Iowa, 2002

Flood and Hail in Iowa, September 18, 2002

September 18, 2002 · NWS DVN · 15 events in 3 counties and zones

A cluster of thunderstorms weakened while moving into Northeast Iowa toward the noon hour near and northwest of Cedar Rapids. An isolated single cell continued to track east however, and with the mid afternoon heating intensified over Jones County.

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

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The toll

Deaths
0
Injuries
0
Property damage
$20 million
Crop damage
None recorded
Events
15

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 DVN wrote it up.

A cluster of thunderstorms weakened while moving into Northeast Iowa toward the noon hour near and northwest of Cedar Rapids. An isolated single cell continued to track east however, and with the mid afternoon heating intensified over Jones County. The storm eventually became a high precipitation supercell as it moved into Jackson County producing a swath of damaging hail up to baseball size and winds of 70 to 80 mph. The city of Maquoketa was hardest hit as most residents reported some property damage. Nearly 1,000 new and used vehicles from several automotive dealerships suffered hail damage. One owner of a car dealership was quoted as saying that the cars on his lot looked like they had chicken pox. The pea to golf ball sized hail was so frequent, lasting nearly 20 minutes, that melting remnants left a nearly 2 inch thick sheet of ice in the bed of one pickup truck. Damage to the city of Maquoketa alone was estimated at nearly 20 million dollars.

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 Quad Cities, IA wrote its last area forecast discussion before the first event at Sep 18, 1:36 AM CST, 11 hours 21 minutes earlier.

Area forecast discussion, Sep 18, 1:36 AM CST, 11 hours 21 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
236 AM CDT WED SEP 18 2002

SYNOPTIC PICTURE THIS MORNING SHOWS COLD FRONT FROM CENTRAL DAKOTAS
INTO THE TX PANHANDLE.  AT 500H A PRONOUNCED SHORT WAVE IS LIFTING
THROUGH THE FORECAST AREA...TRIGGERING PRECIP ACROSS NORTH CENTRAL
ILLINOIS.  DRY AIR AT MID LEVELS IS INHIBITING PRECIP IN OUR AREA.
A LINE OF PRECIP FROM EASTERN SD TO OMA HAS FIRED IN THE PAST FEW
HOURS ALONG A PSEUDO WARM FRONT.

THE PRIMARY FORECAST CONCERN THIS PACKAGE IS IN FIRST 48 HOURS WITH
VARIOUS CHANCES OF PRECIP...POSSIBLE HEAVY LATE TONIGHT AND THURSDAY.
ALSO OF IMPORTANCE IS COOL DOWN FRIDAY THROUGH THE WEEKEND.

MODELS INITIALIZED WELL AT 00Z ON THE PLAINS COLD FRONT. THE AVN AND
ETA HAD BEST HANDLE ON PRECIP 00Z-06Z.

SHORT-RANGE MODELS AGREE ON LIFTING SHORT WAVE NORTH OF THE AREA BY
SUNRISE. THE COLD FRONT MOVES THRU IN TWO PUNCHES...WITH THE FIRST
PUNCH THURSDAY NIGHT AND THE SECOND FRIDAY NIGHT.  A SURFACE WAVE LIFTS
NORTH ALONG THE FRONT EITHER THURSDAY OR THURSDAY NIGHT...WITH THE AVN
PICKING THE FIRST TIME AND THE ETA THE SECOND.  THE 500H TROF ALSO
MOVES THRU THE AREA IN TWO WAVES...WITH THE FIRST FRIDAY AFTERNOON AND
THE SECOND SATURDAY EVENING.  VVS ARE STRONG ON-AND-OFF THRU
THURSDAY...WITH UPPER SUPPORT THURSDAY AS A 115 KT JET MOVES OVER.
FIRST PUNCH OF COOLER AIR WILL BE THURSDAY NIGHT AND FRIDAY...WITH
SECOND PUNCH LATE FRIDAY NIGHT AND SATURDAY.

WILL STAY CLOSE TO CURRENT FORECAST. MAY UP POPS A BIT FOR TODAY...AS
ISENTROPIC LIFT SATURATES THE COLUMN.  WILL KEEP HIGH POPS FOR TONIGHT
AND THURSDAY...AND RAISE A NOTCH THURSDAY NIGHT AS UPPER JET SUPPORT
WILL BE IN PLAY.  TEMPS ARE ON TRACK INITIALLY...BUT WILL HAVE TO
RAISE FOR THURSDAY...DUE TO SLOWING OF COLD FRONT.

.DVN...
IA...NONE.
IL...NONE.
MO...NONE.

REA

The radar

The Quad Cities radar (KDVN), 81 km away, was scanning. The volume nearest the first event began at 18:58 UTC.

Open the radar archive at this moment

Event by event

9 hail, 5 thunderstorm wind, 1 flood. Local standard time, as filed.

Hail, Jones

When
September 18, 12:57 PM CST
Where
Jones County, Anamosa
Measured
0.88 in hail
Reported by
TRAINED SPOTTER
Coordinates
42.117, -91.283

Hail, Jones

When
September 18, 12:58 PM CST
Where
Jones County, Anamosa
Measured
1 in hail
Reported by
TRAINED SPOTTER
Coordinates
42.117, -91.283

Thunderstorm Wind, Jones

When
September 18, 1:14 PM CST
Where
Jones County, 4 mi N of Wyoming
Measured
61 kt (70 mph)
Reported by
TRAINED SPOTTER
Coordinates
42.117, -91.000

Hail, Jones

When
September 18, 1:21 PM CST
Where
Jones County, Wyoming
Measured
1 in hail
Reported by
TRAINED SPOTTER
Coordinates
42.067, -91.000

Thunderstorm Wind, Jones

When
September 18, 1:21 PM CST
Where
Jones County, Wyoming
Measured
61 kt (70 mph)
Reported by
TRAINED SPOTTER
Coordinates
42.067, -91.000

Hail, Jones

When
September 18, 1:25 PM CST
Where
Jones County, Wyoming
Measured
1.25 in hail
Reported by
TRAINED SPOTTER
Coordinates
42.067, -91.000

Flood, Jones

When
September 18, 1:30 PM CST
Where
Jones County, Wyoming
Reported by
TRAINED SPOTTER
Coordinates
42.121, -91.131 (the zone’s center; the record gives no point)

Hail, Jackson

When
September 18, 1:40 PM CST to 2:00 PM CST
Where
Jackson County, Maquoketa
Measured
2.75 in hail
Property damage
$20 million
Reported by
NEWSPAPER
Coordinates
42.067, -90.683

Thunderstorm Wind, Jackson

When
September 18, 1:40 PM CST to 2:00 PM CST
Where
Jackson County, Maquoketa
Measured
61 kt (70 mph)
Reported by
NEWSPAPER
Coordinates
42.067, -90.683

Thunderstorm Wind, Jackson

When
September 18, 1:42 PM CST
Where
Jackson County, Baldwin
Measured
70 kt (81 mph)
Reported by
TRAINED SPOTTER
Coordinates
42.067, -90.850

Hail, Jackson

When
September 18, 1:42 PM CST
Where
Jackson County, Baldwin
Measured
2.5 in hail
Reported by
TRAINED SPOTTER
Coordinates
42.067, -90.850

Hail, Jackson

When
September 18, 1:51 PM CST
Where
Jackson County, 1 mi W of Maquoketa
Measured
2.75 in hail
Reported by
TRAINED SPOTTER
Coordinates
42.067, -90.700

Hail, Jackson

When
September 18, 1:51 PM CST
Where
Jackson County, Maquoketa
Measured
1 in hail
Reported by
TRAINED SPOTTER
Coordinates
42.067, -90.683

Thunderstorm Wind, Clinton

When
September 18, 2:20 PM CST
Where
Clinton County, Goose Lake
Measured
61 kt (70 mph)
Reported by
AMATEUR RADIO
Coordinates
41.967, -90.400

Hail, Clinton

When
September 18, 2:20 PM CST
Where
Clinton County, Goose Lake
Measured
1 in hail
Reported by
AMATEUR RADIO
Coordinates
41.967, -90.400

What these are

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

More

Every storm in Iowa in 2002Every state in 2002This day in weather historyWarnings in Iowa, September 2002

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: 5320332, 5320333, 5320334, 5320335, 5320336, 5320337, 5320338, 5320345, 5320346, 5320339, 5320340, 5320341, 5320342, 5320343, 5320344.