Alert archive / Iowa / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 101, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at May 21, 1998, 10:04 PM CDT for Dallas County, Madison County, Iowa. It was in force for 41 min. 4 reports came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- May 21, 1998, 10:04 PM CDT (03:04 UTC)
- Expired
- May 21, 1998, 10:45 PM CDT
- In force
- 41 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
Counties Dallas County, IA, Madison County, IA
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 21, 10:30 PM CDT | Thunderstorm Wind 61 | Macksburg, IA | |
| May 21, 10:30 PM CDT | Thunderstorm Wind 50 | Truro, IA | |
| May 21, 10:35 PM CDT | Thunderstorm Wind 52 | Adel, IA | |
| May 21, 10:40 PM CDT | Thunderstorm Wind 50 | Truro, IA |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.
The nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 3.1 hours before the alert went out and 196 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
- 66 J/kg
- Mixed-layer CIN
- -295 J/kg
- Mixed-layer LCL
- 905 m above ground
- 0-6 km bulk shear
- 59 kt
- 0-1 km storm-relative helicity
- 300 m²/s²
- 0-3 km storm-relative helicity
- 484 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 7.6
The text
As transmitted, in the capitals the NWS used until 2016.
909 WUUS1 KDSM 220304 RRA SVRDSM IAC049-121-220345- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE DES MOINES IA 1004 PM CDT THU MAY 21 1998 THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... SOUTHERN DALLAS COUNTY IN CENTRAL IOWA MADISON COUNTY IN SOUTH CENTRAL IOWA * UNTIL 1045 PM CDT * AT 959 PM CDT... DOPPLER RADAR INDICATED A LINE OF SEVERE THUNDERSTORMS 40 MILES SOUTHWEST OF DES MOINES OR 10 MILES WEST OF WINTERSET MOVING EAST AT 40 MPH. * THIS STORM CAN BE EXPECTED NEAR... MACKSBURG BY 1015 PM CDT WINTERSET BY 1020 PM CDT ADEL BY 1025 PM CDT WAUKEE BY 1035 PM CDT DAMAGING WINDS ARE OCCURRING WITH THIS STORM. GO INSIDE A STURDY BUILDING AND STAY AWAY FROM WINDOWS JUNGBLUTH
What forecasters said that day
The local office's own words before this severe thunderstorm 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, May 21, 7:16 PM CDT, 2 hours 48 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 716 PM CDT THU MAY 21 1998 HAZARD--SCATTERED THUNDERSTORMS CAPABLE OF PRODUCING HEAVY RAIN...STRONG WIND GUSTS AND LARGE HAIL. TIMING DETAILS AND AREA OF CONCERN--THE WESTERN QUARTER OF IOWA THROUGH 10 PM AND THE SOUTHERN TWO TIERS OF IOWA COUNTIES FROM 10 PM TO MIDNIGHT. AN ADDITIONAL THREAT FOR REDEVELOPMENT OF STORMS TOWARDS DAYBREAK. METEOROLOGICAL COMMENTS-- THUNDERSTORMS HAVE DEVELOPED ALONG A BOUNDARY OVER NORTHEASTERN NEBRASKA DURING THE LATE AFTERNOON HOURS. THESE STORMS WILL BE MOVING INTO FAR WESTERN IOWA BY 8 PM AND THEN ACROSS THE WESTERN QUARTER OF THE WARNING AREA BEFORE HEADING TO THE SOUTHEAST. THE STORMS WILL COVER A CORRIDOR FROM ABOUT STORM LAKE TO DENISON...MOVING EAST TO ROUGHLY WEBSTER CITY THEN HEAD SOUTHEAST TOWARDS CHARITON AND OTTUMWA LATER THIS EVENING. THESE STORMS HAD A HISTORY OF PRODUCING STRONG WIND AND LARGE HAIL IN NEBRASKA BUT THEY ARE MOVING INTO A LESS FAVORABLE ENVIRONMENT AS THEY CROSS THE MISSOURI RIVER. THE MAIN THREAT FROM THESE STORMS WILL BE HEAVY RAIN WITH LOCAL AREAS EXPERIENCING STRONG WIND GUSTS AND HAIL. A SECONDARY COMPLEX OF STORMS OVER CENTRAL NEBRASKA WILL MAKE ITS WAY INTO IOWA OVERNIGHT AND ESSENTIALLY MOVE OVER THE SAME AREA WITH THE MAIN THREAT ONCE AGAIN BEING HEAVY RAIN. PRECAUTIONS--EMERGENCY MANAGERS...ESPECIALLY OVER SOUTHWEST IOWA... NEED TO BE ON THE ALERT FOR THE THREAT OF ADDITIONAL HEAVY RAINFALL TONIGHT AND AGAIN TOWARDS DAYBREAK ON FRIDAY. FAB
Special weather statement, May 21, 7:16 PM CDT, 2 hours 48 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 716 PM CDT THU MAY 21 1998 HAZARD--SCATTERED THUNDERSTORMS CAPABLE OF PRODUCING HEAVY RAIN...STRONG WIND GUSTS AND LARGE HAIL. TIMING DETAILS AND AREA OF CONCERN--THE WESTERN QUARTER OF IOWA THROUGH 10 PM AND THE SOUTHERN TWO TIERS OF IOWA COUNTIES FROM 10 PM TO MIDNIGHT. AN ADDITIONAL THREAT FOR REDEVELOPMENT OF STORMS TOWARDS DAYBREAK. METEOROLOGICAL COMMENTS-- THUNDERSTORMS HAVE DEVELOPED ALONG A BOUNDARY OVER NORTHEASTERN NEBRASKA DURING THE LATE AFTERNOON HOURS. THESE STORMS WILL BE MOVING INTO FAR WESTERN IOWA BY 8 PM AND THEN ACROSS THE WESTERN QUARTER OF THE WARNING AREA BEFORE HEADING TO THE SOUTHEAST. THE STORMS WILL COVER A CORRIDOR FROM ABOUT STORM LAKE TO DENISON...MOVING EAST TO ROUGHLY WEBSTER CITY THEN HEAD SOUTHEAST TOWARDS CHARITON AND OTTUMWA LATER THIS EVENING. THESE STORMS HAD A HISTORY OF PRODUCING STRONG WIND AND LARGE HAIL IN NEBRASKA BUT THEY ARE MOVING INTO A LESS FAVORABLE ENVIRONMENT AS THEY CROSS THE MISSOURI RIVER. THE MAIN THREAT FROM THESE STORMS WILL BE HEAVY RAIN WITH LOCAL AREAS EXPERIENCING STRONG WIND GUSTS AND HAIL. A SECONDARY COMPLEX OF STORMS OVER CENTRAL NEBRASKA WILL MAKE ITS WAY INTO IOWA OVERNIGHT AND ESSENTIALLY MOVE OVER THE SAME AREA WITH THE MAIN THREAT ONCE AGAIN BEING HEAVY RAIN. PRECAUTIONS--EMERGENCY MANAGERS...ESPECIALLY OVER SOUTHWEST IOWA... NEED TO BE ON THE ALERT FOR THE THREAT OF ADDITIONAL HEAVY RAINFALL TONIGHT AND AGAIN TOWARDS DAYBREAK ON FRIDAY. FAB
Special weather statement, May 21, 7:17 PM CDT, 2 hours 47 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 717 PM CDT THU MAY 21 1998 HAZARD--SCATTERED THUNDERSTORMS CAPABLE OF PRODUCING HEAVY RAIN...STRONG WIND GUSTS AND LARGE HAIL. TIMING DETAILS AND AREA OF CONCERN--THE WESTERN QUARTER OF IOWA THROUGH 10 PM AND THE SOUTHERN TWO TIERS OF IOWA COUNTIES FROM 10 PM TO MIDNIGHT. THERE IS ALSO AN ADDITIONAL THREAT FOR REDEVELOPMENT OF STORMS TOWARDS DAYBREAK. METEOROLOGICAL COMMENTS-- THUNDERSTORMS HAVE DEVELOPED ALONG A BOUNDARY OVER NORTHEASTERN NEBRASKA DURING THE LATE AFTERNOON HOURS. THESE STORMS WILL BE MOVING INTO FAR WESTERN IOWA BY 8 PM AND THEN ACROSS THE WESTERN QUARTER OF THE WARNING AREA BEFORE HEADING TO THE SOUTHEAST. THE STORMS WILL COVER A CORRIDOR FROM ABOUT STORM LAKE TO DENISON...MOVING EAST TO ROUGHLY WEBSTER CITY THEN HEAD SOUTHEAST TOWARDS CHARITON AND OTTUMWA LATER THIS EVENING. THESE STORMS HAD A HISTORY OF PRODUCING STRONG WIND AND LARGE HAIL IN NEBRASKA BUT THEY ARE MOVING INTO A LESS FAVORABLE ENVIRONMENT AS THEY CROSS THE MISSOURI RIVER. THE MAIN THREAT FROM THESE STORMS WILL BE HEAVY RAIN WITH LOCAL AREAS EXPERIENCING STRONG WIND GUSTS AND HAIL. A SECONDARY COMPLEX OF STORMS OVER CENTRAL NEBRASKA WILL MAKE ITS WAY INTO IOWA OVERNIGHT AND ESSENTIALLY MOVE OVER THE SAME AREA WITH THE MAIN THREAT ONCE AGAIN BEING HEAVY RAIN. PRECAUTIONS--EMERGENCY MANAGERS...ESPECIALLY OVER SOUTHWEST IOWA... NEED TO BE ON THE ALERT FOR THE THREAT OF ADDITIONAL HEAVY RAINFALL TONIGHT AND AGAIN TOWARDS DAYBREAK ON FRIDAY. FAB
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 21, 8:54 PM CDT | Severe Thunderstorm Warning | DMX | Audubon, Cass | 31 min |
| May 21, 9:29 PM CDT | Severe Thunderstorm Warning | DMX | Adair, Guthrie | 31 min |
| May 21, 10:13 PM CDT | Severe Thunderstorm Warning | DMX | Union | 47 min |
| May 21, 10:32 PM CDT | Severe Thunderstorm Warning | DMX | Clarke | 48 min |
| May 21, 10:45 PM CDT | Severe Thunderstorm Warning | DMX | Warren | 50 min |
| May 21, 11:01 PM CDT | Severe Thunderstorm Warning | DMX | Decatur | 44 min |
| May 21, 11:03 PM CDT | Severe Thunderstorm Warning | DMX | Lucas | 47 min |
| May 21, 11:17 PM CDT | Severe Thunderstorm Warning | DMX | Wayne | 48 min |
| May 21, 11:26 PM CDT | Severe Thunderstorm Warning | DMX | Marion | 49 min |
| May 21, 11:51 PM CDT | Severe Thunderstorm Warning | DMX | Appanoose, Monroe | 49 min |
| May 22, 12:27 AM CDT | Severe Thunderstorm Warning | DMX | Davis | 48 min |
| May 22, 1:53 AM CDT | Severe Thunderstorm Warning | DMX | Adair | 32 min |
| May 22, 2:15 AM CDT | Severe Thunderstorm Warning | DMX | Madison | 45 min |
Nearby
Severe Thunderstorm Warnings in Iowa, 1998Every severe thunderstorm 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.