Alert archive / Iowa / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 137, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at May 28, 1998, 8:57 PM CDT for Calhoun County, Webster County, Iowa. It was in force for 33 min. 1 report 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 28, 1998, 8:57 PM CDT (01:57 UTC)
- Expired
- May 28, 1998, 9:30 PM CDT
- In force
- 33 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
Counties Calhoun County, IA, Webster County, IA
The radar
The Des Moines radar (KDMX), 94 km from the middle of the area, began a volume at 01:57 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 28, 9:26 PM CDT | Hail 1 | Lanyon, 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 |
|---|---|---|---|
| May 28, 4:00 PM CDT | Tornado Watch | SPC | 5 hr |
| May 28, 8:45 PM CDT | Tornado Watch | SPC | 6 hr |
The nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 2.0 hours before the alert went out and 202 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
- 2835 J/kg
- Mixed-layer CIN
- -9 J/kg
- Mixed-layer LCL
- 1954 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km storm-relative helicity
- 64 m²/s²
- 0-3 km storm-relative helicity
- 115 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 7.5
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KDSM 290157 RRA SVRDSM IAC025-187-290230- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE DES MOINES IA 857 PM CDT THU MAY 28 1998 THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... EASTERN CALHOUN COUNTY IN WEST CENTRAL IOWA WESTERN WEBSTER COUNTY IN CENTRAL IOWA * UNTIL 930 PM CDT * AT 855 PM CDT... DOPPLER RADAR INDICATED A LINE OF SEVERE THUNDERSTORMS 16 MILES WEST SOUTHWEST OF FORT DODGE OR 7 MILES NORTH NORTHWEST OF FARNHAMVILLE MOVING EAST AT 25 MPH. * THIS STORM CAN BE EXPECTED NEAR... FARNHAMVILLE BY 900 PM CDT BARNUM BY 900 PM CDT CALLENDER BY 909 PM CDT MOORLAND BY 909 PM CDT GOWRIE BY 909 PM CDT THIS IS A DANGEROUS STORM WITH QUARTER SIZE HAIL AND WIND GUSTS OVER 60 MPH! STAY INDOORS AWAY FROM WINDOWS. A TORNADO WATCH IS ALSO IN EFFECT. TORNADOES HAVE OCCURRED ALREADY THISz EVENING AND MAY DO SO AGAIN AT ANY TIME. PYTLAK
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 28, 7:49 PM CDT, 1 hour 8 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086- 092>097-291100- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 749 PM CDT THU MAY 28 1998 HAZARD--SCATTERED THUNDERSTORMS...SOME POSSIBLY SEVERE AND CAPABLE OF PRODUCING ISOLATED TORNADOES...LARGE HAIL AND DAMAGING WINDS. LOCALLY HEAVY RAINFALL IS ALSO POSSIBLE WITH SOME AREAS SEEING BETWEEN 1 AND 3 INCHES OF RAIN IN A SHORT TIME. AREAS OF CONCERN AND TIMING DETAILS--THROUGH 9 PM THE THREAT OF SEVERE WEATHER WILL BE OVER THE NORTHERN HALF OF IOWA...MAINLY ALONG AND NORTH OF HIGHWAY 20. AFTER 9 PM THE THREAT OF SEVERE WEATHER WILL SHIFT INTO AREAS FARTHER SOUTH...MAINLY SOUTH OF HIGHWAY 20 AND NORTH OF HIGHWAY 92. ADDITIONAL WATCHES MAY BE ISSUED IN IOWA THIS EVENING. METEOROLOGICAL COMMENTS--A COLD FRONT REMAINS ACROSS THE NORTHERN THIRD OF IOWA THIS EVENING. MOISTURE CONTINUES TO POOL ALONG THIS BOUNDARY WITH DEW POINTS IN THE MID 60S TO LOWER 70S ACROSS THE STATE. THE ATMOSPHERE REMAINS VERY UNSTABLE WITH LIFTED INDICES IN THE -6 TO -10 RANGE. THIS INSTABILITY INDICATES THE POTENTIAL FOR ISOLATED TORNADOES AND SEVERE STORMS. THE FIRST ROUND OF STORMS THAT DEVELOPED ALONG THE FRONTAL BOUNDARY LATE THIS AFTERNOON PRODUCED AN OUTFLOW BOUNDARY THAT MOVED SOUTH INTO CENTRAL IOWA AND EXTENDS BACK INTO NORTHWEST IOWA WHERE ADDITIONAL THUNDERSTORMS HAVE DEVELOPED. SCATTERED THUNDERSTORMS WILL CONTINUE TO DEVELOP ALONG THIS BOUNDARY TONIGHT. PRECAUTIONS--EMERGENCY MANAGERS AND SPOTTERS SHOULD CONTINUE TO MONITOR THE WEATHER SITUATION THIS EVENING. DEPLOYMENT OF SPOTTERS IN CENTRAL IOWA MAY BE NEEDED AFTER 9 PM OR SO. CONDITIONS REMAIN FAVORABLE THIS EVENING FOR SEVERE THUNDERSTORMS AND VERY HEAVY RAINFALL. STARK
Special weather statement, May 28, 7:49 PM CDT, 1 hour 8 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086- 092>097-291100- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 749 PM CDT THU MAY 28 1998 HAZARD--SCATTERED THUNDERSTORMS...SOME POSSIBLY SEVERE AND CAPABLE OF PRODUCING ISOLATED TORNADOES...LARGE HAIL AND DAMAGING WINDS. LOCALLY HEAVY RAINFALL IS ALSO POSSIBLE WITH SOME AREAS SEEING BETWEEN 1 AND 3 INCHES OF RAIN IN A SHORT TIME. AREAS OF CONCERN AND TIMING DETAILS--THROUGH 9 PM THE THREAT OF SEVERE WEATHER WILL BE OVER THE NORTHERN HALF OF IOWA...MAINLY ALONG AND NORTH OF HIGHWAY 20. AFTER 9 PM THE THREAT OF SEVERE WEATHER WILL SHIFT INTO AREAS FARTHER SOUTH...MAINLY SOUTH OF HIGHWAY 20 AND NORTH OF HIGHWAY 92. ADDITIONAL WATCHES MAY BE ISSUED IN IOWA THIS EVENING. METEOROLOGICAL COMMENTS--A COLD FRONT REMAINS ACROSS THE NORTHERN THIRD OF IOWA THIS EVENING. MOISTURE CONTINUES TO POOL ALONG THIS BOUNDARY WITH DEW POINTS IN THE MID 60S TO LOWER 70S ACROSS THE STATE. THE ATMOSPHERE REMAINS VERY UNSTABLE WITH LIFTED INDICES IN THE -6 TO -10 RANGE. THIS INSTABILITY INDICATES THE POTENTIAL FOR ISOLATED TORNADOES AND SEVERE STORMS. THE FIRST ROUND OF STORMS THAT DEVELOPED ALONG THE FRONTAL BOUNDARY LATE THIS AFTERNOON PRODUCED AN OUTFLOW BOUNDARY THAT MOVED SOUTH INTO CENTRAL IOWA AND EXTENDS BACK INTO NORTHWEST IOWA WHERE ADDITIONAL THUNDERSTORMS HAVE DEVELOPED. SCATTERED THUNDERSTORMS WILL CONTINUE TO DEVELOP ALONG THIS BOUNDARY TONIGHT. PRECAUTIONS--EMERGENCY MANAGERS AND SPOTTERS SHOULD CONTINUE TO MONITOR THE WEATHER SITUATION THIS EVENING. DEPLOYMENT OF SPOTTERS IN CENTRAL IOWA MAY BE NEEDED AFTER 9 PM OR SO. CONDITIONS REMAIN FAVORABLE THIS EVENING FOR SEVERE THUNDERSTORMS AND VERY HEAVY RAINFALL. STARK
Local storm report, May 28, 8:39 PM CDT, 18 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
839 PM CDT THU MAY 28 1998
TIME(CDT) .....CITY LOCATION..... STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0340 PM POCAHONTAS IA TORNADO
05/28/98 POCAHONTAS TORNADO 6 MILES NORTHWEST
OF POCAHANTAS
0523 PM RADCLIFFE IA WIND DAMAGE
05/28/98 HARDIN SHINGLES BLOWN OFF ROOF
0542 PM GRUNDY CENTER IA 70 MPH TSTM GUST
05/28/98 GRUNDY JUST NORTH OF GRUNDY
CENTER
0553 PM BADGER IA 1.75 INCH HAIL
05/28/98 WEBSTERThe office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 28, 8:20 PM CDT | Severe Thunderstorm Warning | DMX | Sac | 20 min |
| May 28, 8:24 PM CDT | Severe Thunderstorm Warning | DMX | Calhoun | 36 min |
| May 28, 9:22 PM CDT | Tornado Warning | DMX | Crawford | 33 min |
| May 28, 9:29 PM CDT | Severe Thunderstorm Warning | DMX | Webster | 36 min |
| May 28, 9:41 PM CDT | Severe Thunderstorm Warning | DMX | Boone | 34 min |
| May 28, 9:52 PM CDT | Tornado Warning | DMX | Crawford | 33 min |
| May 28, 10:15 PM CDT | Severe Thunderstorm Warning | DMX | Story | 50 min |
| May 28, 10:21 PM CDT | Tornado Warning | DMX | Carroll, Crawford | 39 min |
| May 28, 10:21 PM CDT | Tornado Warning | DMX | Carroll, Crawford | 34 min |
| May 28, 10:40 PM CDT | Severe Thunderstorm Warning | DMX | Marshall | 50 min |
| May 28, 10:46 PM CDT | Severe Thunderstorm Warning | DMX | Crawford | 34 min |
| May 28, 10:50 PM CDT | Severe Thunderstorm Warning | DMX | Carroll | 35 min |
| May 28, 11:04 PM CDT | Tornado Warning | DMX | Carroll | 36 min |
| May 28, 11:10 PM CDT | Tornado Warning | DMX | Audubon | 35 min |
| May 28, 11:25 PM CDT | Tornado Warning | DMX | Greene, Guthrie | 35 min |
| May 28, 11:44 PM CDT | Tornado Warning | DMX | Audubon, Guthrie | 36 min |
| May 28, 11:59 PM CDT | Tornado Warning | DMX | Dallas, Guthrie | 51 min |
| May 29, 12:09 AM CDT | Severe Thunderstorm Warning | DMX | Audubon | 36 min |
| May 29, 12:24 AM CDT | Tornado Warning | DMX | Guthrie | 26 min |
| May 29, 12:33 AM CDT | Severe Thunderstorm Warning | DMX | Cass | 32 min |
| May 29, 12:50 AM CDT | Severe Thunderstorm Warning | DMX | Adair, Dallas, Guthrie | 50 min |
| May 29, 1:24 AM CDT | Severe Thunderstorm Warning | DMX | Cass | 31 min |
| May 29, 2:01 AM CDT | Severe Thunderstorm Warning | DMX | Adams | 34 min |
| May 29, 2:01 AM CDT | Severe Thunderstorm Warning | DMX | Adams | 39 min |
| May 29, 2:21 AM CDT | Severe Thunderstorm Warning | DMX | Adair, Union | 49 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; radar from the NEXRAD Level II archive.