Iowa, 1998

Flooding and Hail in Iowa, August 14, 1998

August 14, 1998 · NWS DMX · 5 events in 3 counties and zones

A marginally unstable airmass was located over Iowa with dew point temperatures in the low 70s. A cold front moved into the northwest corner of the state during the late afternoon hours.

Where it happened

Every event with a place to put it; 2 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
$58,000
Crop damage
$86,000
Events
5

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 marginally unstable airmass was located over Iowa with dew point temperatures in the low 70s. A cold front moved into the northwest corner of the state during the late afternoon hours. A scattered line of thunderstorms developed along the front during the late afternoon into the evening hours. The storms produced little in the way of wind and very heavy rainfall. Reports indicated pea to small marble size hail in the Crawford County areas. In Deloit, 1.75 inches of rain fell in 45 minutes. This caused street flooding in the area. Heavy rain also fell to the north of the Deloit area in Sac County. This resulted in some minor flooding in the county with the Odebolt Creek rising above bankful. As the storms were developing, a few of them produced hail and high winds over west central Sac County. Golf ball size hail and winds of up to 70 MPH were reported north of Odebolt. During the late evening hours the storms formed into clusters with several cell mergers. A report of dime size hail was received from Ankeny in Polk County.

The radar

The Des Moines radar (KDMX), 146 km away, was scanning. The volume nearest the first event began at 01:29 UTC.

Open the radar archive at this moment

Event by event

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

Thunderstorm Wind, Sac

When
August 14, 7:30 PM CST
Where
Sac County, 3 mi N of Odebolt
Measured
61 kt (70 mph)
Property damage
$3,000
Crop damage
$25,000
Reported by
NEWSPAPER
Coordinates
42.370, -95.270

Hail, Sac

When
August 14, 7:45 PM CST
Where
Sac County, 3 mi N of Odebolt
Measured
1.75 in hail
Property damage
$5,000
Crop damage
$50,000
Reported by
NEWSPAPER
Coordinates
42.370, -95.270

Flood, Sac

When
August 14, 8:00 PM CST to 10:30 PM CST
Where
Sac County, Odebolt
Property damage
$25,000
Crop damage
$5,000
Reported by
NEWSPAPER
Coordinates
42.386, -95.105 (the zone’s center; the record gives no point)

Flood, Crawford

When
August 14, 8:10 PM CST to 10:30 PM CST
Where
Crawford County, Deloit
Property damage
$25,000
Crop damage
$5,000
Reported by
TRAINED SPOTTER
Coordinates
42.037, -95.382 (the zone’s center; the record gives no point)

Hail, Polk

When
August 14, 10:38 PM CST
Where
Polk County, Ankeny
Measured
0.75 in hail
Crop damage
$1,000
Reported by
LAW ENFORCEMENT
Coordinates
41.730, -93.620

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.
Hail
Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
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 1998Every state in 1998This day in weather historyWarnings in Iowa, August 1998

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: 5657407, 5657408, 5657406, 5657404, 5657405.