Alert archive / Iowa / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 280, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Aug 3, 1998, 6:00 PM CDT for Marshall County, Iowa. It was in force for 35 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Aug 3, 1998, 6:00 PM CDT (23:00 UTC)
- Expired
- Aug 3, 1998, 6:35 PM CDT
- In force
- 35 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
County Marshall County, IA
The radar
The Des Moines radar (KDMX), 69 km from the middle of the area, began a volume at 23:01 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.
The nearest sounding before it
Davenport, (KDVN), launched 12:00Z, 11.0 hours before the alert went out and 212 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
- 1272 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km storm-relative helicity
- 115 m²/s²
- 0-3 km storm-relative helicity
- 191 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KDSM 032300 RRA SVRDSM IAC127-032335- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE DES MOINES IA 600 PM CDT MON AUG 3 1998 THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... SOUTHERN MARSHALL COUNTY IN CENTRAL IOWA * UNTIL 635 PM CDT * AT 558 PM CDT... DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 33 MILES NORTHEAST OF DES MOINES OR 7 MILES WEST SOUTHWEST OF HAVERHILL MOVING EAST AT 25 MPH. * THIS STORM CAN BE EXPECTED NEAR... LA MOILLE BY 600 PM CDT HAVERHILL BY 610 PM CDT LAUREL BY 615 PM CDT MARSHALLTOWN BY 617 PM CDT FERGUSON BY 623 PM CDT | SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE WARNING. GO INSIDE A STURDY BUILDING AND STAY AWAY FROM WINDOWS! DEROY
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, Aug 3, 5:35 PM CDT, 25 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086- 092>097-041100- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 535 PM CDT MON AUG 3 1998 HAZARD -SCATTERED THUNDERSTORMS CAPABLE OF PRODUCING WEAK LANDSPOUT TORNADOES...ESPECIALLY IN NORTHWEST AND NORTH CENTRAL IOWA...RAINFALL RATES OF 1 TO 2 INCHES PER HOUR...HAIL THREE QUARTERS OF AN INCH OR LARGER AND WIND GUSTS TO 40 OR 50 MPH. AREA OF CONCERN -THE THREAT OF LANDSPOUT TORNADOES IS CONFINED MAINLY TO NORTHWEST AND NORTH CENTRAL IOWA EARLY THIS EVENING. SCATTERED THUNDERSTORMS WITH HEAVY RAIN...MARBLE SIZE HAIL AND GUSTY WINDS ARE POSSIBLE OVER ALL OF CENTRAL IOWA. TIMING -THUNDERSTORM DEVELOPMENT WILL CONTINUE THIS EVENING WITH STRONG AND POSSIBLY A FEW SEVERE STORMS POSSIBLE THROUGH 9 OR 10 PM. METEOROLOGICAL COMMENTS -A LOW PRESSURE SYSTEM OVER SOUTHEAST SOUTH DAKOTA WILL MOVE VERY SLOWLY SOUTHEAST. SEVERAL FRONTAL BOUNDARIES WERE IN PLACE OVER IOWA HELPING FOCUS THE DEVELOPMENT OF THUNDERSTORMS. SCATTERED THUNDERSTORMS HAVE DEVELOPED OVER THE NORTHWEST QUARTER OF THE STATE THIS AFTERNOON ALONG THE COLD FRONT. STRONG CIRCULATION IN THIS AREA HAS CAUSED A FEW OF THE STORMS TO PRODUCE WEAK LANDSPOUTS. THE AIRMASS OVER ALL OF CENTRAL IOWA REMAINS UNSTABLE SO THUNDERSTORMS WILL CONTINUE TO DEVELOP. MOST OF THE STORMS ARE NOT EXPECTED TO BE SEVERE...HOWEVER WITH PULSE TYPE STORMS...A FEW COULD PRODUCE HAIL SLIGHTLY LARGER THAN THREE QUARTERS OF AN INCH AND STRONG WINDS. AFTER SUNSET...SHOWERS AND THUNDERSTORMS MAY CONTINUE BUT THE THREAT OF SEVERE WEATHER WILL DIMINISH AND THE PRIMARY THREAT WILL BECOME HEAVY RAINFALL. PRECAUTIONS -WIDESPREAD ACTIVATION OJF SPOTTERS IS NOT EXPECTED THIS EVENING...HOWEVER EMERGENCY MANAGERS AND SPOTTERS SHOULD REMAIN ALERT TO THE POSSIBILITY OF ISOLATED SEVERE STORMS AND HEAVY RAINFALL THAT COULD PRODUCE URBAN STREET FLOODING. STARK
Special weather statement, Aug 3, 5:35 PM CDT, 25 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086- 092>097-041100- CENTRAL IOWA THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 535 PM CDT MON AUG 3 1998 HAZARD -SCATTERED THUNDERSTORMS CAPABLE OF PRODUCING WEAK LANDSPOUT TORNADOES...ESPECIALLY IN NORTHWEST AND NORTH CENTRAL IOWA...RAINFALL RATES OF 1 TO 2 INCHES PER HOUR...HAIL THREE QUARTERS OF AN INCH OR LARGER AND WIND GUSTS TO 40 OR 50 MPH. AREA OF CONCERN -THE THREAT OF LANDSPOUT TORNADOES IS CONFINED MAINLY TO NORTHWEST AND NORTH CENTRAL IOWA EARLY THIS EVENING. SCATTERED THUNDERSTORMS WITH HEAVY RAIN...MARBLE SIZE HAIL AND GUSTY WINDS ARE POSSIBLE OVER ALL OF CENTRAL IOWA. TIMING -THUNDERSTORM DEVELOPMENT WILL CONTINUE THIS EVENING WITH STRONG AND POSSIBLY A FEW SEVERE STORMS POSSIBLE THROUGH 9 OR 10 PM. METEOROLOGICAL COMMENTS -A LOW PRESSURE SYSTEM OVER SOUTHEAST SOUTH DAKOTA WILL MOVE VERY SLOWLY SOUTHEAST. SEVERAL FRONTAL BOUNDARIES WERE IN PLACE OVER IOWA HELPING FOCUS THE DEVELOPMENT OF THUNDERSTORMS. SCATTERED THUNDERSTORMS HAVE DEVELOPED OVER THE NORTHWEST QUARTER OF THE STATE THIS AFTERNOON ALONG THE COLD FRONT. STRONG CIRCULATION IN THIS AREA HAS CAUSED A FEW OF THE STORMS TO PRODUCE WEAK LANDSPOUTS. THE AIRMASS OVER ALL OF CENTRAL IOWA REMAINS UNSTABLE SO THUNDERSTORMS WILL CONTINUE TO DEVELOP. MOST OF THE STORMS ARE NOT EXPECTED TO BE SEVERE...HOWEVER WITH PULSE TYPE STORMS...A FEW COULD PRODUCE HAIL SLIGHTLY LARGER THAN THREE QUARTERS OF AN INCH AND STRONG WINDS. AFTER SUNSET...SHOWERS AND THUNDERSTORMS MAY CONTINUE BUT THE THREAT OF SEVERE WEATHER WILL DIMINISH AND THE PRIMARY THREAT WILL BECOME HEAVY RAINFALL. PRECAUTIONS -WIDESPREAD ACTIVATION OJF SPOTTERS IS NOT EXPECTED THIS EVENING...HOWEVER EMERGENCY MANAGERS AND SPOTTERS SHOULD REMAIN ALERT TO THE POSSIBILITY OF ISOLATED SEVERE STORMS AND HEAVY RAINFALL THAT COULD PRODUCE URBAN STREET FLOODING. STARK
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 3, 5:10 PM CDT | Severe Thunderstorm Warning | DMX | Wapello | 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.