Iowa, 2002

Damaging Wind in Iowa, July 5, 2002

July 5, 2002 · NWS DMX · 1 event in 1 county or zone

A very unstable airmass was in place over Iowa as deep moisture was in place under an upper level sub-tropical ridge of high pressure. During the late afternoon and early evening hours thunderstorms developed over Iowa.

Where it happened

Every event with a place to put it. 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
$5,000
Crop damage
None recorded
Events
1

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 very unstable airmass was in place over Iowa as deep moisture was in place under an upper level sub-tropical ridge of high pressure. During the late afternoon and early evening hours thunderstorms developed over Iowa. The storms were basically tropical in nature, producing mainly heavy rainfall. One of the storms became severe over Poweshiek County as it produced a downburst over the town of Montezuma.

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 Jul 5, 2:30 PM CST, 4 hours 22 minutes earlier.

Area forecast discussion, Jul 5, 2:30 PM CST, 4 hours 22 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
330 PM CDT FRI JUL 5 2002

RATHER BUSY WITH ON-GOING CONVECTION. DVLPMT OCCURRED QUITE RPDLY
ONCE CONVECTIVE TMP WAS REACHED. OUTFLOWS ARE THE DRIVING MECHANISM
WITH NMRS COLLISIONS PRODUCING NEW CONVECTION IN WK FLOW
ENVIRONMENT. ISOLD SPOTS SEEING 2-3IN RAINS...WHICH FOR THE MOST
PART...CAN BE ENDURED. PRIMARY CONCERN HAS BEEN WNDS FROM COLLASPING
STORMS...WHICH HAVE BEEN BEHAVING WITH G40-45 MPH. SURPRISINGLY...A
FEW STORMS HAVE HAD DECENT ROTATION.

OVERALL SCENARIO HAS NOT AND WIL NOT CHG UNTIL WE GET A FRESH AMS IN
HERE. LOOKING FOR A DOWNWARD TREND THIS EVENING WITH NIL TRW AFT
MIDN. SIMILAR SITUATION XPCD TMR WITH MIDDAY DVLPMT. DITTO FOR
MONDAY...XCP BTR FORCING ANTICIPATED...AND HENCE BTR ORGANIZATION.
BNDRY GRADLY SINKS SWD ACRS IA ON TUE FOLLOWED BY LOWER HUMIDITIES
AND NEG PCPN...WHICH IS WELL TRENDED IN CUR FCSTS. LTL CHG IN TMPS
THRU DAY 3.

.DSM...NONE
MYERS

The radar

The Des Moines radar (KDMX), 100 km away, was scanning. The volume nearest the first event began at 00:53 UTC.

Open the radar archive at this moment

Event by event

1 thunderstorm wind. Local standard time, as filed.

Thunderstorm Wind, Poweshiek

When
July 5, 6:52 PM CST
Where
Poweshiek County, Montezuma
Measured
50 kt (58 mph)
Property damage
$5,000
Reported by
AWOS,ASOS,MESONET,ETC
Coordinates
41.583, -92.533

What these are

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 2002Every state in 2002This day in weather historyWarnings in Iowa, July 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: 5304508.