Tornadoes and Flash Flood in Iowa, April 8 to 9, 2001

Name: Tornadoes and Flash Flood in Iowa, April 8 to 9, 2001
Start: 2001-04-08T18:01
End: 2001-04-09T02:00
Location: Iowa

April 8 to 9, 2001 · NWS DMX · 39 events in 15 counties and zones

Where it happened

Every event with a place to put it; 4 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 7
Property damage: $518,000
Crop damage: None recorded
Events: 39

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS DMX wrote it up.

Following the passage of the powerful storm system earlier in the weekend, another round of severe weather was on tap for the state. The cold front from the previous storm did not move all that far to the south of Iowa. As a result, warm and moist air was able to move north into Iowa rapidly. A warm front lifted into southern Iowa during the late afternoon hours, sending temperatures into the 80s over parts of southern Iowa. Dew point temperatures jumped into the low to mid 60s. The atmosphere became very unstable with thunderstorms developing along the front. Most of the storms were associated with the warm front itself, though a mesoscale feature moved along the front setting the stage for an additional like of thunderstorms that developed north to south in south central Iowa. The main feature with the storms was hail. There were numerous reports of hail ranging from nickel size up to golf ball size. Several of the storms had well developed meso circulations associated with them. A few tornadoes resulted. Two of the tornadoes were very small and only touched down briefly in Tama and Dallas Counties. The other tornadoes were stronger. One tornado touched down in Decatur County near Leon. Two people were injured, one requiring hospitalization, as a mobile home was overturned by the gust front ahead of the storm itself. The second of the stronger tornadoes moved through Adams County. A trailer house was overturned and the roofs were removed from two sheds on a farm northeast of Mt. Etna. Thunderstorms produced very heavy rainfall of one to two inches per hour over Ringgold County. Total rainfall approached 4 inches in less than 3 hours as storms repeatedly moved across the same areas. The rain caused flash flooding in the county. In one instance, Lotts Creek overtopped a road southeast of Mt. Ayr, causing nearly $50,000 in damage as the road washed out. As the storms moved through Decatur County, lightning stuck a house in Garde Grove. The house was set on fire, but it was not detected for several hours after the lightning strike. The house was destroyed and completely burned to the ground.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Des Moines, IA wrote its last area forecast discussion before the first event at Apr 8, 5:16 PM CST, 45 minutes earlier.

Area forecast discussion, Apr 8, 5:16 PM CST, 45 minutes before

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE DES MOINES IA
615 PM CST SUN APR 8 2001

A QUICK MESOSCALE UPDATE.  SHALLOW MOISTURE IS DELAYING DEEP
CONVECTIVE DEVELOPMENT TO THIS POINT.  CELLS ARE VERY PULSY SO FAR.
GOOD MOISTURE CONVERGENCE ALONG THE NOW STATIONARY FRONT AS SEEN BY
NEARLY STATIONARY FINE LINE ON 88D.  AUGUSTINE/CARACENA METHOD WOULD
POINT TO FAVORED MCS INITIATION IN NE KS INTO SW IA, WHICH WOULD
MAKE SENSE GIVEN STRONGER MOISTURE FLUX IN THIS AREA.  18Z META
HANDLING THIS WELL, AND AGREE WITH LATEST QPF DISC.  TORNADO THREAT
WOULD APPEAR VERY LOW GIVEN VERY HIGH LFC HEIGHTS AROUND 8KFT EARLY
THIS EVENING BASED ON MODIFIED 18Z TOP SOUNDING.  MORE LOW LEVEL
MOISTURE WOULD INCREASE THIS THREAT LATER, BUT BELIEVE WE WILL BE IN
A MORE MCS MODE BY THAT TIME.  SO LARGE HAIL AND SOME DRY
MICROBURSTS ARE THE MAIN THREATS.  WILL CONTINUE TO MONITOR
SITUATION.

.DSM...NONE

KULA

In the hours before

Special weather statement, Apr 8, 1:32 PM CST, 4 hours 29 minutes before

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
232 PM CDT SUN APR 8 2001

A STRONG WARM FRONT HAS PUSHED INTO SOUTHERN IOWA AND IS EXPECTED TO
GO STATIONARY ALONG THE INTERSTATE 80 CORRIDOR THIS EVENING. A FEW
THUNDERSTORMS...DEVELOPING IN AN AREA OF MODERATE INSTABILITY AND
HIGH WIND SHEAR...MAY BECOME SEVERE THIS EVENING. RELATIVELY HIGH
LOW LEVEL MOISTURE...COMBINED WITH SLOW MOVING STORMS...WILL LIKELY
PRODUCE LOCALIZED HEAVY RAINFALL IN SOUTHERN PORTIONS OF THE STATE.

SEE SITE SPECIFIC DETAILS BELOW FOR MORE INFORMATION.

IAZ037>039-047>050-057>061-070>073-081-082-092-090000-
ADAIR-ADAMS-AUDUBON-BLACK HAWK-BOONE-CASS-DALLAS-GRUNDY-GUTHRIE-
HARDIN-JASPER-MADISON-MARSHALL-POLK-STORY-TAMA-TAYLOR-UNION-WARREN-
INCLUDING THE CITIES OF...AMES...ATLANTIC...BOONE...CRESTON...
DES MOINES...INDIANOLA...IOWA FALLS...MARSHALLTOWN...NEWTON...
WATERLOO/CEDAR FALLS
232 PM CDT SUN APR 8 2001

* EVENT TIMING... 8 PM THROUGH 3 AM

* THREAT CATEGORIES...
     TORNADO......... NONE
     DAMAGING WINDS.. LOW
     LARGE HAIL...... LOW
     FLASH FLOODING.. LOW

* SPOTTER ACTIVATION OUTLOOK... LOW

IAZ062-074-075-083>086-093>097-090000-
APPANOOSE-CLARKE-DAVIS-DECATUR-LUCAS-MAHASKA-MARION-MONROE-POWESHIEK-
RINGGOLD-WAPELLO-WAYNE-
INCLUDING THE CITIES OF...CENTERVILLE...CHARITON...GRINNELL...
KNOXVILLE...LAMONI...MOUNT AYR...OSKALOOSA...OTTUMWA
232 PM CDT SUN APR 8 2001

* EVENT TIMING... 8 PM THROUGH 3 AM

* THREAT CATEGORIES...
     TORNADO......... LOW
     DAMAGING WINDS.. LOW
     LARGE HAIL...... MODERATE
     FLASH FLOODING.. MODERATE

* SPOTTER ACTIVATION OUTLOOK... MODERATE

* RAINFALL AMOUNTS MAY REACH 1 TO 3 INCHES BY EARLY MONDAY MORNING...
POSSIBLY FALLING IN LESS THAN 3 HOURS.

-------------------------------------------------------------------

THREAT KEY:
    TORNADO......... ANY TORNADO OCCURRENCE
    DAMAGING WINDS.. WINDS >= 58 MPH
    LARGE HAIL...... HAIL >= 3/4 INCH DIAMETER
    FLASH FLOODING.. FLOODING CAUSED BY HEAVY RAINS WITHIN 6 HOURS.
                     POSES THREAT TO LIFE OR PROPERTY.

THREAT CATEGORY KEY:  PROBABILITY OF THREAT OCCURRING WITHIN 25
                      MILES OF POINT WITHIN FORECAST AREA.
    NONE...... NOT EXPECTED.  LESS THAN 5% ( 2% FOR TORNADOES)
    LOW....... 5-15% (2-15% FOR TORNADOES)
    MODERATE.. 25-35%
    HIGH...... 45% OR GREATER

SPOTTER ACTIVATION OUTLOOK KEY:
    NOT EXPECTED
    LOW........ ACTIVATION POSSIBLE BUT NOT LIKELY
    MODERATE... POSSIBILITIES ABOUT 50-50
    HIGH....... ACTIVATION LIKELY

FOR MORE INFORMATION ON PROBABILISTIC SEVERE WEATHER OUTLOOKS...GO
TO THE STORM PREDICTION CENTER WEBSITE AT
WWW.SPC.NOAA.GOV/PRODUCTS/OUTLOOK/PROBINFO.HTML.

MYERS

The radar

The Des Moines radar (KDMX), 39 km away, was scanning. The volume nearest the first event began at 00:03 UTC.

Open the radar archive at this moment

Event by event

29 hail, 4 tornado, 3 lightning, 2 thunderstorm wind, 1 flash flood. Local standard time, as filed.

Hail, Warren

When: April 8, 6:01 PM CST
Where: Warren County, Hartford
Measured: 1 in hail
Property damage: $5,000
Reported by: TRAINED SPOTTER
Coordinates: 41.467, -93.417

Hail, Polk

When: April 8, 6:14 PM CST
Where: Polk County, Runnells
Measured: 1 in hail
Property damage: $5,000
Reported by: AMATEUR RADIO
Coordinates: 41.517, -93.367

Hail, Jasper

When: April 8, 6:37 PM CST
Where: Jasper County, Monroe
Measured: 1 in hail
Property damage: $5,000
Reported by: TRAINED SPOTTER
Coordinates: 41.517, -93.100

Hail, Jasper

When: April 8, 6:41 PM CST
Where: Jasper County, Reasnor
Measured: 0.88 in hail
Property damage: $2,000
Reported by: LAW ENFORCEMENT
Coordinates: 41.583, -93.017

Hail, Polk

When: April 8, 6:41 PM CST
Where: Polk County, Polk City
Measured: 1.75 in hail
Property damage: $15,000
Reported by: TRAINED SPOTTER
Coordinates: 41.767, -93.717

Hail, Polk

When: April 8, 6:52 PM CST
Where: Polk County, Grimes
Measured: 1.75 in hail
Property damage: $20,000
Reported by: LAW ENFORCEMENT
Coordinates: 41.683, -93.800

Hail, Polk

When: April 8, 6:54 PM CST
Where: Polk County, Grimes
Measured: 1 in hail
Property damage: $5,000
Reported by: TRAINED SPOTTER
Coordinates: 41.683, -93.800

Hail, Polk

When: April 8, 6:58 PM CST
Where: Polk County, Grimes
Measured: 1 in hail
Property damage: $3,000
Reported by: TRAINED SPOTTER
Coordinates: 41.683, -93.800

Hail, Madison

When: April 8, 7:04 PM CST
Where: Madison County, Earlham
Measured: 1 in hail
Property damage: $4,000
Reported by: LAW ENFORCEMENT
Coordinates: 41.500, -94.133

Hail, Taylor

When: April 8, 7:12 PM CST
Where: Taylor County, Conway
Measured: 1.75 in hail
Property damage: $10,000
Reported by: TRAINED SPOTTER
Coordinates: 40.750, -94.617

Hail, Polk

When: April 8, 7:12 PM CST
Where: Polk County, Urbandale
Measured: 0.75 in hail
Reported by: AMATEUR RADIO
Coordinates: 41.633, -93.717

Hail, Story

When: April 8, 7:38 PM CST
Where: Story County, Maxwell
Measured: 1 in hail
Property damage: $3,000
Reported by: AMATEUR RADIO
Coordinates: 41.883, -93.400

Hail, Ringgold

When: April 8, 7:45 PM CST
Where: Ringgold County, 12 mi W of Mt Ayr
Measured: 1.25 in hail
Property damage: $6,000
Reported by: TRAINED SPOTTER
Coordinates: 40.717, -94.467

Hail, Guthrie

When: April 8, 7:46 PM CST
Where: Guthrie County, Menlo
Measured: 1 in hail
Property damage: $4,000
Reported by: TRAINED SPOTTER
Coordinates: 41.517, -94.417

Hail, Guthrie

When: April 8, 7:56 PM CST
Where: Guthrie County, Menlo
Measured: 1 in hail
Property damage: $5,000
Reported by: TRAINED SPOTTER
Coordinates: 41.517, -94.417

Hail, Dallas

When: April 8, 8:19 PM CST
Where: Dallas County, 3 mi W of Waukee
Measured: 1.75 in hail
Property damage: $10,000
Reported by: AMATEUR RADIO
Coordinates: 41.617, -93.950

Tornado, Dallas

When: April 8, 8:25 PM CST
Where: Dallas County, Waukee
Rating: F0
Path length: 0.2 mi
Path width: 20 yd
Reported by: EMERGENCY MANAGER
Coordinates: 41.617, -93.900

Brief touchdown

Hail, Dallas

When: April 8, 8:27 PM CST
Where: Dallas County, Waukee
Measured: 1 in hail
Property damage: $3,000
Reported by: EMERGENCY MANAGER
Coordinates: 41.617, -93.900

Hail, Marshall

When: April 8, 8:27 PM CST
Where: Marshall County, 6 mi S of Marshalltown
Measured: 0.88 in hail
Property damage: $1,000
Reported by: TRAINED SPOTTER
Coordinates: 41.967, -92.917

Hail, Polk

When: April 8, 8:30 PM CST
Where: Polk County, Grimes
Measured: 1 in hail
Property damage: $4,000
Reported by: TRAINED SPOTTER
Coordinates: 41.683, -93.800

Hail, Polk

When: April 8, 8:34 PM CST
Where: Polk County, 1 mi W of Johnston
Measured: 0.75 in hail
Reported by: LAW ENFORCEMENT
Coordinates: 41.667, -93.717

Lightning, Polk

When: April 8, 8:35 PM CST
Where: Polk County, Johnston
Injuries: 2 direct, 0 indirect
Property damage: $100,000
Reported by: BROADCAST MEDIA
Coordinates: 41.686, -93.573 (the zone’s center; the record gives no point)

Tornado, Decatur

When: April 8, 8:38 PM CST
Where: Decatur County, 5 mi W of Lamoni
Rating: F0
Path length: 0.3 mi
Path width: 30 yd
Property damage: $1,000
Reported by: TRAINED SPOTTER
Coordinates: 40.617, -94.033

Minor damage in rural area with brief touchdown.

Thunderstorm Wind, Decatur

When: April 8, 8:46 PM CST
Where: Decatur County, 3 mi S of Leon
Measured: 61 kt (70 mph)
Injuries: 2 direct, 0 indirect
Property damage: $25,000
Reported by: NEWSPAPER
Coordinates: 40.700, -93.733

Hail, Polk

When: April 8, 8:48 PM CST
Where: Polk County, West Des Moines
Measured: 1.75 in hail
Property damage: $50,000
Reported by: LAW ENFORCEMENT
Coordinates: 41.583, -93.717

Hail, Decatur

When: April 8, 9:05 PM CST
Where: Decatur County, 3 mi N of Grand River
Measured: 1 in hail
Property damage: $2,000
Reported by: TRAINED SPOTTER
Coordinates: 40.867, -93.950

Hail, Ringgold

When: April 8, 9:25 PM CST
Where: Ringgold County, Mt Ayr
Measured: 0.88 in hail
Property damage: $2,000
Reported by: EMERGENCY MANAGER
Coordinates: 40.717, -94.233

Hail, Ringgold

When: April 8, 9:29 PM CST
Where: Ringgold County, Mt Ayr
Measured: 1 in hail
Property damage: $4,000
Reported by: EMERGENCY MANAGER
Coordinates: 40.717, -94.233

Hail, Ringgold

When: April 8, 9:44 PM CST
Where: Ringgold County, Kellerton
Measured: 1 in hail
Property damage: $4,000
Reported by: LAW ENFORCEMENT
Coordinates: 40.700, -94.050

Tornado, Adams

When: April 8, 9:49 PM CST to 9:51 PM CST
Where: Adams County, 1 mi NE of Mt Etna
Rating: F1
Path length: 1 mi
Path width: 50 yd
Injuries: 1 direct, 0 indirect
Property damage: $100,000
Reported by: EMERGENCY MANAGER
Coordinates: 41.133, -94.733

Trailer house overturned and destroyed. Roofs torn off of two sheds.

Tornado, Tama

When: April 8, 9:50 PM CST
Where: Tama County, 2 mi NE of Elberon
Rating: F0
Path length: 0.1 mi
Path width: 20 yd
Reported by: GENERAL PUBLIC
Coordinates: 42.017, -92.283

Brief touchdown.

Hail, Tama

When: April 8, 9:50 PM CST
Where: Tama County, 2 mi NE of Elberon
Measured: 0.88 in hail
Property damage: $1,000
Reported by: GENERAL PUBLIC
Coordinates: 42.017, -92.283

Flash Flood, Ringgold

When: April 8, 10:00 PM CST to April 9, 2:00 AM CST
Where: Ringgold County, 7 mi SE of Mt Ayr
Property damage: $50,000
Reported by: NEWSPAPER
Coordinates: 40.735, -94.244 (the zone’s center; the record gives no point)

Hail, Adair

When: April 8, 10:10 PM CST
Where: Adair County, Orient
Measured: 0.88 in hail
Property damage: $2,000
Reported by: FIRE DEPT/RESCUE SQUAD
Coordinates: 41.200, -94.417

Thunderstorm Wind, Decatur

When: April 8, 10:11 PM CST
Where: Decatur County, Leon
Measured: 71 kt (82 mph)
Injuries: 2 direct, 0 indirect
Property damage: $5,000
Reported by: TRAINED SPOTTER
Coordinates: 40.733, -93.733

Lightning, Decatur

When: April 8, 10:11 PM CST
Where: Decatur County, Leon
Property damage: $5,000
Reported by: NEWSPAPER
Coordinates: 40.738, -93.786 (the zone’s center; the record gives no point)

Lightning, Decatur

When: April 8, 10:30 PM CST
Where: Decatur County, Garden Grove
Property damage: $50,000
Reported by: NEWSPAPER
Coordinates: 40.738, -93.786 (the zone’s center; the record gives no point)

Hail, Wayne

When: April 8, 10:36 PM CST
Where: Wayne County, 6 mi S of Humeston
Measured: 0.88 in hail
Property damage: $2,000
Reported by: TRAINED SPOTTER
Coordinates: 40.783, -93.483

Hail, Wayne

When: April 8, 10:56 PM CST
Where: Wayne County, 3 mi W of Millerton
Measured: 1.75 in hail
Property damage: $5,000
Reported by: LAW ENFORCEMENT
Coordinates: 40.850, -93.350

What these are

Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
Tornado: A violently rotating column of air in contact with the ground and extending from a thunderstorm, filed with its path, width and Fujita or Enhanced Fujita rating from the damage survey.
Lightning: A lightning strike that killed, injured or caused damage.
Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Iowa in 2001 Every state in 2001 This day in weather history The tornado archive for Iowa, 2001 Warnings in Iowa, April 2001

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5236103, 5236104, 5236105, 5236106, 5236107, 5236108, 5236109, 5236110, 5236111, 5236112, 5236113, 5236114, 5236115, 5236116, 5236117, 5236118, 5236119, 5236360, 5236452, 5236453, 5236454, 5236455, 5238902, 5238916, 5238903, 5238904, 5238905, 5238906, 5238907, 5238908, 5238909, 5238910, 5238917, 5238911, 5238912, 5238913, 5238918, 5238914, 5238915.