 | 0 | 25K | 0 | Page | |
| 24.5 | 1965-07-08 | 2 | 40°32'N / 95°42'W | 0 | 0 | 3K | 0 | Fremont | |||
| 24.7 | 1992-06-16 | 2 | 41°09'N / 95°54'W | 41°09'N / 95°50'W | 3.00 Miles | 73 Yards | 0 | 0 | 25K | 0 | Mills |
| 25.0 | 2007-05-05 | 2 | 41°09'N / 95°22'W | 41°15'N / 95°21'W | 7.00 Miles | 400 Yards | 0 | 0 | 0K | 0K | Pottawattamie |
| Brief Description: EVENT NARRATIVE: This tornado crossed into Pottawattamie county from Montgomery county about 4 miles southeast of Macedonia. The total path length was around 11.5 miles. Although over half of it was in Pottawattamie county, most of the damage was done in Montgomery county where a roof was torn off of a house, barns were destroyed and cars were tossed into a field. EPISODE NARRATIVE: A warm front that was along the Kansas and Nebraska border early Saturday morning May 5th, lifted north during the day bringing widespread heavy rain and severe weather, including tornadoes, to eastern Nebraska and southwest Iowa. The warm front was part of a large upper level system that brought several days of severe weather and flooding to the region. Heavy rain and flooding was reported with some of the activity Saturday morning, along with isolated severe thunderstorm reports. However, during the afternoon the severe weather became more widespread over northeast Nebraska where supercells spawned several tornadoes. At this time, thunderstorms, some severe with heavy rain, produced flash flooding over parts of southeast Nebraska. By evening much of the severe weather, including supercell producing tornadoes, shifted into southwest Iowa, although isolated severe thunderstorms persisted over parts of eastern Nebraska until after midnight CDT. | |||||||||||
| 25.3 | 1954-04-05 | 3 | 40°36'N / 95°14'W | 40°40'N / 95°10'W | 5.20 Miles | 667 Yards | 0 | 0 | 0K | 0 | Page |
| 25.4 | 1999-05-16 | 2 | 41°12'N / 95°35'W | 41°17'N / 95°33'W | 5.00 Miles | 120 Yards | 0 | 0 | 690K | 0 | Pottawattamie |
| Brief Description: Destroyed mostly farm buildings and equipment, did damage a few homes. | |||||||||||
| 26.2 | 1984-06-12 | 2 | 40°48'N / 96°09'W | 40°55'N / 95°59'W | 11.00 Miles | 100 Yards | 0 | 0 | 2.5M | 0 | Cass |
| 26.9 | 1964-04-12 | 2 | 40°54'N / 95°03'W | 2.00 Miles | 150 Yards | 0 | 0 | 25K | 0 | Montgomery | |
| 27.2 | 1959-05-10 | 2 | 40°56'N / 95°03'W | 1.00 Mile | 200 Yards | 0 | 0 | 3K | 0 | Montgomery | |
| 27.6 | 1968-08-18 | 3 | 41°15'N / 95°57'W | 41°15'N / 95°32'W | 21.30 Miles | 33 Yards | 0 | 0 | 2.5M | 0 | Douglas |
| 27.7 | 2004-08-26 | 2 | 40°40'N / 95°12'W | 40°39'N / 95°02'W | 7.00 Miles | 1200 Yards | 0 | 0 | 0 | 0 | Page |
| Brief Description: This tornado first touched down around 2 miles east of Coin and tracked 7 miles before lifting just northwest of Shambaugh. The tornado reached it's maximum intensity of f2 north of College Springs where a farmstead sustained serious damage. The roof of a house at this farmstead was removed and siding was damaged, a hay barn was flattened, grain bins were crushed and the roof of a silo and other nearby outbuildings were destroyed. Other farmsteads received damage to outbuildings and the crop and tree damage path at times widened to 3/4 of a mile. | |||||||||||
| 30.6 | 1984-06-07 | 3 | 40°44'N / 95°02'W | 40°50'N / 94°57'W | 7.00 Miles | 100 Yards | 0 | 3 | 2.5M | 0 | Page |
| 31.4 | 1988-07-15 | 2 | 41°16'N / 95°52'W | 2.30 Miles | 100 Yards | 0 | 42 | 25.0M | 0 | Pottawattamie | |
| 31.4 | 1988-07-15 | 3 | 41°16'N / 95°52'W | 2.80 Miles | 73 Yards | 0 | 34 | 25.0M | 0 | Pottawattamie | |
| 31.9 | 1964-06-19 | 3 | 40°44'N / 95°03'W | 40°50'N / 94°53'W | 10.60 Miles | 200 Yards | 0 | 1 | 250K | 0 | Page |
| 32.3 | 1959-05-10 | 2 | 40°31'N / 95°10'W | 0.20 Mile | 17 Yards | 0 | 0 | 25K | 0 | Nodaway | |
| 32.4 | 1955-04-23 | 2 | 40°26'N / 95°18'W | 40°28'N / 95°18'W | 2.30 Miles | 100 Yards | 0 | 0 | 25K | 0 | Atchison |
| 33.4 | 1975-05-06 | 4 | 41°10'N / 96°04'W | 41°11'N / 96°04'W | 1.10 Miles | 267 Yards | 0 | 15 | 250K | 0 | Sarpy |
| 34.5 | 1979-03-29 | 4 | 40°29'N / 95°09'W | 40°34'N / 95°02'W | 8.00 Miles | 500 Yards | 0 | 4 | 0K | 0 | Nodaway |
| 34.7 | 1999-04-08 | 2 | 40°51'N / 94°54'W | 40°54'N / 94°54'W | 3.00 Miles | 500 Yards | 0 | 0 | 500K | 0 | Taylor |
| Brief Description: As mentioned in the narrative above, an intense low pressure formed to the southwest of Iowa. The low tracked northeast and lifted into eastern Nebraska. Ahead of the low, a strong low level jet of around 60 knots continued through the day. A nearly stationary frontal boundary extended east from the low. It lifted into southeast Nebraska during the day, but made little progress into southern Iowa. Lines of thunderstorms formed along the boundary through the day and lifted north rapidly. These storms were elevated in nature and as a result produced most of their severe weather in the form of hail. As the day unfolded, a sharp dry line was clearly evident on the satellite as early as 1600 UTC across Kansas. This line raced east during the day. By afternoon, a speed max had rotated around the upper low to the southwest with wind speeds measured by the Lathrop wind profiler at 100 knots at 500 mb by mid afternoon. Jet stream winds were in excess of 120 knots at the same time. Combined with the dynamic situation mentioned above, considerable moisture convergence took place near the triple point between the warm front and the dry line. Surface dew points pooled into to the mid 60s to even a few 70 degree F. dew point readings over northwest Missouri, southeast Nebraska, and southwest Iowa. Meanwhile, dew points fell into the upper 20s over northeast Kansas and south central Nebraska behind the dry line, with teens over central and south central Kansas. Thunderstorms erupted along the dry line by mid day and advanced east through the afternoon. Low level helicity values topped out between 500 and 600 (m/s)**2 just before the first tornadoes formed. Most of the storms in the warm sector became tornadic quickly. The northern limit of the tornado tracks extended about 10 miles or so north of the warm front. Tracks became intermittent very quickly as soon as the storms crossed the surface warm front due to the layer of very cold air just north of the front. Surface temperatures on the cold side of the front were only in the upper 40s to mid 50s. The entire day was very active. Initially, warm air advection thunderstorms produced hail at many locations of central and northern Iowa. Most of is was just below severe levels however. The activity that developed during the afternoon was a combination of warm air advection and the approach of the dryline. At the beginning of the event, the main weather feature was in the form of hail. There were numerous reports of hail three quarters to one and three quarters inch in diameter. The largest hail fell in Guthrie and Dallas Counties with reports of golf ball size hail. One of the storms in the initial wave of afternoon activity became stronger as it moved into southern Story County. Initially, high winds of 60 MPH or more swept through Sheldahl area of Boone County. Greene County was also affected by high winds from the storms. A tornado dropped out of the storm as it moved into the Slater area and was on the ground for about 2 miles. Initial estimates showed 44 homes and businesses damaged in Story County, one was destroyed with major damage to another. Thirty six homes and four businesses were damaged in the town of Slater. Two people were injured during the passage of the tornado. One of the injuries involved a 70 year old man who was picked up by the tornadoes winds and thrown about 10 feet before he latched on to something. His shoulder was dislocated and he required 6 stitches due to his injuries in his hand. High winds northeast of Slater knocked several cars of a Burlington Northern freight train off the tracks after they were blown more than one quarter mile down the track. It was not possible to determine of the cars were knocked off by the tornado or high winds however. This band of storms continue to race and develop northeast through the afternoon. Damage became more sporadic, however high winds occurred as far northeast as Hardin County, with 70 MPH winds reported near New Providence. Hail reports came in from as far northeast as Grundy and Black Hawk Counties, though it was only three quarters of an inch in diameter. Attention then shifted to the tornadic storms that formed near the dry line. During the afternoon, six more tornadoes touched down in Iowa, several of which were long track tornadoes. The first touched down in Taylor County and tracked through Adams, Cass, and Adair Counties. This tornado had was an F4 intensity tornado in parts of Adair and Adams Counties. Damage was extensive with $1,000,000 damage reported in both Adams and Adair Counties. Entire farmsteads were swept clean by the tornado. At one time this tornado was a mile wide wedge with a damage path nearly two miles wide due to the circulation around the tornado. Eyewitness reports indicated that the tornado split into two distinct tornadoes at times, similar to what occurred with the intense F4 tornado in Adair County of 27 May 1995. One of the farmsteads hit near Nodaway was levelled. Reports indicated that a check was blown from the house nearly 100 miles and was found in the town of Jefferson in Greene County. Other checks and papers were found strewn along the path, stretching from Jefferson all the way back to northwest Taylor County. In Adair County, one account indicated pieces of sheet metal from one farm was lifted and deposited six miles away from the farm. Two people were injured by this tornado, one in Adams County with the other in Adair County. One of the injuries Adair County was serious as a man suffered a broken back when the tornado lifted his semi-tractortrailer truck from the Interstate and threw it into a nearby field. The other injuries from this tornado were minor enough that the people were taken to the hospital, treated, and released. There was one account of a horse being picked up by the tornado. It was lifted into the air and thrown through a stand of pine trees 40 feet high. The horse suffered serious injuries and required significant medical attention do to lacerations. The horse amazingly did survive against all odds, though was said would likely lose sight in one eye. The next tornado touched down in Union County and tracked across Madison and Dallas Counties. This tornado had an F4 strength in Union and decreased to a strong F2 in Madison Counties before intensifying again to near F3 strength as it headed into Dallas County. Damage in Union County was around $2,000,000, and around $350,000 in Madison County. There was one person injured by this tornado in Union County. In an amazing account, the Union County Sheriff reported watching as the tornado lifted the car in front of him 35 feet in the air and throwing it 250 feet. The driver was inside during this time and came out of the situation uninjured. Five coal cars were knocked off the tracks in Union County by the tornado as well. This tornado also had a double structure. From eye witness accounts, which also can be shown on Doppler radar imagery, suggest a small rope like tornado passed through the Twelve Mile Lake area shortly before the passage of the main tornado. The next tornado was a weak tornado which touched down about 4 miles west of downtown Des Moines. The tornado did little damage, but did affect one house and several trees. The tornado was seen by a local television sky camera. A short time later, an F2 tornado touched down in Warren County and tracked into southeast Polk County. The track was over rural areas and damage from it was relatively minor. A more significant F3 tornado tracked from northern Lucas County, and weakened to an F2 as it moved across Warren, part of marion, and into Jasper County. One house was destroyed in Lucas County with the four people inside sustaining minor injuries. Once again, this tornado tracked across mostly rural areas, though it did hit a business and two homes in Jasper County and did $1,000,000 in damage. One person was injured in Jasper County. The last tornado touched down in Davis County at Bloomfield and tracked northeast into Wapello County with a maximum strength of F3. Damage in Davis County was over $500,000 as 64 homes and businesses were damaged in the Bloomfield area. To the northeast, the area of the tornado track was mostly rural and damage was limited to outbuildings for the most part. One farmstead reported severe damage near Floris in Davis County. The house was nearly levelled and several outbuildings were completely destroyed. Parts of the house and outbuildings were found as far as 5 miles away from the farmstead. As the storms moved north, high winds were produced over Story County east of Story City. High winds toppled a tractor semi-trailer truck east of Story City on Interstate 35, injuring the driver. Two cars and a truck were also blown off Interstate 35 in Hamilton County. Four people were injured. Two were taken to the hospital, treated, and released. Two were listed in serious condition, one with a neck fracture, the other with a shoulder fracture. The later incident appeared to be from the rear flank downdraft behind the storm and not the initial gust front. From the preliminary data, 178 homes and business were damaged or destroyed by the tornadic storms as well as countless outbuildings. There were several reports of livestock loss as well. It is truly amazing that there was no loss of life during this event and even more amazing is the fact that the injuries that did occur were all minor. Twenty counties in Iowa experienced serious damage from the storms of the day. Iowa Governor Vilsack declared several counties in Iowa disaster areas. These included Taylor, Union, Adams, and Adair Counties. High winds accompanied the storms as the moved through Appanoose County. A local gas station recorded an 81 MPH wind gust as the storms cut a half mile wide swath of destruction west of Moravia. There were numerous reports of cattle killed by the storms. Some were killed by the tornadoes and flying debris, others by lightning. Reports in Adair County, northwest of Fontanelle indicated about 25 head of cattle were struck by lightning shortly before a tornado moved through that area. As the area of storms that produced the high winds north of Ames in central Iowa moved north, they lost their punch. A few of the storms did remain quite strong however. As the area of thunderstorms moved through Cerro Gordo County, high winds blew down a 60 foot corn crib and did some other damage on a farm near Rockwell. | |||||||||||
| 35.0 | 1979-03-29 | 4 | 40°34'N / 95°02'W | 40°42'N / 94°55'W | 10.80 Miles | 500 Yards | 0 | 16 | 2.5M | 0 | Page |
| 35.1 | 1963-04-28 | 3 | 40°23'N / 95°53'W | 40°27'N / 95°50'W | 4.90 Miles | 300 Yards | 1 | 8 | 25K | 0 | Nemaha |
| 35.1 | 1975-05-06 | 4 | 41°11'N / 96°04'W | 41°17'N / 96°01'W | 6.90 Miles | 267 Yards | 3 | 118 | 250.0M | 0 | Douglas |
| 35.2 | 1984-06-07 | 3 | 40°50'N / 94°57'W | 40°53'N / 94°50'W | 7.00 Miles | 100 Yards | 0 | 0 | 2.5M | 0 | Taylor |
| 35.3 | 1971-05-05 | 2 | 40°47'N / 94°54'W | 0 | 1 | 25K | 0 | Taylor | |||
| 35.3 | 1954-05-31 | 2 | 40°23'N / 95°25'W | 40°26'N / 95°09'W | 14.20 Miles | 440 Yards | 0 | 0 | 25K | 0 | Atchison |
| 35.7 | 1966-05-23 | 2 | 40°27'N / 95°13'W | 40°28'N / 95°06'W | 5.70 Miles | 50 Yards | 0 | 0 | 25K | 0 | Atchison |
| 36.2 | 1956-04-02 | 2 | 40°22'N / 95°50'W | 40°24'N / 95°47'W | 2.30 Miles | 100 Yards | 0 | 0 | 3K | 0 | Nemaha |
| 36.6 | 1968-04-16 | 2 | 40°23'N / 95°50'W | 1.20 Miles | 33 Yards | 0 | 0 | 25K | 0 | Nemaha | |
| 36.9 | 1975-03-27 | 2 | 41°15'N / 96°04'W | 0.50 Mile | 300 Yards | 0 | 4 | 250K | 0 | Douglas | |
| 36.9 | 2008-06-08 | 2 | 41°11'N / 96°08'W | 41°13'N / 96°07'W | 3.00 Miles | 440 Yards | 0 | 3 | 0K | 0K | Douglas |
| Brief Description: EVENT NARRATIVE: This is the continuation of tornado number 1 (of 2) to hit the Omaha metro area this night. Tornado number 1 crossed over from Sarpy county near 144th and Harrison Streets before merging with tornado number 2 just east of 132nd and Westwood Lane. From there the merged tornado continued northeast to near 114th and Shirley Streets. Tornado number 1 traveled at about 50 mph in Douglas county. Tornado number 1 produced EF2 damage in both Douglas and Sarpy counties. Although tree and roof damage was noted along most of the track, the area hardest hit in Douglas county was around 137th and Y Streets. A few homes had their roofs completely blown off in this area, while others had significant roof and siding damage. The tornado then hit a Walmart, Sams Club and Home Depot causing damage to each of those businesses after it crossed L Street. Tornado number 1 first set down just southeast of 232nd and West Angus Road about a mile west of Gretna in Sarpy county. It traveled about 8 miles in Sarpy county before crossing into Douglas county. The tornadoes spun up on the leading edge of a bow echo that gathered strength and raced through the Omaha metropolitan region. OPPD reported that 13,800 customers lost power from the storm. In total, more than 500 homeowners reported damage from the storm and according to FEMA, 7 homes were destroyed and 21 others sustained major damage. EPISODE NARRATIVE: As one unseasonably strong upper level system lifted into Canada another one dropped down behind it across the northern Plains. This caused surface low pressure to develop over northeast Kansas along a cold front that was crossing the plains. This in turn caused the front to slow down as it moved into southeast Nebraska and southwest Iowa. A small line of thunderstorms that had developed along the front moved ahead of it and encountered a strong low level jet. The combination of the low level jet, and a warm front that extended east of the low, strengthened the line segment just to the southwest of Omaha and causing it to bow out. In turn a few quick moving spin-up circulations and 2 tornadoes developed as the bow echo crossed the Omaha area. Although these tornadoes hit in the middle of the night and caused significant damage in the Omaha area, there were no deaths or serious injuries with the storm. The system also produced areas of heavy rain which caused some flash flooding and then eventual river flooding. | |||||||||||
| 37.0 | 1992-06-16 | 2 | 41°21'N / 95°21'W | 41°24'N / 95°17'W | 4.00 Miles | 100 Yards | 0 | 0 | 250K | 0 | Pottawattamie |
| 37.1 | 1974-05-13 | 3 | 41°08'N / 95°04'W | 41°13'N / 94°53'W | 10.90 Miles | 20 Yards | 0 | 0 | 250K | 0 | Montgomery |
| 37.2 | 1988-05-07 | 2 | 41°11'N / 96°10'W | 41°12'N / 96°07'W | 2.50 Miles | 73 Yards | 0 | 0 | 2.5M | 0 | Douglas |
| 37.3 | 1952-08-13 | 4 | 41°01'N / 96°19'W | 40°56'N / 96°13'W | 7.30 Miles | 33 Yards | 0 | 0 | 250K | 0 | Cass |
| 38.3 | 1982-04-15 | 2 | 40°31'N / 96°09'W | 40°32'N / 96°07'W | 2.00 Miles | 70 Yards | 0 | 0 | 250K | 0 | Otoe |
| 38.4 | 1950-05-08 | 2 | 40°23'N / 95°48'W | 40°17'N / 95°41'W | 8.80 Miles | 467 Yards | 0 | 1 | 25K | 0 | Nemaha |
| 38.5 | 2008-06-08 | 2 | 41°08'N / 96°16'W | 41°11'N / 96°08'W | 8.00 Miles | 440 Yards | 0 | 0 | 0K | 0K | Sarpy |
| Brief Description: EVENT NARRATIVE: This was the first touchdown of 2 tornadoes that hit the Omaha metro area this night. Tornado number 1 started just southeast of 232ND and West Angus Road about a mile west of Gretna. A garage was demolished at this point, suggesting EF1 damage. The tornado moved east northeast at 45 mph and produced scattered EF0 damage in Gretna with tree and shingle damage noted. From there tornado number 1 continued northeast to near 156th and Giles Road. EF 2 damage was noted just southwest of that point with major roof damage to a home. The tornado then crossed over into the Millard area of Douglas county where it continued for about 3 more miles before merging with tornado number 2. Tornado 1 also caused EF2 damage in Douglas county with much of it concentrated in the vicinity of 137th and Y Streets. The tornadoes spun up on the leading edge of a bow echo that gathered strength as it raced through the Omaha metropolitan area. More than 500 homeowners reported damage from the storm and OPPD reported that 13,800 customers lost power. EPISODE NARRATIVE: As one unseasonably strong upper level system lifted into Canada another one dropped down behind it across the northern Plains. This caused surface low pressure to develop over northeast Kansas along a cold front that was crossing the plains. This in turn caused the front to slow down as it moved into southeast Nebraska and southwest Iowa. A small line of thunderstorms that had developed along the front moved ahead of it and encountered a strong low level jet. The combination of the low level jet, and a warm front that extended east of the low, strengthened the line segment just to the southwest of Omaha and causing it to bow out. In turn a few quick moving spin-up circulations and 2 tornadoes developed as the bow echo crossed the Omaha area. Although these tornadoes hit in the middle of the night and caused significant damage in the Omaha area, there were no deaths or serious injuries with the storm. The system also produced areas of heavy rain which caused some flash flooding and then eventual river flooding. | |||||||||||
| 39.0 | 1999-04-08 | 4 | 40°53'N / 94°53'W | 41°09'N / 94°48'W | 18.00 Miles | 1000 Yards | 0 | 1 | 1.0M | 0 | Adams |
| Brief Description: As mentioned in the narrative above, an intense low pressure formed to the southwest of Iowa. The low tracked northeast and lifted into eastern Nebraska. Ahead of the low, a strong low level jet of around 60 knots continued through the day. A nearly stationary frontal boundary extended east from the low. It lifted into southeast Nebraska during the day, but made little progress into southern Iowa. Lines of thunderstorms formed along the boundary through the day and lifted north rapidly. These storms were elevated in nature and as a result produced most of their severe weather in the form of hail. As the day unfolded, a sharp dry line was clearly evident on the satellite as early as 1600 UTC across Kansas. This line raced east during the day. By afternoon, a speed max had rotated around the upper low to the southwest with wind speeds measured by the Lathrop wind profiler at 100 knots at 500 mb by mid afternoon. Jet stream winds were in excess of 120 knots at the same time. Combined with the dynamic situation mentioned above, considerable moisture convergence took place near the triple point between the warm front and the dry line. Surface dew points pooled into to the mid 60s to even a few 70 degree F. dew point readings over northwest Missouri, southeast Nebraska, and southwest Iowa. Meanwhile, dew points fell into the upper 20s over northeast Kansas and south central Nebraska behind the dry line, with teens over central and south central Kansas. Thunderstorms erupted along the dry line by mid day and advanced east through the afternoon. Low level helicity values topped out between 500 and 600 (m/s)**2 just before the first tornadoes formed. Most of the storms in the warm sector became tornadic quickly. The northern limit of the tornado tracks extended about 10 miles or so north of the warm front. Tracks became intermittent very quickly as soon as the storms crossed the surface warm front due to the layer of very cold air just north of the front. Surface temperatures on the cold side of the front were only in the upper 40s to mid 50s. The entire day was very active. Initially, warm air advection thunderstorms produced hail at many locations of central and northern Iowa. Most of is was just below severe levels however. The activity that developed during the afternoon was a combination of warm air advection and the approach of the dryline. At the beginning of the event, the main weather feature was in the form of hail. There were numerous reports of hail three quarters to one and three quarters inch in diameter. The largest hail fell in Guthrie and Dallas Counties with reports of golf ball size hail. One of the storms in the initial wave of afternoon activity became stronger as it moved into southern Story County. Initially, high winds of 60 MPH or more swept through Sheldahl area of Boone County. Greene County was also affected by high winds from the storms. A tornado dropped out of the storm as it moved into the Slater area and was on the ground for about 2 miles. Initial estimates showed 44 homes and businesses damaged in Story County, one was destroyed with major damage to another. Thirty six homes and four businesses were damaged in the town of Slater. Two people were injured during the passage of the tornado. One of the injuries involved a 70 year old man who was picked up by the tornadoes winds and thrown about 10 feet before he latched on to something. His shoulder was dislocated and he required 6 stitches due to his injuries in his hand. High winds northeast of Slater knocked several cars of a Burlington Northern freight train off the tracks after they were blown more than one quarter mile down the track. It was not possible to determine of the cars were knocked off by the tornado or high winds however. This band of storms continue to race and develop northeast through the afternoon. Damage became more sporadic, however high winds occurred as far northeast as Hardin County, with 70 MPH winds reported near New Providence. Hail reports came in from as far northeast as Grundy and Black Hawk Counties, though it was only three quarters of an inch in diameter. Attention then shifted to the tornadic storms that formed near the dry line. During the afternoon, six more tornadoes touched down in Iowa, several of which were long track tornadoes. The first touched down in Taylor County and tracked through Adams, Cass, and Adair Counties. This tornado had was an F4 intensity tornado in parts of Adair and Adams Counties. Damage was extensive with $1,000,000 damage reported in both Adams and Adair Counties. Entire farmsteads were swept clean by the tornado. At one time this tornado was a mile wide wedge with a damage path nearly two miles wide due to the circulation around the tornado. Eyewitness reports indicated that the tornado split into two distinct tornadoes at times, similar to what occurred with the intense F4 tornado in Adair County of 27 May 1995. One of the farmsteads hit near Nodaway was levelled. Reports indicated that a check was blown from the house nearly 100 miles and was found in the town of Jefferson in Greene County. Other checks and papers were found strewn along the path, stretching from Jefferson all the way back to northwest Taylor County. In Adair County, one account indicated pieces of sheet metal from one farm was lifted and deposited six miles away from the farm. Two people were injured by this tornado, one in Adams County with the other in Adair County. One of the injuries Adair County was serious as a man suffered a broken back when the tornado lifted his semi-tractortrailer truck from the Interstate and threw it into a nearby field. The other injuries from this tornado were minor enough that the people were taken to the hospital, treated, and released. There was one account of a horse being picked up by the tornado. It was lifted into the air and thrown through a stand of pine trees 40 feet high. The horse suffered serious injuries and required significant medical attention do to lacerations. The horse amazingly did survive against all odds, though was said would likely lose sight in one eye. The next tornado touched down in Union County and tracked across Madison and Dallas Counties. This tornado had an F4 strength in Union and decreased to a strong F2 in Madison Counties before intensifying again to near F3 strength as it headed into Dallas County. Damage in Union County was around $2,000,000, and around $350,000 in Madison County. There was one person injured by this tornado in Union County. In an amazing account, the Union County Sheriff reported watching as the tornado lifted the car in front of him 35 feet in the air and throwing it 250 feet. The driver was inside during this time and came out of the situation uninjured. Five coal cars were knocked off the tracks in Union County by the tornado as well. This tornado also had a double structure. From eye witness accounts, which also can be shown on Doppler radar imagery, suggest a small rope like tornado passed through the Twelve Mile Lake area shortly before the passage of the main tornado. The next tornado was a weak tornado which touched down about 4 miles west of downtown Des Moines. The tornado did little damage, but did affect one house and several trees. The tornado was seen by a local television sky camera. A short time later, an F2 tornado touched down in Warren County and tracked into southeast Polk County. The track was over rural areas and damage from it was relatively minor. A more significant F3 tornado tracked from northern Lucas County, and weakened to an F2 as it moved across Warren, part of marion, and into Jasper County. One house was destroyed in Lucas County with the four people inside sustaining minor injuries. Once again, this tornado tracked across mostly rural areas, though it did hit a business and two homes in Jasper County and did $1,000,000 in damage. One person was injured in Jasper County. The last tornado touched down in Davis County at Bloomfield and tracked northeast into Wapello County with a maximum strength of F3. Damage in Davis County was over $500,000 as 64 homes and businesses were damaged in the Bloomfield area. To the northeast, the area of the tornado track was mostly rural and damage was limited to outbuildings for the most part. One farmstead reported severe damage near Floris in Davis County. The house was nearly levelled and several outbuildings were completely destroyed. Parts of the house and outbuildings were found as far as 5 miles away from the farmstead. As the storms moved north, high winds were produced over Story County east of Story City. High winds toppled a tractor semi-trailer truck east of Story City on Interstate 35, injuring the driver. Two cars and a truck were also blown off Interstate 35 in Hamilton County. Four people were injured. Two were taken to the hospital, treated, and released. Two were listed in serious condition, one with a neck fracture, the other with a shoulder fracture. The later incident appeared to be from the rear flank downdraft behind the storm and not the initial gust front. From the preliminary data, 178 homes and business were damaged or destroyed by the tornadic storms as well as countless outbuildings. There were several reports of livestock loss as well. It is truly amazing that there was no loss of life during this event and even more amazing is the fact that the injuries that did occur were all minor. Twenty counties in Iowa experienced serious damage from the storms of the day. Iowa Governor Vilsack declared several counties in Iowa disaster areas. These included Taylor, Union, Adams, and Adair Counties. High winds accompanied the storms as the moved through Appanoose County. A local gas station recorded an 81 MPH wind gust as the storms cut a half mile wide swath of destruction west of Moravia. There were numerous reports of cattle killed by the storms. Some were killed by the tornadoes and flying debris, others by lightning. Reports in Adair County, northwest of Fontanelle indicated about 25 head of cattle were struck by lightning shortly before a tornado moved through that area. As the area of storms that produced the high winds north of Ames in central Iowa moved north, they lost their punch. A few of the storms did remain quite strong however. As the area of thunderstorms moved through Cerro Gordo County, high winds blew down a 60 foot corn crib and did some other damage on a farm near Rockwell. | |||||||||||
| 39.0 | 1954-05-31 | 2 | 40°26'N / 95°09'W | 40°27'N / 95°01'W | 6.80 Miles | 440 Yards | 0 | 0 | 25K | 0 | Morgan |
| 39.4 | 1988-05-07 | 2 | 41°20'N / 95°57'W | 41°27'N / 95°49'W | 7.20 Miles | 73 Yards | 0 | 0 | 2.5M | 0 | Pottawattamie |
| 39.5 | 2007-05-06 | 2 | 41°10'N / 94°58'W | 41°15'N / 94°56'W | 7.00 Miles | 830 Yards | 0 | 0 | 1.0M | 0K | Cass |
| Brief Description: EVENT NARRATIVE: Tornado touched down on the southern Cass County line and moved northeast. The last 2 miles of the track showed an intermittent nature. Average path width was 100 to 200 yards wide with a maximum width of about one half mile. Estimated wind speed was 120 to 130 MPH. EPISODE NARRATIVE: A very strong upper level low pressure trough had carved out over the western U.S. Iowa was in the strong southwest flow on the front side of this system. A surface warm front lifted north into southwest Iowa during the evening of the 5th. The airmass became quite unstable with plenty of deep moisture advection into the areas. Precipitable water values were in the 1.5 to 1.75 inch range by midnight. The lifted index fell to the -6 to -8 C. There was a reasonable amount of CAPE available with about 2500 J/kg at the onset of the event. The LCL was around 1000 meters and the freezing level was a relatively high 13,500 feet. With the warm front in the vicinity, there was a considerable amount of helicity present with values in the 300 to 550 range. During the evening of the 5th, most of the significant convection remained to the west of the DMX CWA. After midnight, the low level jet increased to 50 to 70 kts and began to veer. This helped push the convection east during the overnight hours. Strong cells developed in southwest Iowa near the warm frontal boundary. Two tornadoes occurred with this initial set of convection. An EF2 tornado touched down in Cass County. The tornado first developed right on the southern Cass County line, from highway 71 to three quarters of a mile west. Four farmsteads were damaged along county road G66 within the mile west of highway 71, producing damage up to EF1. The tornado narrowed slightly and intensified in the next mile, downing two sets of metal electrical transmission poles. The most severe damage occurred at a farm service and grain elevator business on highway 71. This was 2 miles into Cass County or 3 miles south of the town of Lyman. EF2 damage occurred at this site with winds estimated at 120-130 mph. The average path width was 100 to 200 yards, with a maximum width of about one half mile. Empty semi trailers were flipped, two tall grain bins were flattened. A large metal clad truck service building was flattened on the south end and much of the roof was off the north end. The west part of the roof of an office building was torn off and the wall collapsed. The house at the north end of the site had windows blown out and part of the roof damaged. The tornado continued north along and just east of highway 71 for another two miles causing some damage to homes with some outbuildings unroofed or destroyed. The last apparent damage along the tornado path occurred two miles northeast of Lyman where power poles were snapped. Several areas between Cumberland and Anita were also surveyed. Damage along this path was consistent with straight line winds of 70 to 90 mph. Damage included downed trees and sheet metal torn off sheds and outbuildings. A storage building in Anita was significantly damaged. A total of 115 to 120 homes were damaged in Cass County by the storm. As the night progressed, a bow echo advanced into the state from the southwest. There were several reports of high winds and hail with this line. One of the storm in the line produced a small EF0 tornado in Union County. Some damage occurred at several farmsteads along the path. This same cell produced very large hail with hail up to baseball size reported in the Afton area. The hail was wind driven, damaging skylights, windows, and cars. Hail stones were driven through car windshields and also through windows in houses. Some damage even occurred inside of two homes as the hail stones continued inside of the house. This was the most significant hail from the storms. The hail reportedly piled up several inches deep and lasted for at least 4 hours after the storm. In the survey conducted by the Emergency Manager it was found that in Afton, 236 primary buildings and 174 out buildings and garages had moderate hail damage consisting of roof damage...primarily to the slopes facing south and west. All roof vents and eves, either aluminum or plastic, were damaged. Almost 100 percent of the buildings with south-facing windows had damage to screens, broken glass storm windows, interior single and double pane windows, and in cases of plastic framed windows even the sashes and stools were damaged. All siding was damaged on those sides no matter of the material. In the rural areas around Afton, 30 of the 38 residences received moderate damage. In Arispe, 5 miles south of Afton, hail damage occurred, but was not as severe with 40 residences reporting minor damage and 30 out buildings being damaged. All together, 346 vehicles were hail damaged and many had Windows broken completely out. Twenty three campers suffered vent and sky lite damages as well as exterior damages. Hardly any of the skylights withstood the hail, either in campers or houses. Though many of the storms produced hail, much of it was under one half inch in diameter. Another brief tornado touched town in Guthrie County south of Bayard. The tornado caused EF1 damage. A roof was blown off of a building there, and blown westward. Wind was the primary threat with the storms. There were several reports of trees downed by the high winds, barns, and outbuildings being blown over or destroyed. A semi-tractortrailer was blown off of Interstate 80 west of Adair. The event turned into a significant event both in areal coverage, as well as for its variety of weather features. Flooding became a significant problem later in the event with several reports of 3 to 5 inch rainfall received. Flash flooding occurred over parts of southwest into west central Iowa. Cass, Audubon, and Carroll Counties were the hardest hit. Areal flood warnings were issued for these counties. Widespread flooding too place, with Cass County hard hit. The Governor of Iowa, Chet Culver, declared a state disaster for several counties across southwest and south central Iowa due to the flash flooding. This included Decatur County in the Des Moines CWA. Toward dawn, high winds became a problem over parts of northwest Iowa. The winds affected a 6 county area with wind gusts in the 50 to 65 MPH range for several hours. | |||||||||||
| 40.4 | 1957-05-09 | 2 | 40°32'N / 96°18'W | 40°39'N / 96°11'W | 9.90 Miles | 120 Yards | 0 | 0 | 25K | 0 | Otoe |
| 40.5 | 1988-05-07 | 2 | 41°07'N / 96°20'W | 41°11'N / 96°10'W | 6.70 Miles | 73 Yards | 2 | 1 | 2.5M | 0 | Sarpy |
| 40.6 | 1965-07-01 | 3 | 40°43'N / 96°25'W | 40°39'N / 96°11'W | 12.80 Miles | 33 Yards | 0 | 1 | 250K | 0 | Otoe |
| 40.7 | 1982-04-15 | 2 | 40°30'N / 96°12'W | 40°31'N / 96°09'W | 3.00 Miles | 70 Yards | 0 | 0 | 250K | 0 | Johnson |
| 40.9 | 1981-04-11 | 2 | 40°41'N / 94°45'W | 40°43'N / 94°53'W | 6.90 Miles | 50 Yards | 0 | 2 | 2.5M | 0 | Taylor |
| 41.0 | 1976-06-26 | 4 | 41°27'N / 95°36'W | 41°29'N / 95°30'W | 5.10 Miles | 200 Yards | 0 | 6 | 2.5M | 0 | Pottawattamie |
| 41.0 | 1984-06-07 | 3 | 40°53'N / 94°50'W | 40°59'N / 94°44'W | 11.00 Miles | 100 Yards | 0 | 0 | 2.5M | 0 | Adams |
| 41.6 | 1967-06-09 | 2 | 40°35'N / 96°23'W | 40°39'N / 96°11'W | 11.30 Miles | 33 Yards | 0 | 0 | 25K | 0 | Otoe |
| 42.1 | 1991-04-26 | 3 | 40°36'N / 96°24'W | 40°47'N / 96°16'W | 14.00 Miles | 350 Yards | 0 | 2 | 2.5M | 0 | Otoe |
| 42.2 | 1975-05-06 | 2 | 41°24'N / 95°51'W | 41°32'N / 95°40'W | 12.80 Miles | 500 Yards | 0 | 0 | 25K | 0 | Pottawattamie |
| 43.1 | 1979-03-29 | 3 | 40°35'N / 94°57'W | 40°54'N / 94°34'W | 29.60 Miles | 500 Yards | 0 | 1 | 2.5M | 0 | Taylor |
| 43.1 | 1963-04-18 | 2 | 41°10'N / 94°50'W | 0 | 0 | 25K | 0 | Cass | |||
| 43.2 | 1954-04-05 | 2 | 40°40'N / 94°53'W | 40°43'N / 94°40'W | 11.50 Miles | 333 Yards | 0 | 0 | 0K | 0 | Taylor |
| 44.0 | 1959-05-18 | 2 | 40°59'N / 94°44'W | 1.00 Mile | 200 Yards | 0 | 0 | 250K | 0 | Adams | |
| 44.0 | 1952-11-16 | 3 | 40°27'N / 95°04'W | 40°34'N / 94°41'W | 21.60 Miles | 600 Yards | 0 | 2 | 25K | 0 | Nodaway |
| 44.7 | 1970-05-12 | 2 | 41°28'N / 95°14'W | 41°26'N / 95°07'W | 5.90 Miles | 400 Yards | 0 | 0 | 250K | 0 | Pottawattamie |
| 45.5 | 1984-06-07 | 2 | 41°10'N / 95°04'W | 41°27'N / 94°45'W | 23.00 Miles | 150 Yards | 0 | 8 | 2.5M | 0 | Cass |
| 45.7 | 1965-05-25 | 2 | 41°24'N / 95°02'W | 0 | 0 | 25K | 0 | Cass | |||
| 46.5 | 1972-09-12 | 2 | 41°30'N / 95°42'W | 41°35'N / 95°39'W | 5.90 Miles | 100 Yards | 0 | 0 | 25K | 0 | Harrison |
| 46.7 | 1988-05-07 | 2 | 41°07'N / 96°28'W | 41°07'N / 96°20'W | 7.00 Miles | 73 Yards | 0 | 0 | 2.5M | 0 | Saunders |
| 47.3 | 1964-04-20 | 3 | 41°24'N / 95°03'W | 41°24'N / 94°55'W | 6.10 Miles | 350 Yards | 0 | 1 | 25K | 0 | Cass |
| 47.5 | 1964-08-27 | 2 | 41°26'N / 95°02'W | 1.00 Mile | 50 Yards | 0 | 0 | 25K | 0 | Cass | |
| 47.8 | 1957-04-25 | 4 | 40°49'N / 96°54'W | 41°11'N / 96°02'W | 51.70 Miles | 333 Yards | 0 | 0 | 2.5M | 0 | Lancaster |
| 47.9 | 1956-05-29 | 2 | 41°21'N / 94°57'W | 41°23'N / 94°53'W | 3.30 Miles | 50 Yards | 0 | 0 | 0K | 0 | Cass |
| 48.0 | 1976-06-13 | 2 | 41°25'N / 95°08'W | 41°30'N / 95°00'W | 8.50 Miles | 100 Yards | 0 | 0 | 25K | 0 | Cass |
| 48.2 | 1975-05-06 | 2 | 41°28'N / 95°52'W | 41°37'N / 95°48'W | 10.60 Miles | 33 Yards | 0 | 0 | 25K | 0 | Pottawattamie |
| 48.2 | 1973-09-25 | 2 | 41°33'N / 95°20'W | 0 | 0 | 25K | 0 | Shelby | |||
| 48.4 | 1999-04-08 | 3 | 41°09'N / 94°47'W | 41°15'N / 94°42'W | 7.50 Miles | 1000 Yards | 0 | 0 | 186K | 0 | Cass |
| Brief Description: As mentioned in the narrative above, an intense low pressure formed to the southwest of Iowa. The low tracked northeast and lifted into eastern Nebraska. Ahead of the low, a strong low level jet of around 60 knots continued through the day. A nearly stationary frontal boundary extended east from the low. It lifted into southeast Nebraska during the day, but made little progress into southern Iowa. Lines of thunderstorms formed along the boundary through the day and lifted north rapidly. These storms were elevated in nature and as a result produced most of their severe weather in the form of hail. As the day unfolded, a sharp dry line was clearly evident on the satellite as early as 1600 UTC across Kansas. This line raced east during the day. By afternoon, a speed max had rotated around the upper low to the southwest with wind speeds measured by the Lathrop wind profiler at 100 knots at 500 mb by mid afternoon. Jet stream winds were in excess of 120 knots at the same time. Combined with the dynamic situation mentioned above, considerable moisture convergence took place near the triple point between the warm front and the dry line. Surface dew points pooled into to the mid 60s to even a few 70 degree F. dew point readings over northwest Missouri, southeast Nebraska, and southwest Iowa. Meanwhile, dew points fell into the upper 20s over northeast Kansas and south central Nebraska behind the dry line, with teens over central and south central Kansas. Thunderstorms erupted along the dry line by mid day and advanced east through the afternoon. Low level helicity values topped out between 500 and 600 (m/s)**2 just before the first tornadoes formed. Most of the storms in the warm sector became tornadic quickly. The northern limit of the tornado tracks extended about 10 miles or so north of the warm front. Tracks became intermittent very quickly as soon as the storms crossed the surface warm front due to the layer of very cold air just north of the front. Surface temperatures on the cold side of the front were only in the upper 40s to mid 50s. The entire day was very active. Initially, warm air advection thunderstorms produced hail at many locations of central and northern Iowa. Most of is was just below severe levels however. The activity that developed during the afternoon was a combination of warm air advection and the approach of the dryline. At the beginning of the event, the main weather feature was in the form of hail. There were numerous reports of hail three quarters to one and three quarters inch in diameter. The largest hail fell in Guthrie and Dallas Counties with reports of golf ball size hail. One of the storms in the initial wave of afternoon activity became stronger as it moved into southern Story County. Initially, high winds of 60 MPH or more swept through Sheldahl area of Boone County. Greene County was also affected by high winds from the storms. A tornado dropped out of the storm as it moved into the Slater area and was on the ground for about 2 miles. Initial estimates showed 44 homes and businesses damaged in Story County, one was destroyed with major damage to another. Thirty six homes and four businesses were damaged in the town of Slater. Two people were injured during the passage of the tornado. One of the injuries involved a 70 year old man who was picked up by the tornadoes winds and thrown about 10 feet before he latched on to something. His shoulder was dislocated and he required 6 stitches due to his injuries in his hand. High winds northeast of Slater knocked several cars of a Burlington Northern freight train off the tracks after they were blown more than one quarter mile down the track. It was not possible to determine of the cars were knocked off by the tornado or high winds however. This band of storms continue to race and develop northeast through the afternoon. Damage became more sporadic, however high winds occurred as far northeast as Hardin County, with 70 MPH winds reported near New Providence. Hail reports came in from as far northeast as Grundy and Black Hawk Counties, though it was only three quarters of an inch in diameter. Attention then shifted to the tornadic storms that formed near the dry line. During the afternoon, six more tornadoes touched down in Iowa, several of which were long track tornadoes. The first touched down in Taylor County and tracked through Adams, Cass, and Adair Counties. This tornado had was an F4 intensity tornado in parts of Adair and Adams Counties. Damage was extensive with $1,000,000 damage reported in both Adams and Adair Counties. Entire farmsteads were swept clean by the tornado. At one time this tornado was a mile wide wedge with a damage path nearly two miles wide due to the circulation around the tornado. Eyewitness reports indicated that the tornado split into two distinct tornadoes at times, similar to what occurred with the intense F4 tornado in Adair County of 27 May 1995. One of the farmsteads hit near Nodaway was levelled. Reports indicated that a check was blown from the house nearly 100 miles and was found in the town of Jefferson in Greene County. Other checks and papers were found strewn along the path, stretching from Jefferson all the way back to northwest Taylor County. In Adair County, one account indicated pieces of sheet metal from one farm was lifted and deposited six miles away from the farm. Two people were injured by this tornado, one in Adams County with the other in Adair County. One of the injuries Adair County was serious as a man suffered a broken back when the tornado lifted his semi-tractortrailer truck from the Interstate and threw it into a nearby field. The other injuries from this tornado were minor enough that the people were taken to the hospital, treated, and released. There was one account of a horse being picked up by the tornado. It was lifted into the air and thrown through a stand of pine trees 40 feet high. The horse suffered serious injuries and required significant medical attention do to lacerations. The horse amazingly did survive against all odds, though was said would likely lose sight in one eye. The next tornado touched down in Union County and tracked across Madison and Dallas Counties. This tornado had an F4 strength in Union and decreased to a strong F2 in Madison Counties before intensifying again to near F3 strength as it headed into Dallas County. Damage in Union County was around $2,000,000, and around $350,000 in Madison County. There was one person injured by this tornado in Union County. In an amazing account, the Union County Sheriff reported watching as the tornado lifted the car in front of him 35 feet in the air and throwing it 250 feet. The driver was inside during this time and came out of the situation uninjured. Five coal cars were knocked off the tracks in Union County by the tornado as well. This tornado also had a double structure. From eye witness accounts, which also can be shown on Doppler radar imagery, suggest a small rope like tornado passed through the Twelve Mile Lake area shortly before the passage of the main tornado. The next tornado was a weak tornado which touched down about 4 miles west of downtown Des Moines. The tornado did little damage, but did affect one house and several trees. The tornado was seen by a local television sky camera. A short time later, an F2 tornado touched down in Warren County and tracked into southeast Polk County. The track was over rural areas and damage from it was relatively minor. A more significant F3 tornado tracked from northern Lucas County, and weakened to an F2 as it moved across Warren, part of marion, and into Jasper County. One house was destroyed in Lucas County with the four people inside sustaining minor injuries. Once again, this tornado tracked across mostly rural areas, though it did hit a business and two homes in Jasper County and did $1,000,000 in damage. One person was injured in Jasper County. The last tornado touched down in Davis County at Bloomfield and tracked northeast into Wapello County with a maximum strength of F3. Damage in Davis County was over $500,000 as 64 homes and businesses were damaged in the Bloomfield area. To the northeast, the area of the tornado track was mostly rural and damage was limited to outbuildings for the most part. One farmstead reported severe damage near Floris in Davis County. The house was nearly levelled and several outbuildings were completely destroyed. Parts of the house and outbuildings were found as far as 5 miles away from the farmstead. As the storms moved north, high winds were produced over Story County east of Story City. High winds toppled a tractor semi-trailer truck east of Story City on Interstate 35, injuring the driver. Two cars and a truck were also blown off Interstate 35 in Hamilton County. Four people were injured. Two were taken to the hospital, treated, and released. Two were listed in serious condition, one with a neck fracture, the other with a shoulder fracture. The later incident appeared to be from the rear flank downdraft behind the storm and not the initial gust front. From the preliminary data, 178 homes and business were damaged or destroyed by the tornadic storms as well as countless outbuildings. There were several reports of livestock loss as well. It is truly amazing that there was no loss of life during this event and even more amazing is the fact that the injuries that did occur were all minor. Twenty counties in Iowa experienced serious damage from the storms of the day. Iowa Governor Vilsack declared several counties in Iowa disaster areas. These included Taylor, Union, Adams, and Adair Counties. High winds accompanied the storms as the moved through Appanoose County. A local gas station recorded an 81 MPH wind gust as the storms cut a half mile wide swath of destruction west of Moravia. There were numerous reports of cattle killed by the storms. Some were killed by the tornadoes and flying debris, others by lightning. Reports in Adair County, northwest of Fontanelle indicated about 25 head of cattle were struck by lightning shortly before a tornado moved through that area. As the area of storms that produced the high winds north of Ames in central Iowa moved north, they lost their punch. A few of the storms did remain quite strong however. As the area of thunderstorms moved through Cerro Gordo County, high winds blew down a 60 foot corn crib and did some other damage on a farm near Rockwell. | |||||||||||
| 49.1 | 1952-08-13 | 4 | 41°13'N / 96°35'W | 41°01'N / 96°19'W | 19.40 Miles | 110 Yards | 0 | 20 | 250K | 0 | Saunders |
| 49.5 | 1995-05-08 | 2 | 40°27'N / 96°23'W | 40°31'N / 96°20'W | 1.50 Miles | 400 Yards | 0 | 0 | 450K | 0 | Nemaha |
| Brief Description: A tornado touched down four miles west and one-half mile south of Auburn and did extensive damage to a house, farm, its outbuildings, and power lines along the path of the tornado. A second farmsite was damage three and one-half miles west of Auburn. | |||||||||||
* The information on this page is based on the global volcano database, the U.S. earthquake database of 1638-1985, and the U.S. Tornado and Weather Extremes database of 1950-2010.