Alert archive / Iowa / Flash Flood Warnings in 1998
Flash Flood Warning 31, NWS Des Moines, IA
NWS Des Moines, IA issued this flash flood warning at Jul 22, 1998, 12:21 AM CDT for Cass County, Iowa. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Jul 22, 1998, 12:21 AM CDT (05:21 UTC)
- Expired
- Jul 22, 1998, 3:00 AM CDT
- In force
- 3 hr
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
County Cass County, IA
The nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 5.4 hours before the alert went out and 120 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 1959 J/kg
- Mixed-layer CIN
- -218 J/kg
- Mixed-layer LCL
- 991 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 111 m²/s²
- 0-3 km storm-relative helicity
- 350 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 15.9
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KDSM 220521 FFWDSM IAC029-220800- BULLETIN - EAS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE DES MOINES IA 1221 AM CDT WED JUL 22 1998 THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A * FLASH FLOOD WARNING FOR... CASS COUNTY IN SOUTHWESTERN IOWA * UNTIL 300 AM CDT * AT 1220 AM CDT... AREA LAW ENFORCEMENT INDICATED A THUNDERSTORM WITH VERY HEAVY RAIN ALONG AND JUST SOUTH OF INTERSTATE 80... MOVING SOUTH AT LESS THAN 5 MPH. * UP TO 5 INCHES OF RAIN IS EXPECTED...ESPEICALLY IN THE NORTH END OF THE COUNTY. THIS WILL CAUSE RAPID RISES ALONG TRIBUTARIES OF THE NISHNABOTNA RIVER. SOME STREAMS AFFECTED INCLUDE... CAMP CREEK BUCK CREEK TROUBLESOME CREEK T*URKEY CREEK BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE DANGER OF FLOODING. PYTLAK
What forecasters said that day
The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
In the hours before
Special weather statement, Jul 21, 10:50 PM CDT, 1 hour 31 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086- 092>097-221100- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 1050 PM CDT TUE JUL 21 1998 HAZARD--THUNDERSTORMS PRODUCING HEAVY RAIN AND SMALL HAIL. 3 TO 5 INCHES OF RAIN CAN BE EXPECTED OVERNIGHT. THERE IS A SMALL THREAT FOR LOCALIZED DAMAGING WIND. TIMING--BETWEEN 1040 PM AND 6 AM. AREA OF CONCERN--HEAVY RAIN PRODUCING THUNDERSTORMS WILL MOVE ALONG AND SOUTH OF INTERSTATE 80. 3 TO 5 INCHES OF RAIN WILL FALL OVERNIGHT. A STORM OR TWO COULD PRODUCE HAIL TO ONE INCH BUT THE GREATER THREAT WILL BE THE TORRENTIAL RAIN AND DANGEROUS LIGHTNING. METEOROLOGICAL COMMENTS--THUNDERSTORMS ARE RAPIDLY DEVELOPING ALONG A STALLED FRONTAL BOUNDARY IN CENTRAL IOWA. PRECIPITABLE WATER AMOUNTS IN EXCESS OF TWO INCHES ARE POOLING ALONG THIS BOUNDARY. STORMS WILL TRAIN ALONG THIS BOUNDARY THROUGH MUCH OF THE NIGHT CAUSING LONG DURATIONS OF HEAVY RAIN. A FLASH FLOOD WATCH MAY BE NEEDED FOR COUNTIES ALONG AND SOUTH OF INTERSTATE 80 BECAUSE OF THE HEAVY RAIN POTENTIAL. PRECAUTIONS--IF RIVERS RISE RAPIDLY MOVE TO HIGHER GROUND IMMEDIATELY. DO NOT ATTEMPT TO CROSS FLOODED ROADWAYS. EMERGENCY MANAGERS SHOULD MONITOR RIVER LEVELS IN THEIR COUNTIES. FAB
Special weather statement, Jul 21, 10:50 PM CDT, 1 hour 31 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086- 092>097-221100- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 1050 PM CDT TUE JUL 21 1998 HAZARD--THUNDERSTORMS PRODUCING HEAVY RAIN AND SMALL HAIL. 3 TO 5 INCHES OF RAIN CAN BE EXPECTED OVERNIGHT. THERE IS A SMALL THREAT FOR LOCALIZED DAMAGING WIND. TIMING--BETWEEN 1040 PM AND 6 AM. AREA OF CONCERN--HEAVY RAIN PRODUCING THUNDERSTORMS WILL MOVE ALONG AND SOUTH OF INTERSTATE 80. 3 TO 5 INCHES OF RAIN WILL FALL OVERNIGHT. A STORM OR TWO COULD PRODUCE HAIL TO ONE INCH BUT THE GREATER THREAT WILL BE THE TORRENTIAL RAIN AND DANGEROUS LIGHTNING. METEOROLOGICAL COMMENTS--THUNDERSTORMS ARE RAPIDLY DEVELOPING ALONG A STALLED FRONTAL BOUNDARY IN CENTRAL IOWA. PRECIPITABLE WATER AMOUNTS IN EXCESS OF TWO INCHES ARE POOLING ALONG THIS BOUNDARY. STORMS WILL TRAIN ALONG THIS BOUNDARY THROUGH MUCH OF THE NIGHT CAUSING LONG DURATIONS OF HEAVY RAIN. A FLASH FLOOD WATCH MAY BE NEEDED FOR COUNTIES ALONG AND SOUTH OF INTERSTATE 80 BECAUSE OF THE HEAVY RAIN POTENTIAL. PRECAUTIONS--IF RIVERS RISE RAPIDLY MOVE TO HIGHER GROUND IMMEDIATELY. DO NOT ATTEMPT TO CROSS FLOODED ROADWAYS. EMERGENCY MANAGERS SHOULD MONITOR RIVER LEVELS IN THEIR COUNTIES. FAB
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 21, 10:44 PM CDT | Severe Thunderstorm Warning | DMX | Polk | 31 min |
Nearby
Flash Flood Warnings in Iowa, 1998Every flash flood warning in 1998
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive.