Iowa, 2004

Flash Flood and Hail in Iowa, May 27, 2004

May 27, 2004 · NWS DMX · 18 events in 4 counties and zones

A weak trough of low pressure was over southern Iowa as a reinforcing cold front dropped southeast into the state. The airmass was moderately unstable with dew point readings in the 60s.

Where it happened

Every event with a place to put it; 1 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
0
Property damage
$54,000
Crop damage
$235,000
Events
18

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.

A weak trough of low pressure was over southern Iowa as a reinforcing cold front dropped southeast into the state. The airmass was moderately unstable with dew point readings in the 60s. Surface low tracked east across central Missouri during the mid part of the day. Thunderstorms erupted across southern Iowa. They formed into a line and became severe. The main severe weather mode was hail. There were numerous reports of three quarter inch to one and one quarter inch diameter hail over far southern Iowa. Golf ball size hail pelted parts of Decatur County. The combination of one inch diameter hail and 50 MPH winds caused considerable crop damage in Taylor County. A swath 8 miles long and 3 miles wide was destroyed in an area extending from the hamlet of Siam, ease-southeast to the county border south of Bedford. Heavy rainfall at the rage of of one to two inches per hour resulted in flash flooding in Ringgold County with water running over roads north of Mount Ayr.

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 May 27, 2:52 AM CST, 7 hours 20 minutes earlier.

Area forecast discussion, May 27, 2:52 AM CST, 7 hours 20 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
352 AM CDT THU MAY 27 2004

.DISCUSSION...
NRN BRANCH S/W DID MANAGE TO GEN UP A COUPLE OF CELLS IN NRN IA
OVRNGT. ACTUALLY LESS THAN ANTICIPATED. ELSEWHERE...LOW LVL ST CONTS
TO XPND ACRS THE S AND INTO THE CNTRL COUNTIES WHICH SHOULD CONT
THRU THE ERLY MRNG. FLOW SHOULD START VEERING IN THE 12-15Z TIME
FRAME PER RUC...SHUNTING ST SEWRD. THUS A PD OF LOW CLDS THIS MRNG.
WDSPRD AC/AS IN ERN NEB AHD NXT SHEARING WAVE OVR SWRN SD AND NWRN
NEB LOOKS TO BE WRMG A BIT NOW AS WELL. SO STILL LOOKING FOR
SUNSHINE THAT AFTN WITH COMFORTABLE TEMPS. WE ARE WATCHING THE TSTMS
XPND NWD A BIT IN XTRM NERN KS AND BLV THOSE WL STAY JUST S OF THE
BDR IN NRN MO AS FLOW IS WLY.

MDLS ARE STILL KEYING IN A WKEND SURGE OF WARMTH AND MOISTURE NWD AS
LEE SIDE CYCLONGENESIS GETS UNDERWAY AHD OF A SGFNT WCST TROF. S/W
RDGG BUILDS OVER IA FRI NGT AND SAT...CROSSING THE MS RVR BY MIDDAY.
RAPID DESTABILIZATION SHOULD THEN TAKE PLACE ALG THE BNDRY TO OUR W
IN THE MO RVR VLY...AND PROGRESS EWD OVRNGT. ANY WRMFNTL ACTION
SHOULD BE WELL N/NW OF US FRI/FRI NGT. FNT BLOWS THRU SUN WITH A
DCRG THREAT OF PCPN THRU THE DAY. CD TMPS ALF SHOULD BE ENOUGH FOR
AFTN TSTM THREAT ON MONDAY. THE REST OF NXT WEEK LOOKS RATHER
COOLISH IN MDT TO STG NWLY FLOW WITH A MAJOR PCPN THREAT TO OUR S.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...NONE

&&

MYERS
Hazardous weather outlook, May 27, 10:12 AM CST, 0 minutes before
HAZARDOUS WEATHER OUTLOOK...UPDATE
NATIONAL WEATHER SERVICE DES MOINES IA
1112 AM CDT THU MAY 27 2004

IAZ007-017-026>028-037>039-049-050-061-062-074-075-281100-
BLACK HAWK-BREMER-BUTLER-CERRO GORDO-FRANKLIN-GRUNDY-HARDIN-JASPER-
MAHASKA-MARION-MARSHALL-POWESHIEK-TAMA-WORTH-
1112 AM CDT THU MAY 27 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL IOWA EAST OF INTERSTATE
35.

.DAY ONE...TODAY AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH THURSDAY

THUNDERSTORMS ARE EXPECTED SATURDAY NIGHT AND SUNDAY WITH THE THREAT
OF SEVERE WEATHER SATURDAY NIGHT...MAINLY WEST OF THE AREA.

IN ADDITION...WIDESPREAD MODERATE RAIN WILL OCCUR SATURDAY
NIGHT...WITH LOCALLY HEAVY RAINFALL QUITE POSSIBLE.  THIS RAINFALL
COULD RENEW A FLOOD THREAT.

.SPOTTER ACTIVATION STATEMENT...

SPOTTER ACTIVATION IS POSSIBLE SATURDAY NIGHT INTO EARLY SUNDAY.

IAZ004>006-015-016-023>025-033>036-044>048-057>060-070>073-281100-
ADAIR-AUDUBON-BOONE-CALHOUN-CARROLL-CASS-CRAWFORD-DALLAS-EMMET-
GREENE-GUTHRIE-HAMILTON-HANCOCK-HUMBOLDT-KOSSUTH-MADISON-PALO ALTO-
POCAHONTAS-POLK-SAC-STORY-WARREN-WEBSTER-WINNEBAGO-WRIGHT-
1112 AM CDT THU MAY 27 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL IOWA ALONG AND WEST OF
INTERSTATE 35.

.DAY ONE...TODAY AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH THURSDAY

THUNDERSTORMS ARE EXPECTED SATURDAY NIGHT AND SUNDAY WITH A THREAT OF
SEVERE WEATHER SATURDAY NIGHT INTO SUNDAY.

IN ADDITION...WIDESPREAD MODERATE RAIN WILL OCCUR SATURDAY
NIGHT...WITH LOCALLY HEAVY RAINFALL QUITE POSSIBLE.  THIS RAINFALL
COULD RENEW A FLOOD THREAT.

.SPOTTER ACTIVATION STATEMENT...

SPOTTER ACTIVATION IS POSSIBLE SATURDAY NIGHT INTO SUNDAY.

IAZ081>083-092>094-281100-
ADAMS-CLARKE-DECATUR-RINGGOLD-TAYLOR-UNION-
1112 AM CDT THU MAY 27 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR FAR SOUTHWEST PORTIONS
OF CENTRAL IOWA.

.DAY ONE...TODAY AND TONIGHT

ISOLATED SEVERE THUNDERSTORMS WITH LARGE HAIL AND LOCALLY EXCESSIVE
RAINFALL ARE POSSIBLE THROUGH EARLY AFTERNOON.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH THURSDAY

THUNDERSTORMS ARE EXPECTED SATURDAY NIGHT AND SUNDAY WITH A THREAT OF
SEVERE WEATHER SATURDAY NIGHT INTO SUNDAY.

IN ADDITION...WIDESPREAD MODERATE RAIN WILL OCCUR SATURDAY
NIGHT...WITH LOCALLY HEAVY RAINFALL QUITE POSSIBLE.  THIS RAINFALL
COULD RENEW A FLOOD THREAT.

.SPOTTER ACTIVATION STATEMENT...

SPOTTER ACTIVATION IS POSSIBLE TODAY AND AGAIN SATURDAY NIGHT INTO
SUNDAY.

IAZ084>086-095>097-281100-
APPANOOSE-DAVIS-LUCAS-MONROE-WAPELLO-WAYNE-
1112 AM CDT THU MAY 27 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR FAR SOUTHEAST PORTIONS CENTRAL
IOWA.

.DAY ONE...TODAY AND TONIGHT

ISOLATED SEVERE THUNDERSTORMS WITH LARGE HAIL AND LOCALLY EXCESSIVE
RAINFALL ARE POSSIBLE THROUGH MID AFTERNOON.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH THURSDAY

THUNDERSTORMS ARE EXPECTED SATURDAY NIGHT AND SUNDAY WITH THE THREAT
OF SEVERE WEATHER SATURDAY NIGHT...MAINLY WEST OF THE AREA.

IN ADDITION...WIDESPREAD MODERATE RAIN WILL OCCUR SATURDAY
NIGHT...WITH LOCALLY HEAVY RAINFALL QUITE POSSIBLE.  THIS RAINFALL
COULD RENEW A FLOOD THREAT.

.SPOTTER ACTIVATION STATEMENT...

SPOTTER ACTIVATION IS POSSIBLE TODAY AND AGAIN SATURDAY NIGHT INTO
EARLY SUNDAY.

KULA

The radar

The Des Moines radar (KDMX), 151 km away, was scanning. The volume nearest the first event began at 16:10 UTC.

Open the radar archive at this moment

Event by event

15 hail, 2 thunderstorm wind, 1 flash flood. Local standard time, as filed.

Hail, Taylor

When
May 27, 10:12 AM CST
Where
Taylor County, 11 mi N of New Market
Measured
0.88 in hail
Property damage
$1,000
Crop damage
$5,000
Reported by
EMERGENCY MANAGER
Coordinates
40.600, -94.717

Hail, Taylor

When
May 27, 10:35 AM CST
Where
Taylor County, 3 mi WSW of Lenox
Measured
1 in hail
Property damage
$2,000
Crop damage
$5,000
Reported by
TRAINED SPOTTER
Coordinates
40.900, -94.900

Hail, Decatur

When
May 27, 10:36 AM CST
Where
Decatur County, Decatur City
Measured
0.75 in hail
Crop damage
$15,000
Reported by
GENERAL PUBLIC
Coordinates
40.867, -94.600

Hail, Decatur

When
May 27, 10:40 AM CST
Where
Decatur County, Leon
Measured
1.25 in hail
Property damage
$5,000
Crop damage
$5,000
Reported by
TRAINED SPOTTER
Coordinates
40.733, -93.817

Hail, Decatur

When
May 27, 10:40 AM CST
Where
Decatur County, 1 mi N of Leon
Measured
1 in hail
Property damage
$2,000
Crop damage
$5,000
Reported by
TRAINED SPOTTER
Coordinates
40.733, -93.733

Hail, Decatur

When
May 27, 10:45 AM CST
Where
Decatur County, 1 mi W of Leon
Measured
0.75 in hail
Crop damage
$5,000
Reported by
EMERGENCY MANAGER
Coordinates
40.750, -93.733

Hail, Decatur

When
May 27, 10:47 AM CST
Where
Decatur County, Leon
Measured
0.88 in hail
Property damage
$1,000
Crop damage
$5,000
Reported by
TRAINED SPOTTER
Coordinates
40.733, -93.750

Hail, Ringgold

When
May 27, 10:52 AM CST
Where
Ringgold County, 1 mi NW of Diagonal
Measured
0.75 in hail
Crop damage
$5,000
Reported by
TRAINED SPOTTER
Coordinates
40.733, -93.733

Hail, Decatur

When
May 27, 10:52 AM CST
Where
Decatur County, 1 mi N of Decatur City
Measured
1.75 in hail
Property damage
$10,000
Crop damage
$5,000
Reported by
TRAINED SPOTTER
Coordinates
40.817, -94.350

Hail, Wayne

When
May 27, 11:26 AM CST
Where
Wayne County, Allerton
Measured
0.88 in hail
Property damage
$1,000
Crop damage
$5,000
Reported by
POST OFFICE
Coordinates
40.750, -93.817

Hail, Decatur

When
May 27, 11:45 AM CST
Where
Decatur County, 6 mi ESE of Leon
Measured
0.88 in hail
Property damage
$1,000
Crop damage
$5,000
Reported by
TRAINED SPOTTER
Coordinates
40.700, -93.367

Flash Flood, Ringgold

When
May 27, 11:45 AM CST to 1:15 PM CST
Where
Ringgold County, 5 mi NNE of Mt Ayr
Property damage
$20,000
Crop damage
$5,000
Reported by
LAW ENFORCEMENT
Coordinates
40.700, -93.633

Hail, Taylor

When
May 27, 12:06 PM CST
Where
Taylor County, 7 mi S of New Market
Measured
1 in hail
Property damage
$2,000
Crop damage
$5,000
Reported by
TRAINED SPOTTER
Coordinates
40.737, -94.696 (the zone’s center; the record gives no point)

Thunderstorm Wind, Taylor

When
May 27, 12:08 PM CST
Where
Taylor County, 8 mi WSW of Bedford Arpt
Measured
52 kt (60 mph) estimated gust
Property damage
$1,000
Reported by
TRAINED SPOTTER
Coordinates
40.633, -94.900

Hail, Wayne

When
May 27, 12:15 PM CST
Where
Wayne County, 3 mi W of Promise City
Measured
0.75 in hail
Crop damage
$5,000
Reported by
TRAINED SPOTTER
Coordinates
40.583, -94.850

Hail, Taylor

When
May 27, 12:17 PM CST
Where
Taylor County, 8 mi WSW of Bedford Arpt
Measured
0.88 in hail
Property damage
$1,000
Crop damage
$5,000
Reported by
TRAINED SPOTTER
Coordinates
40.750, -93.200

Thunderstorm Wind, Taylor

When
May 27, 12:18 PM CST
Where
Taylor County, 5 mi SSW of Bedford
Measured
61 kt (70 mph) estimated gust
Property damage
$5,000
Reported by
TRAINED SPOTTER
Coordinates
40.583, -94.850

Hail, Taylor

When
May 27, 12:22 PM CST
Where
Taylor County, 5 mi S of Bedford
Measured
1 in hail
Property damage
$2,000
Crop damage
$150,000
Reported by
TRAINED SPOTTER
Coordinates
40.600, -94.750

What these are

Hail
Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
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.
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.

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

The same day elsewhere

More

Every storm in Iowa in 2004Every state in 2004This day in weather historyWarnings in Iowa, May 2004

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: 5393551, 5393552, 5393553, 5393554, 5393555, 5393556, 5393557, 5393558, 5393559, 5393560, 5393561, 5393562, 5393563, 5393564, 5393565, 5393566, 5393567, 5394421.