Alert archive / Iowa / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 273, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Jul 21, 1998, 7:26 AM CDT for Palo Alto County, Pocahontas County, Iowa. It was in force for 34 min. 3 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
- Jul 21, 1998, 7:26 AM CDT (12:26 UTC)
- Expired
- Jul 21, 1998, 8:00 AM CDT
- In force
- 34 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
Counties Palo Alto County, IA, Pocahontas County, IA
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 21, 7:37 AM CDT | Thunderstorm Wind 61 | Varina, IA | |
| Jul 21, 7:39 AM CDT | Thunderstorm Wind 52 | Pocahontas Muni Arpt, IA | |
| Jul 21, 7:45 AM CDT | Thunderstorm Wind 61 | Ayrshire, 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 |
|---|---|---|---|
| Jul 21, 6:15 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
The nearest sounding before it
Omaha, NE (KOAX), launched 12:00Z, 0.4 hours before the alert went out and 225 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
- 520 J/kg
- Mixed-layer CIN
- -388 J/kg
- Mixed-layer LCL
- 1700 m above ground
- 0-6 km bulk shear
- 17 kt
- 0-1 km storm-relative helicity
- -212 m²/s²
- 0-3 km storm-relative helicity
- -251 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.0
The text
As transmitted, in the capitals the NWS used until 2016.
307 WUUS1 KDSM 211227 RRA SVRDSM IAC147-151-211300- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE DES MOINES IA 726 AM CDT TUE JUL 21 1998 THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... PALO ALTO COUNTY IN NORTHWESTERN IOWA POCAHONTAS COUNTY IN NORTHWESTERN IOWA * UNTIL 800 AM CDT * AT 724 AM CDT... DOPPLER RADAR INDICATED A LINE OF SEVERE THUNDERSTORMS 13 MILES SOUTHEAST OF SPENCER OR 8 MILES WEST SOUTHWEST OF AYRSHIRE MOVING EAST AT 55 MPH. * THIS STORM CAN BE EXPECTED NEAR... AYRSHIRE BY 728 AM CDT HAVELOCK BY 731 AM CDT EMMETSBURG BY 740 AM CDT POCAHONTAS BY 740 AM CDT THIS STORM HAS A HISTORY OF DAMAGING WIND. GO INSIDE A STURDY BUILDING AND STAY AWAY FROM WINDOWS SEARCY
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, Jul 21, 5:33 AM CDT, 1 hour 53 minutes before
IAZ004>007-015>017-023>028-035>039-047>050-061-062-075-086-220000- CENTRAL IOWA THUNDERSTORM OUTLOOK...CORRECTED DATE IN MND HEADER NATIONAL WEATHER SERVICE DES MOINES IA 533 AM CDT TUE JUL 21 1998 HAZARD--SCATTERED THUNDERSTORMS WITH WIND GUSTS TO 60 MPH AND HEAVY RAINFALL. AREA OF CONCERN AND TIMING DETAILS--NORTHEAST OF A SAC CITY TO MASON CITY LINE ANYTIME TODAY. SOUTHEAST OF THIS LINE THIS EVENING INTO THE OVERNIGHT HOURS. METEOROLOGICAL COMMENTS--A COLD FRONT LOCATED FROM NORTHEAST NEBRASKA THROUGH NORTHWEST IOWA INTO SOUTHEASTERN MINNESOTA WILL CONTINUE TO MOVE SOUTHEAST TODAY. MEANWHILE...LOW LEVEL SOUTHERLY WINDS WILL CONTINUE TO TRANSPORT MOISTURE NORTHWARD INTO AND OVER THE FRONT. SCATTERED THUNDERSTORMS OVER SOUTHEAST SOUTH DAKOTA WILL CONTINUE TO MOVE EAST THIS MORNING INTO NORTHERN IOWA. SOME OF THESE STORMS COULD PRODUCE WIND GUSTS TO 60 MPH THIS MORNING. ADDITIONAL ACTIVITY COULD REDEVELOP LATER THIS AFTERNOON OVER THE OUTLOOK AREA AS WELL. DUE TO WARM TEMPERATURES ALOFT...ANY HAIL THAT OCCURS SHOULD REMAIN BELOW SEVERE CRITERIA...OR LESS THAN THREE-QUARTERS OF AN INCH IN DIAMETER. AS THE FRONT CONTINUES SOUTHWARD LATER THIS EVENING... ADDITIONAL SHOWERS AND THUNDERSTORMS WILL OVERSPREAD THE REST OF THE STATE WITH WIND GUSTS TO 60 MPH AND HEAVY RAIN THE PRIMARY THREAT. THE FRONT MAY STALL OUT OVER CENTRAL OR SOUTHERN IOWA OVERNIGHT... BRINGING REPEATED HEAVY RAINS TO THESE PORTIONS OF THE STATE. WITH THE RECENT HOT AND DRY WEATHER...FLOODING SHOULD NOT BE A CONCERN... THOUGH IF REPEATED HEAVY RAIN IS RECEIVED...SOME MINOR FLOODING COULD OCCUR. PRECAUTIONS -SPOTTERS MAY BE NEEDED OVER NORTHERN IOWA TODAY AND THE REST OF THE STATE TONIGHT. KEEP IN MIND THERE IS ALSO A HEAT ADVISORY OUT FOR ABOUT THE SOUTHERN HALF OF IOWA. IF YOU MUST BE OUTSIDE IN THESE AREAS...DRINK PLENTY OF WATER AND DON/T OVEREXERT YOURSELF. SEARCY
Special weather statement, Jul 21, 5:33 AM CDT, 1 hour 53 minutes before
IAZ004>007-015>017-023>028-035>039-047>050-061-062-075-086-220000- CENTRAL IOWA THUNDERSTORM OUTLOOK...CORRECTED DATE IN MND HEADER NATIONAL WEATHER SERVICE DES MOINES IA 533 AM CDT TUE JUL 21 1998 HAZARD--SCATTERED THUNDERSTORMS WITH WIND GUSTS TO 60 MPH AND HEAVY RAINFALL. AREA OF CONCERN AND TIMING DETAILS--NORTHEAST OF A SAC CITY TO MASON CITY LINE ANYTIME TODAY. SOUTHEAST OF THIS LINE THIS EVENING INTO THE OVERNIGHT HOURS. METEOROLOGICAL COMMENTS--A COLD FRONT LOCATED FROM NORTHEAST NEBRASKA THROUGH NORTHWEST IOWA INTO SOUTHEASTERN MINNESOTA WILL CONTINUE TO MOVE SOUTHEAST TODAY. MEANWHILE...LOW LEVEL SOUTHERLY WINDS WILL CONTINUE TO TRANSPORT MOISTURE NORTHWARD INTO AND OVER THE FRONT. SCATTERED THUNDERSTORMS OVER SOUTHEAST SOUTH DAKOTA WILL CONTINUE TO MOVE EAST THIS MORNING INTO NORTHERN IOWA. SOME OF THESE STORMS COULD PRODUCE WIND GUSTS TO 60 MPH THIS MORNING. ADDITIONAL ACTIVITY COULD REDEVELOP LATER THIS AFTERNOON OVER THE OUTLOOK AREA AS WELL. DUE TO WARM TEMPERATURES ALOFT...ANY HAIL THAT OCCURS SHOULD REMAIN BELOW SEVERE CRITERIA...OR LESS THAN THREE-QUARTERS OF AN INCH IN DIAMETER. AS THE FRONT CONTINUES SOUTHWARD LATER THIS EVENING... ADDITIONAL SHOWERS AND THUNDERSTORMS WILL OVERSPREAD THE REST OF THE STATE WITH WIND GUSTS TO 60 MPH AND HEAVY RAIN THE PRIMARY THREAT. THE FRONT MAY STALL OUT OVER CENTRAL OR SOUTHERN IOWA OVERNIGHT... BRINGING REPEATED HEAVY RAINS TO THESE PORTIONS OF THE STATE. WITH THE RECENT HOT AND DRY WEATHER...FLOODING SHOULD NOT BE A CONCERN... THOUGH IF REPEATED HEAVY RAIN IS RECEIVED...SOME MINOR FLOODING COULD OCCUR. PRECAUTIONS -SPOTTERS MAY BE NEEDED OVER NORTHERN IOWA TODAY AND THE REST OF THE STATE TONIGHT. KEEP IN MIND THERE IS ALSO A HEAT ADVISORY OUT FOR ABOUT THE SOUTHERN HALF OF IOWA. IF YOU MUST BE OUTSIDE IN THESE AREAS...DRINK PLENTY OF WATER AND DON/T OVEREXERT YOURSELF. SEARCY
Special weather statement, Jul 21, 5:34 AM CDT, 1 hour 52 minutes before
IAZ004>007-015>017-023>028-035>039-047>050-061-062-075-086-220000- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 533 AM CDT MON JUL 20 1998 HAZARD--SCATTERED THUNDERSTORMS WITH WIND GUSTS TO 60 MPH AND HEAVY RAINFALL. AREA OF CONCERN AND TIMING DETAILS--NORTHEAST OF A SAC CITY TO MASON CITY LINE ANYTIME TODAY. SOUTHEAST OF THIS LINE THIS EVENING INTO THE OVERNIGHT HOURS. METEOROLOGICAL COMMENTS--A COLD FRONT LOCATED FROM NORTHEAST NEBRASKA THROUGH NORTHWEST IOWA INTO SOUTHEASTERN MINNESOTA WILL CONTINUE TO MOVE SOUTHEAST TODAY. MEANWHILE...LOW LEVEL SOUTHERLY WINDS WILL CONTINUE TO TRANSPORT MOISTURE NORTHWARD INTO AND OVER THE FRONT. SCATTERED THUNDERSTORMS OVER SOUTHEAST SOUTH DAKOTA WILL CONTINUE TO MOVE EAST THIS MORNING INTO NORTHERN IOWA. SOME OF THESE STORMS COULD PRODUCE WIND GUSTS TO 60 MPH THIS MORNING. ADDITIONAL ACTIVITY COULD REDEVELOP LATER THIS AFTERNOON OVER THE OUTLOOK AREA AS WELL. DUE TO WARM TEMPERATURES ALOFT...ANY HAIL THAT OCCURS SHOULD REMAIN BELOW SEVERE CRITERIA...OR LESS THAN THREE-QUARTERS OF AN INCH IN DIAMETER. AS THE FRONT CONTINUES SOUTHWARD LATER THIS EVENING... ADDITIONAL SHOWERS AND THUNDERSTORMS WILL OVERSPREAD THE REST OF THE STATE WITH WIND GUSTS TO 60 MPH AND HEAVY RAIN THE PRIMARY THREAT. THE FRONT MAY STALL OUT OVER CENTRAL OR SOUTHERN IOWA OVERNIGHT... BRINGING REPEATED HEAVY RAINS TO THESE PORTIONS OF THE STATE. WITH THE RECENT HOT AND DRY WEATHER...FLOODING SHOULD NOT BE A CONCERN... THOUGH IF REPEATED HEAVY RAIN IS RECEIVED...SOME MINOR FLOODING COULD OCCUR. PRECAUTIONS -SPOTTERS MAY BE NEEDED OVER NORTHERN IOWA TODAY AND THE REST OF THE STATE TONIGHT. KEEP IN MIND THERE IS ALJSO A HEAT ADVISORY OUT FOR ABOUT THE SOUTHERN HALF OF IOWA. IF YOU MUST BE OUTSIDE IN THESE AREAS...DRINK PLENTY OF WATER AND DON/T OVEREXERT YOURSELF. SEARCY
Special weather statement, Jul 21, 6:14 AM CDT, 1 hour 12 minutes before
IAZ004>007-015>017-023>028-035>039-047>050-061-062-075-086-220000- CENTRAL IOWA THUNDERSTORM OUTLOOK...UPDATED NATIONAL WEATHER SERVICE DES MOINES IA 614 AM CDT TUE JUL 21 1998 HAZARD--SCATTERED THUNDERSTORMS WITH WIND GUSTS TO 80 MPH AND HEAVY RAINFALL. UPDATED FOR...MINOR CHANGE TO AREA OF CONCERN... AREA OF CONCERN AND TIMING DETAILS--NORTH OF A SAC CITY TO ELDORA LINE ANYTIME TODAY. SOUTHEAST OF THIS LINE THIS EVENING INTO THE OVERNIGHT HOURS. METEOROLOGICAL COMMENTS--A COLD FRONT LOCATED FROM NORTHEAST NEBRASKA THROUGH NORTHWEST IOWA INTO SOUTHEASTERN MINNESOTA WILL CONTINUE TO MOVE SOUTHEAST TODAY. MEANWHILE...LOW LEVEL SOUTHERLY WINDS WILL CONTINUE TO TRANSPORT MOISTURE NORTHWARD INTO AND OVER THE FRONT. SCATTERED THUNDERSTORMS OVER SOUTHEAST SOUTH DAKOTA WILL CONTINUE TO MOVE EAST THIS MORNING INTO NORTHERN IOWA. SOME OF THESE STORMS COULD PRODUCE WIND GUSTS TO 80 MPH THIS MORNING. ADDITIONAL ACTIVITY COULD REDEVELOP LATER THIS AFTERNOON OVER THE OUTLOOK AREA AS WELL. DUE TO WARM TEMPERATURES ALOFT...ANY HAIL THAT OCCURS SHOULD REMAIN BELOW SEVERE CRITERIA...OR LESS THAN THREE-QUARTERS OF AN INCH IN DIAMETER. AS THE FRONT CONTINUES SOUTHWARD LATER THIS EVENING... ADDITIONAL SHOWERS AND THUNDERSTORMS WILL OVERSPREAD THE REST OF THE STATE WITH WIND GUSTS TO 60 MPH AND HEAVY RAIN THE PRIMARY THREAT. THE FRONT MAY STALL OUT OVER CENTRAL OR SOUTHERN IOWA OVERNIGHT... BRINGING REPEATED HEAVY RAINS TO THESE PORTIONS OF THE STATE. WITH THE RECENT HOT AND DRY WEATHER...FLOODING SHOULD NOT BE A CONCERN... THOUGH IF REPEATED HEAVY RAIN IS RECEIVED...SOME MINOR FLOODING COULD OCCUR. PRECAUTIONS -SPOTTERS MAY BE NEEDED OVER NORTHERN IOWA TODAY AND THE REST OF THE STATE TONIGHT. KEEP IN MIND THERE IS ALSO A HEAT ADVISORY OUT FOR ABOUT THE SOUTHERN HALF OF IOWA. IF YOU MUST BE OUTSIDE IN THESE AREAS...DRINK PLENTY OF WATER AND DON/T OVEREXERT YOURSELF. SEARCY
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 21, 7:49 AM CDT | Severe Thunderstorm Warning | DMX | Emmet | 31 min |
| Jul 21, 8:00 AM CDT | Severe Thunderstorm Warning | DMX | Humboldt, Kossuth | 35 min |
| Jul 21, 8:13 AM CDT | Severe Thunderstorm Warning | DMX | Hamilton, Wright | 32 min |
| Jul 21, 8:13 AM CDT | Severe Thunderstorm Warning | DMX | Hancock, Winnebago | 32 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.