Alert archive / Iowa / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 33, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Apr 25, 1998, 7:07 PM CDT for Sac County, Iowa. It was in force for 33 min. 2 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
- Apr 25, 1998, 7:07 PM CDT (00:07 UTC)
- Expired
- Apr 25, 1998, 7:40 PM CDT
- In force
- 33 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
County Sac County, IA
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Apr 25, 7:14 PM CDT | Hail 0.75 | Wall Lake, IA | |
| Apr 25, 7:15 PM CDT | Hail 1.5 | Wall Lake, 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 watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Apr 25, 6:30 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
The nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 0.1 hours before the alert went out and 158 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 892 m above ground
- 0-6 km bulk shear
- 4 kt
- 0-1 km storm-relative helicity
- 16 m²/s²
- 0-3 km storm-relative helicity
- 98 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
402 WUUS1 KDSM 260008 RRA SVRDSM IAC161-260040- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE DES MOINES IA 707 PM CDT SAT APR 25 1998 THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... SOUTHERN SAC COUNTY IN WEST CENTRAL IOWA * UNTIL 740 PM CDT * AT 706 PM CDT... DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 53 MILES WEST SOUTHWEST OF FORT DODGE OR 4 MILES SOUTHEAST OF ODEBOLT MOVING NORTH AT 25 MPH. * THIS STORM CAN BE EXPECTED NEAR... LAKE VIEW BY 702 PM CDT ODEBOLT BY 706 PM CDT EARLY BY 727 PM CDT THIS IS A DANGEROUS STORM STAY INDOORS AWAY FROM WINDOWS. SMITH
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, Apr 25, 1:45 PM CDT, 5 hours 22 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086- 092>097-261100- CENTRAL IOWA THUNDERSTORM OUTLOOK...UPDATE NATIONAL WEATHER SERVICE DES MOINES IA 145 PM CDT SAT APR 25 1998 HAZARD--THUNDERSTORMS WITH LARGE HAIL AND DAMAGING WINDS. SOME STORMS COULD HAVE HEAVY RAIN. AREA OF CONCERN--THUNDERSTORMS ARE POSSIBLE ACROSS ALL OF CENTRAL IOWA BUT THE LIKELIHOOD OF SEVERE WEATHER WILL PRIMARILY BE SOUTH OF HIGHWAY 92 AND WEST OF HIGHWAY 169. TIMING--THUNDERSTORMS WILL REDEVELOP AFTER 4 PM BUT THE BEST TIME FOR SEVERE WEATHER WILL BE BETWEEN 5 TO 10 PM. METEOROLOGICAL COMMENTS--LOW PRESSURE OVER THE EASTERN KANSAS/NEBRASKA BORDER IS CONTINUING TO CREEP EAST. SUFFICIENT HEATING IS OCCURRING OVER SOUTHWEST IOWA AS MOISTURE CONTINUES TO STREAM NORTHWARD. THE MOISTURE IS IN A FAIRLY NARROW BAND ALONG AND NORTH OF A SURFACE WARM FRONT STRETCHED ACROSS NORTHERN MISSOURI. AS COLDER AIR WRAPS AROUND AROUND THE LOW AT 700 MB THE THREAT FOR SEVERE THUNDERSTORMS WILL INCREASE. AT THIS TIME IT APPEARS THE BEST TIME FOR SEVERE WEATHER WILL BE DURING THE EARLY EVENING HOURS. PRECAUTIONS--EMERGENCY MANAGERS MAY WANT TO ALERT THEIR COUNTY SPOTTERS TO THE LIKELIHOOD OF THUNDERSTORMS FOR THE AFTERNOON AND THE POSSIBILITY SEVERE STORMS AFTER 5 PM. THE BEST CHANCE FOR SEVERE WEATHER WILL BE ALONG AND SOUTH OF HIGHWAY 92 AND WEST OF HIGHWAY 169. KEEP AN EYE TO THE SKY FOR THE DEVELOPMENT OF THUNDERSTORMS THIS AFTERNOON AND BE PREPARED TO ACT QUICKLY. FAB
Special weather statement, Apr 25, 4:00 PM CDT, 3 hours 7 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086- 092>097-261100- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 400 PM CDT SAT APR 25 1998 HAZARD--THUNDERSTORMS WITH LARGE HAIL AND DAMAGING WINDS. AREA OF CONCERN--THUNDERSTORMS ARE POSSIBLE ACROSS ALL OF CENTRAL IOWA BUT THE LIKELIHOOD OF SEVERE WEATHER WILL PRIMARILY BE SOUTH OF HIGHWAY 92 AND WEST OF HIGHWAY 169. TIMING--THUNDERSTORMS WILL REDEVELOP AFTER 5 PM BUT THE BEST TIME FOR SEVERE WEATHER WILL BE BETWEEN 6 TO 9 PM. METEOROLOGICAL COMMENTS--LOW PRESSURE OVER THE EASTERN KANSAS/NEBRASKA BORDER IS CONTINUING TO CREEP EAST. A CAP AT 700 MB IS PREVENTING CONVECTION FROM STARTING HOWEVER THIS CAP IS EXPECTED TO ERODE AWAY AS COLDER AIR ALOFT WRAPS INTO THE LOW IN EASTERN NEBRASKA. THE CAP IS EXPECTED TO BREAK EARLY THIS EVENING AND IF IT DOES...THUNDERSTORMS WILL ERUPT. THESE STORMS HAVE THE POTENTIAL FOR LARGE HAIL AND DAMAGING WIND. AT THIS TIME ONLY A COUPLE THUNDERSTORMS ARE BEING PICKED UP BY RADAR BUT THEY ARE WEAK. WIDESPREAD THUNDERSTORM DEVELOPMENT IS NOT EXPECTED UNTIL AFTER 5 PM WITH THE POTENTIAL FOR SEVERE STORMS AFTER 6 PM. PRECAUTIONS--EMERGENCY MANAGERS MAY WANT TO ALERT THEIR COUNTY SPOTTERS TO THE LIKELIHOOD OF THUNDERSTORMS FOR THE AFTERNOON AND THE POSSIBILITY SEVERE STORMS AFTER 5 PM. THE BEST CHANCE FOR SEVERE WEATHER WILL BE ALONG AND SOUTH OF HIGHWAY 92 AND WEST OF HIGHWAY 169. KEEP AN EYE TO THE SKY FOR THE DEVELOPMENT OF THUNDERSTORMS THIS AFTERNOON AND BE PREPARED TO ACT QUICKLY. FAB
Special weather statement, Apr 25, 4:00 PM CDT, 3 hours 7 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086- 092>097-261100- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 400 PM CDT SAT APR 25 1998 HAZARD--THUNDERSTORMS WITH LARGE HAIL AND DAMAGING WINDS. AREA OF CONCERN--THUNDERSTORMS ARE POSSIBLE ACROSS ALL OF CENTRAL IOWA BUT THE LIKELIHOOD OF SEVERE WEATHER WILL PRIMARILY BE SOUTH OF HIGHWAY 92 AND WEST OF HIGHWAY 169. TIMING--THUNDERSTORMS WILL REDEVELOP AFTER 5 PM BUT THE BEST TIME FOR SEVERE WEATHER WILL BE BETWEEN 6 TO 9 PM. METEOROLOGICAL COMMENTS--LOW PRESSURE OVER THE EASTERN KANSAS/NEBRASKA BORDER IS CONTINUING TO CREEP EAST. A CAP AT 700 MB IS PREVENTING CONVECTION FROM STARTING HOWEVER THIS CAP IS EXPECTED TO ERODE AWAY AS COLDER AIR ALOFT WRAPS INTO THE LOW IN EASTERN NEBRASKA. THE CAP IS EXPECTED TO BREAK EARLY THIS EVENING AND IF IT DOES...THUNDERSTORMS WILL ERUPT. THESE STORMS HAVE THE POTENTIAL FOR LARGE HAIL AND DAMAGING WIND. AT THIS TIME ONLY A COUPLE THUNDERSTORMS ARE BEING PICKED UP BY RADAR BUT THEY ARE WEAK. WIDESPREAD THUNDERSTORM DEVELOPMENT IS NOT EXPECTED UNTIL AFTER 5 PM WITH THE POTENTIAL FOR SEVERE STORMS AFTER 6 PM. PRECAUTIONS--EMERGENCY MANAGERS MAY WANT TO ALERT THEIR COUNTY SPOTTERS TO THE LIKELIHOOD OF THUNDERSTORMS FOR THE AFTERNOON AND THE POSSIBILITY SEVERE STORMS AFTER 5 PM. THE BEST CHANCE FOR SEVERE WEATHER WILL BE ALONG AND SOUTH OF HIGHWAY 92 AND WEST OF HIGHWAY 169. KEEP AN EYE TO THE SKY FOR THE DEVELOPMENT OF THUNDERSTORMS THIS AFTERNOON AND BE PREPARED TO ACT QUICKLY. FAB
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 25, 7:26 PM CDT | Severe Thunderstorm Warning | DMX | Greene | 34 min |
| Apr 25, 7:39 PM CDT | Severe Thunderstorm Warning | DMX | Calhoun | 36 min |
| Apr 25, 7:42 PM CDT | Severe Thunderstorm Warning | DMX | Sac | 33 min |
| Apr 25, 8:10 PM CDT | Severe Thunderstorm Warning | DMX | Greene, Webster | 35 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.