Flooding in Iowa, May 21 to 28, 2001

Name: Flooding in Iowa, May 21 to 28, 2001
Start: 2001-05-21T18:00
End: 2001-05-28T12:00
Location: Iowa

May 21 to 28, 2001 · NWS DMX · 14 events in 14 counties and zones

Where it happened

Every event with a place to put it; 14 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: $420,000
Crop damage: None recorded
Events: 14

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.

For the first time in well over a month all forecast points in the HSA fell below flood stage on May 18th, as Estherville finally fell below flood stage. The respite was short-lived however, as heavy rains fell on the 20th- 21st over mainly the western and northern half of the HSA. Mean areal rainfall of 1 to as much as 3 inches was estimated over the central and northern portions of the Des Moines and Iowa river basins. The Estherville ASOS station measured 2.95" in 24 hours; other significant reports from NWS cooperative stations included 2.52" at Jefferson, 2.37" at Harcourt, 2.10" at Rockwell City, 2.06" at Jewell and 1.97" at Iowa Falls. These rains caused renewed rises to flood stage or higher on rivers in the Raccoon and Des Moines basin. An extended period of unusually cool weather began on the 21st and lasted through the duration of May, as a deep upper level trough became anchored over the eastern half of the U.S. A record low maximum temperature record was set on the 23rd at Des Moines, with a high temperature of 53oF, which broke a 1976 record of 60oF. Scattered showers fell over most of the HSA during most of this period as the extremely cool temperatures aloft combined with strong May sun to create very unstable conditions. Most locations picked up some rainfall, but amounts were quite variable and generally less than a half-inch on any one day, with a few notable exceptions. These included 1.16" at Eldora (ELDI4) and 1.15" at Steamboat Rock (STBI4) for the 24 hours ending on the 25th. The very slow moving system continued to produce precipitation on the 25th, including some locally heavy showers especially over central Iowa.

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 21, 2:40 PM CST, 3 hours 20 minutes earlier.

Area forecast discussion, May 21, 2:40 PM CST, 3 hours 20 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
340 PM CDT MON MAY 21 2001

FORECAST PROOBLEMS FOR THIS PACKAGE ARE PRECIP CHANCES AND TO A
LESSER DEGREE...TEMPS.  WATER VAPOR IMAGERY CONFIRMS THE UA ANALYSIS
OF A VERY WELL DEFINED LONGWAVE TROUGH PARKED OVER THE UPPER MIDWEST.
THIS WL KEEP NRLY FLOW AND CAA OVER THE STATE THROUGH MOST OF THE
FORECAST PERIOD.  THIS PATTERN IS MORE LIKE OCTOBER THAN MAY BUT
WITH WEAK SHORTWAVE "RIPPLES" IMBEDDED IN THE FLOW IT WILL BE TOUGH
TO PICK OUT TIMING OF PRECIP OR EVEN IF IT WILL RAIN.  SINCE THERE
IS LITTLE CHANGE IN THE AIRMASS OR THE MAIN FEATURES OVER THE NEXT
48 HOURS I THINK PERSISTENCE IS A PRETTY GOOD RULE THEREFORE I AM
KEEPING ISOLATED TO WIDELY SCATTERED SHOWERS GOING IN THE FORECAST
THROUGH TUESDAY NIGHT.  MUCH LIKE TODAY...THEY WILL DEVELOP IN THE
LATE MORNING AND AFTERNOON AND DIE OUT IN THE EVENING.  I DON'T
EXPECT TO SEE MUCH IN THE WAY OF RAINFALL AMOUNTS THROUGH TUESDAY
NIGHT.  ON WEDNESDAY A STRONGER SHORTWAVE DROPS DOWN AS THE LOW
PULLS SE AND THIS ONE IS OUR BEST CHANCE FOR A RAIN-MAKER.  A HAVE
GONE ABOVE GUIDANCE ON WEDNESDAY AND WEDNESDAY NIGHT BUT AGAIN THE
MODELS DON'T INDICATE A LOT OF RAIN WITH THIS.

AS FOR TEMPS...THIS WILL DEPEND A LOT ON CLOUD COVER.  I EXPECT TO
SEE A LOT OF COLD AIR SC DEVELOPMENT DURING THE DAY HENCE I AM
OPTING FOR COOLER HIGHS.  THE PROBLEM IS WHETHER OR NOT WE CLEAR OUT
DURING THE EVENING AND OVERNIGHT HOURS.  IT WOULD APPEAR THAT AT
LEAST PART OF THE EVENINGS WOULD BE CLOUDY BUT WITHOUT A SHORWAVE
PASSING THROUGH...THE SOUNDINGS DID NOT SUPPORT CLOUDY SKIES
OVERNIGHT.  I WENT ON THE COOELR SIDE OF MOS AND EVEN A BIT BELOW
MOS MAINLY ACROSS THE NORTH.

THE EXTENDED IS SHOWING A SLOW SEND OFF TO THE LOW WHICH EVENTUALLY
(BY SATURDAY) MAKES IT INTO MICHIGAN SO I KEPT A COOL FORECAST WITH
ISOLATED SHOWERS GOING THROUGH EARLY FRIDAY.

.DSM...NONE

FAB

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

14 flood. Local standard time, as filed.

Flood, Calhoun

When: May 21, 6:00 PM CST to May 28, 12:00 PM CST
Where: Calhoun forecast zone
Property damage: $30,000
Reported by: OFFICIAL NWS OBS.
Coordinates: 42.385, -94.640 (the zone’s center; the record gives no point)

Flood, Carroll

When: May 21, 6:00 PM CST to May 28, 12:00 PM CST
Where: Carroll forecast zone
Property damage: $30,000
Reported by: OFFICIAL NWS OBS.
Coordinates: 42.036, -94.861 (the zone’s center; the record gives no point)

Flood, Dallas

When: May 21, 6:00 PM CST to May 28, 12:00 PM CST
Where: Dallas forecast zone
Property damage: $30,000
Reported by: OFFICIAL NWS OBS.
Coordinates: 41.685, -94.040 (the zone’s center; the record gives no point)

Flood, Emmet

When: May 21, 6:00 PM CST to May 28, 12:00 PM CST
Where: Emmet forecast zone
Property damage: $30,000
Reported by: OFFICIAL NWS OBS.
Coordinates: 43.378, -94.678 (the zone’s center; the record gives no point)

Flood, Greene

When: May 21, 6:00 PM CST to May 28, 12:00 PM CST
Where: Greene forecast zone
Property damage: $30,000
Reported by: OFFICIAL NWS OBS.
Coordinates: 42.036, -94.397 (the zone’s center; the record gives no point)

Flood, Hamilton

When: May 21, 6:00 PM CST to May 28, 12:00 PM CST
Where: Hamilton forecast zone
Property damage: $30,000
Reported by: OFFICIAL NWS OBS.
Coordinates: 42.384, -93.707 (the zone’s center; the record gives no point)

Flood, Hancock

When: May 21, 6:00 PM CST to May 28, 12:00 PM CST
Where: Hancock forecast zone
Property damage: $30,000
Reported by: OFFICIAL NWS OBS.
Coordinates: 43.082, -93.734 (the zone’s center; the record gives no point)

Flood, Humboldt

When: May 21, 6:00 PM CST to May 28, 12:00 PM CST
Where: Humboldt forecast zone
Property damage: $30,000
Reported by: OFFICIAL NWS OBS.
Coordinates: 42.777, -94.207 (the zone’s center; the record gives no point)

Flood, Kossuth

When: May 21, 6:00 PM CST to May 28, 12:00 PM CST
Where: Kossuth forecast zone
Property damage: $30,000
Reported by: OFFICIAL NWS OBS.
Coordinates: 43.204, -94.207 (the zone’s center; the record gives no point)

Flood, Palo Alto

When: May 21, 6:00 PM CST to May 28, 12:00 PM CST
Where: Palo Alto forecast zone
Property damage: $30,000
Reported by: OFFICIAL NWS OBS.
Coordinates: 43.082, -94.678 (the zone’s center; the record gives no point)

Flood, Pocahontas

When: May 21, 6:00 PM CST to May 28, 12:00 PM CST
Where: Pocahontas forecast zone
Property damage: $30,000
Reported by: OFFICIAL NWS OBS.
Coordinates: 42.734, -94.679 (the zone’s center; the record gives no point)

Flood, Sac

When: May 21, 6:00 PM CST to May 28, 12:00 PM CST
Where: Sac forecast zone
Property damage: $30,000
Reported by: OFFICIAL NWS OBS.
Coordinates: 42.386, -95.105 (the zone’s center; the record gives no point)

Flood, Webster

When: May 21, 6:00 PM CST to May 28, 12:00 PM CST
Where: Webster forecast zone
Property damage: $30,000
Reported by: OFFICIAL NWS OBS.
Coordinates: 42.428, -94.182 (the zone’s center; the record gives no point)

Flood, Winnebago

When: May 21, 6:00 PM CST to May 28, 12:00 PM CST
Where: Winnebago forecast zone
Property damage: $30,000
Reported by: OFFICIAL NWS OBS.
Coordinates: 43.378, -93.734 (the zone’s center; the record gives no point)

What these are

Flood: Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.

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 Warnings in Iowa, May 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: 5242555, 5242556, 5242557, 5242558, 5242559, 5242560, 5242629, 5242630, 5242631, 5242632, 5242633, 5242634, 5242635, 5242636.