Alert archive / Iowa / Severe Thunderstorm Warnings in 1991
Severe Thunderstorm Warning 67, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at May 14, 1991, 8:07 PM CDT for Dallas County, Iowa. It was in force for 33 min.
The area
The counties it named.
The facts
- Issued
- May 14, 1991, 8:07 PM CDT (01:07 UTC)
- Expired
- May 14, 1991, 8:40 PM CDT
- In force
- 33 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
County Dallas County, IA
The nearest sounding before it
Topeka, KS (KTOP), launched 00:00Z, 1.1 hours before the alert went out and 328 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
- 1867 J/kg
- Mixed-layer CIN
- -30 J/kg
- Mixed-layer LCL
- 1053 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 135 m²/s²
- 0-3 km storm-relative helicity
- 169 m²/s²
- Significant tornado parameter
- 1.0
- Supercell composite
- 6.1
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
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 14, 4:53 PM CDT, 3 hours 14 minutes before
IAZALL-142245- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 452 PM CDT TUE MAY 14 1991 ...A FLASH FLOOD WATCH IS IN EFFECT FOR SOUTHERN IOWA FOR TONIGHT... AT 434 PM...SHOWERS AND INTENSE THUNDERSTORMS WERE LOCATED OVER EAST CENTRAL AND SOUTHEAST IOWA. THE STRONGEST STORM WAS OCCURRING 20 MILES NORTH OF OTTUMWA. THIS STORM WAS PRODUCING VERY HEAVY RAIN...DEADLY LIGHTNING...GUSTY WINDS AND POSSIBLY SOME SMALL HAIL. THESE STORMS WERE MOVING TO THE EAST AT 15 TO 20 MILES AN HOUR. INTENSE THUNDERSTORMS CONTINUED OVER NORTH CENTRAL IOWA AS WELL. THE STRONGEST STORM WAS OCCURRING 30 MILES NORTHWEST OF MASON CITY. THIS STORM WAS ALSO PRODUCING VERY HEAVY RAIN...DANGEROUS LIGHTNING...STRONG GUSTY WINDS AND POSSIBLY SMALL HAIL. THE THUNDERSTORMS WERE MOVING NORTH AT 15 TO 20 MILES AN HOUR. BARLOW/KALLMAN
Special weather statement, May 14, 5:19 PM CDT, 2 hours 48 minutes before
IAZALL-142315- SPECIAL WEATHER STATEMENT AND IOWA WEATHER UPDATE NATIONAL WEATHER SERVICE DES MOINES IA 515 PM CDT TUE MAY 14 1991 ...A FLASH FLOOD WATCH IS IN EFFECT FOR SOUTHERN IOWA FOR TONIGHT... ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR EXTREME SOUTH CENTRAL AND SOUTHEAST IOWA UNTIL 11 PM... AT 510 PM...SHOWERS AND THUNDERSTORMS WERE LOCATED OVER CENTRAL AND NORTH CENTRAL IOWA...EXTENDING FROM 20 MILES WEST OF DES MOINES TO NEAR MASON CITY. THE STRONGEST STORMS WERE LOCATED 30 MILES SOUTHWEST AND 10 MILES SOUTHWEST OF MASON CITY. THESE STORMS WERE PRODUCING VERY HEAVY RAIN...DANGEROUS LIGHTNING...AND HAIL. THE PRECIPITATION WAS MOVING NORTH AT AROUND 20 MILES AN HOUR. SHOWERS AND STRONG THUNDERSTORMS WERE ALSO OVER SOUTHEAST IOWA FROM 25 MILES NORTH OF OTTUMWA TO 10 MILES WEST OF BURLINGTON. THE SHOWERS AND STORMS WERE MOVING SOUTHEAST AT 20 MILES AN HOUR. BARLOW/KALLMAN
Special weather statement, May 14, 5:50 PM CDT, 2 hours 17 minutes before
IAZALL-142345- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 550 PM CDT TUE MAY 14 1991 ...A FLASH FLOOD WATCH IS IN EFFECT FOR SOUTHERN IOWA FOR TONIGHT... ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR EXTREME SOUTH CENTRAL AND SOUTHEAST IOWA UNTIL 11 PM... AT 535 PM...SHOWERS AND INTENSE THUNDERSTORMS CONTINUED OVER CENTRAL AND NORTH CENTRAL IOWA. THE STRONGEST STORMS WERE LOCATED 10 MILES WEST OF DES MOINES...10 MILES SOUTHWEST OF MASON CITY NEAR GARNER...AND 30 TO 40 MILES SOUTHWEST OF MASON CITY. THESE STORMS WERE PRODUCING VERY HEAVY RAIN...DEADLY LIGHTNING...AND PEA TO MARBLE SIZE. LARGER HAIL IS POSSIBLE WITH THE STORMS OVER NORTH CENTRAL IOWA. THE PRECIPITATION WAS MOVING NORTH AT AROUND 20 MILES AN HOUR. SHOWERS AND STRONG THUNDERSTORMS ALSO CONTINUED OVER SOUTHEAST IOWA FROM OTTUMWA TO BURLINGTON. THE SHOWERS AND STORMS WERE MOVING SOUTHEAST AT 20 MILES AN HOUR. BARLOW/KALLMAN
Special weather statement, May 14, 6:19 PM CDT, 1 hour 48 minutes before
IAZALL-150015- SPECIAL WEATHER STATEMENT AND IOWA WEATHER UPDATE NATIONAL WEATHER SERVICE DES MOINES IA 619 PM CDT TUE MAY 14 1991 ...A FLASH FLOOD WATCH IS IN EFFECT FOR SOUTHERN IOWA FOR TONIGHT... ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR EXTREME SOUTH CENTRAL AND SOUTHEAST IOWA UNTIL 11 PM... AT 610 PM...SHOWERS AND INTENSE THUNDERSTORMS CONTINUED OVER CENTRAL AND NORTH CENTRAL IOWA. THE STRONGEST STORMS WERE LOCATED 25 MILES EAST OF FORT DODGE...10 MILES NORTHWEST OF FORT DODGE AND 30 MILES SOUTHWEST OF MASON CITY. THESE STORMS WERE PRODUCING VERY HEAVY RAIN...DANGEROUS LIGHTNING...AND PEA TO MARBE SIZE OR LARGER HAIL. THE SHOWERS AND STORMS WERE MOVING NORTH AT AROUND 20 MILES AN HOUR. SHOWERS AND INTENSE THUNDERSTORMS WERE ALSO OVER SOUTHEAST IOWA. THE STRONGEST STORM WAS OCCURRING 15 MILES SOUTH OF BURLINGTON. THIS STORM WAS ALSO PRODUCING HEAVY RAIN...DEADLY LIGHTNING AND POSSIBLY SOME HAIL. THE PRECIPITATION WAS MOVING SOUTHEAST AT 20 MILES AN HOUR. IN ADDITION...SHOWERS WERE BEGINNING TO MOVE NORTH FROM MISSOURI INTO EXTREME SOUTH CENTRAL IOWA...25 MILES EAST OF LAMONI. BARLOW/KALLMAN
Special weather statement, May 14, 6:51 PM CDT, 1 hour 16 minutes before
IAZ002-003-007-150200- SPECIAL WEATHER STATEMENT AND WEATHER UPDATE FOR NORTHEAST IOWA NATIONAL WEATHER SERVICE WATERLOO IA 640 PM CDT TUE MAY 14 1991 AT 640 PM AN AREA OF VERY STRONG THUNDERSTORMS BEGAN 15 MILES SOUTHWEST OF HAMPTON IN WRIGHT AND HAMILTON COUNTY NEAR WILLIAMS AND DOWS AND EXTENDED NORTH TO THE IOWA/MINNESOTA BORDER NEAR LAKE MILLS. THESE STORMS WERE A PART OF A LARGER AREA OF LIGHTER RAIN WHICH WAS FALLING TO THE NORTHWEST OF A LINE CONNECTING ACKLEY NASHUA AND OSAGE. THIS AREA OF RAIN AND THUNDERSTORMS WERE MOVING TO THE NORTH AT 15 MILES AN HOUR. THE OUTLOOK FOR THE REST FOR THE EARLY EVENING HOURS IS FOR THE SKIES OVER NORTHEAST IOWA TO REMAIN VARIABLY CLOUDY WITH A CONTINUING CHANCE OF SCATTERED SHOWERS AND THUNDERSTORMS. THE WINDS WILL BLOW OUT OF THE SOUTHEAST AT 10 TO 15 MILES AN HOUR WHILE THE TEMPERATURES WILL SLOWLY FALL INTO THE MIDDLE 70S. TS
Special weather statement, May 14, 6:54 PM CDT, 1 hour 13 minutes before
IAZALL-150045- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 653 PM CDT TUE MAY 14 1991 ...A FLASH FLOOD WATCH IS IN EFFECT FOR SOUTHERN IOWA FOR TONIGHT... ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR EXTREME SOUTH CENTRAL AND SOUTHEAST IOWA UNTIL 11 PM... AT 637 PM...SHOWERS AND INTENSE THUNDERSTORMS CONTINUED OVER CENTRAL AND NORTH CENTRAL IOWA. THE STRONGEST STORMS WERE LOCATED JUST SOUTH OF DES MOINES...15 MILES NORTHWEST OF FORT DODGE AND 35 MILES WEST OF MASON CITY. THESE STORMS WERE PRODUCING VERY HEAVY RAIN...DANGEROUS LIGHTNING ...AND LARGE HAIL. THE SHOWERS AND STORMS WERE MOVING NORTH AT AROUND 20 MILES AN HOUR. SHOWERS AND VERY STRONG THUNDERSTORMS WERE ALSO OVER SOUTHEAST IOWA... FROM 40 MILES WEST TO 20 MILES SOUTH OF BURLINGTON. THE PRECIPITATION WAS MOVING SOUTHEAST AT 20 MILES AN HOUR. BARLOW/KALLMAN
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 14, 7:10 PM CDT | Severe Thunderstorm Warning | DMX | Marion | 42 min |
| May 15, 3:23 PM CDT | Severe Thunderstorm Warning | DMX | Jasper, Marshall | 22 min |
Nearby
Severe Thunderstorm Warnings in Iowa, 1991Every severe thunderstorm warning in 1991
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.