Alert archive / Iowa / Severe Thunderstorm Warnings in 1991

Severe Thunderstorm Warning 65, NWS Des Moines, IA

May 14, 1991Polk County, Warren County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 14, 1991, 6:42 PM CDT for Polk County, Warren County, Iowa. It was in force for 63 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 14, 1991, 6:42 PM CDT (23:42 UTC)
Expired
May 14, 1991, 7:45 PM CDT
In force
63 min
Issued by
NWS Des Moines, IA
Area
Whole counties

Counties Polk County, IA, Warren County, IA

What was reported inside it

TimeReportWhereRemark
May 14, 7:05 PM CDTThunderstorm Wind 50Polk, 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. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Omaha, NE (KOVN), launched 12:00Z, 11.7 hours before the alert went out and 235 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.

Skew-T log-pSkew-T log-p diagram, Omaha, NE at 12:00Z on 1991-05-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 12:00Z on 1991-05-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -52 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
NaN m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
-52 m²/s²
0-3 km storm-relative helicity
-3 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

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, 4:16 PM CDT, 2 hours 26 minutes before
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Special weather statement, May 14, 4:33 PM CDT, 2 hours 9 minutes before
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Special weather statement, May 14, 4:53 PM CDT, 1 hour 49 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, 1 hour 23 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, 52 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, 23 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

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 14, 8:33 AM CDTSevere Thunderstorm WarningDMXLucas42 min
May 14, 8:44 AM CDTSevere Thunderstorm WarningDMXJasper, Polk, Story46 min
May 14, 9:03 AM CDTSevere Thunderstorm WarningDMXBoone42 min
May 14, 9:15 AM CDTSevere Thunderstorm WarningDMXLucas45 min
May 14, 9:43 AM CDTSevere Thunderstorm WarningDMXMarshall47 min
May 14, 10:00 AM CDTSevere Thunderstorm WarningDMXWayne45 min
May 14, 10:36 AM CDTSevere Thunderstorm WarningDMXGrundy69 min
May 14, 10:50 AM CDTSevere Thunderstorm WarningDMXWayne40 min
May 14, 11:05 AM CDTSevere Thunderstorm WarningDMXAppanoose40 min
May 14, 11:17 AM CDTSevere Thunderstorm WarningDMXBuchanan58 min
May 14, 11:26 AM CDTSevere Thunderstorm WarningDMXBlack Hawk64 min
May 14, 12:04 PM CDTSevere Thunderstorm WarningDMXFayette38 min
May 14, 12:34 PM CDTSevere Thunderstorm WarningDMXBlack Hawk41 min
May 14, 12:43 PM CDTSevere Thunderstorm WarningDMXBenton47 min
May 14, 1:01 PM CDTSevere Thunderstorm WarningDMXLinn44 min
May 14, 1:12 PM CDTSevere Thunderstorm WarningDMXBuchanan33 min
May 14, 1:30 PM CDTSevere Thunderstorm WarningDMXLinn45 min
May 14, 1:40 PM CDTTornado WarningDMXLinn35 min
May 14, 1:52 PM CDTSevere Thunderstorm WarningDMXBenton21 min
May 14, 2:24 PM CDTSevere Thunderstorm WarningDMXBenton66 min
May 14, 5:05 PM CDTSevere Thunderstorm WarningDMXWright40 min
May 14, 5:22 PM CDTSevere Thunderstorm WarningDMXCerro Gordo, Hancock68 min
May 14, 5:49 PM CDTSevere Thunderstorm WarningDMXWright41 min
May 14, 6:56 PM CDTTornado WarningDMXPolk34 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.