Alert archive / Iowa / Severe Thunderstorm Warnings in 1991

Severe Thunderstorm Warning 57, NWS Des Moines, IA

May 14, 1991Linn County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 14, 1991, 1:01 PM CDT for Linn County, Iowa. It was in force for 44 min.

The area

The counties it named.

The facts

Issued
May 14, 1991, 1:01 PM CDT (18:01 UTC)
Expired
May 14, 1991, 1:45 PM CDT
In force
44 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Linn County, IA

The nearest sounding before it

Minneapolis, MN (KSTC), launched 12:00Z, 6.0 hours before the alert went out and 348 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, Minneapolis, MN 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, Minneapolis, MN at 12:00Z on 1991-05-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 120 square meters per square second.19395878Sfc1 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
3158 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
120 m²/s²
0-3 km storm-relative helicity
111 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, 10:47 AM CDT, 2 hours 14 minutes before
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Special weather statement, May 14, 11:23 AM CDT, 1 hour 38 minutes before
IAZALL-141740-

SPECIAL WEATHER STATEMENT AND IOWA WEATHER UPDATE
NATIONAL WEATHER SERVICE DES MOINES IA
1115 AM CDT TUE MAY 14 1991

AT 11 10 AM...INTENSE THUNDERSTORMS WITH VERY HEAVY RAINS AND HAIL WERE
LOCATED IN NORTHEAST IOWA IN THE WATERLOO AREA.  THE MOST INTENSE STORMS
WERE LOCATED BETWEEN GRUNDY CENTER AND WATERLOO...AND ALSO NEAR WALKER
...ABOUT 30 MILES SOUTHEAST OF WATERLOO  VERY HEAVY RAINS...HAIL...AND
DANGEROUS LIGHTNING CAN BE EXPECTED WITH THESE STORMS.

THESE STORMS WERE MOVING NORTHEAST AT 15 MILES AN HOUR.

THUNDERSTORMS WITH VERY HEAVY RAINS AND HAIL CONTINUED IN SOUTH CENTRAL
IOWA.  THESE STORMS WERE LOCATED NEAR SEYMOUR...CENTERVILLE AND MYSTIC
...25 THROUGH 50 MILES SOUTHWEST OF OTTUMWA.

THESE STORMS WERE MOVING SOUTHEAST AT 15 MILES AN HOUR.

SCOTT
Special weather statement, May 14, 11:47 AM CDT, 1 hour 14 minutes before
IAZALL-141740-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1145 AM CDT TUE MAY 14 1991

AT 11 40 AM...INTENSE THUNDERSTORMS WITH VERY HEAVY RAINS AND HAIL WERE
LOCATED IN NORTHEAST IOWA IN THE WATERLOO AREA.  THE MOST INTENSE STORMS
WERE LOCATED ABOUT 10 MILES SOUTHWEST OF WATERLOO.  THESE STORMS WERE
MOVING TO THE NORTHEAST AT 20 MILES AN HOUR.  VERY HEAVY RAINS...HAIL...
NAD DANGEROUS LIGHTNING CAN BE EXPECTED WITH THESE STORMS.

THESE STORMS WERE MOVING NORTHEAST AT 15 MILES AN HOUR.

THUNDERSTORMS WITH VERY HEAVY RAINS AND HAIL CONTINUED IN SOUTH CENTRAL
IOWA.  THE HEAVIEST OF THESE STORMS WAS LOCATED OVER RATHBUN RESERVOIR
...ABOUT 40 MILES SOUTHLEAST OF OTTUMWA.  VERY HEAVY RAINS...LIGHTNING...
AND HAIL CAN ALSO BE EXPECTED WITH THESE STORMS.

THESE STORMS WERE MOVING SOUTHEAST AT 15 MILES AN HOUR.
SCOTT
Special weather statement, May 14, 11:53 AM CDT, 1 hour 8 minutes before
IAZALL-141740-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1145 AM CDT TUE MAY 14 1991

AT 11 40 AM...INTENSE THUNDERSTORMS WITH VERY HEAVY RAINS AND HAIL WERE
LOCATED IN NORTHEAST IOWA IN THE WATERLOO AREA.  THE MOST INTENSE STORMS
WERE LOCATED ABOUT 10 MILES SOUTHWEST OF WATERLOO.  THESE STORMS WERE
MOVING TO THE NORTHEAST AT 20 MILES AN HOUR.  VERY HEAVY RAINS...HAIL...
NAD DANGEROUS LIGHTNING CAN BE EXPECTED WITH THESE STORMS.

THESE STORMS WERE MOVING NORTHEAST AT 15 MILES AN HOUR.

THUNDERSTORMS WITH VERY HEAVY RAINS AND HAIL CONTINUED IN SOUTH CENTRAL
IOWA.  THE HEAVIEST OF THESE STORMS WAS LOCATED OVER RATHBUN RESERVOIR
...ABOUT 40 MILES S[OUTHWEST OF OTTUMWA.  VERY HEAVY RAINS...LIGHTNING...
AND HAIL CAN ALSO BE EXPECTED WITH THESE STORMS.

THESE STORMS WERE MOVING SOUTHEAST AT 15 MILES AN HOUR.
SCOTT
Special weather statement, May 14, 12:18 PM CDT, 43 minutes before
IAZALL-141840-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1220 PM CDT TUE MAY 14 1991

AT 12 15 PM...INTENSE THUNDERSTORMS WITH VERY HEAVY RAINS AND HAIL WERE
LOCATED IN NORTHEAST IOWA IN THE WATERLOO AREA.  THE MOST INTENSE STORMS
WERE LOCATED ABOUT 10 MILES SOUTHEAST OF WATERLOO.  THESE STORMS WERE
MOVING TO THE NORTHEAST AT 20 MILES AN HOUR.  VERY HEAVY RAINS...HAIL...
NAD DANGEROUS LIGHTNING CAN BE EXPECTED WITH THESE STORMS.

THUNDERSTORMS WITH VERY HEAVY RAINS AND HAIL CONTINUED IN SOUTH CENTRAL
IOWA.  THE HEAVIEST OF THESE STORMS WAS LOCATED ABOUT 15 MILES WEST OF
OTTUMWA...NEAR ALBIA.  VERY HEAVY RAINS AND HAIL CAN ALSO BE EXPECTED
WITH THESE STORMS.

THESE STORMS WERE ALSO MOVING NORTHEAST AT 15 MILES AN HOUR.

SCOTT
Special weather statement, May 14, 12:48 PM CDT, 13 minutes before
IAZALL-141840-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1245 PM CDT TUE MAY 14 1991

AT 12 40 PM...INTENSE THUNDERSTORMS WITH VERY HEAVY RAINS WERE LOCATED
IN NORTHEAST IOWA IN THE WATERLOO AREA.  THE MOST INTENSE STORMS WERE
LOCATED ABOUT 15 MILES SOUTH THROUGH EAST OF WATERLOO.  THESE STORMS
WERE MOVING TO THE NORTHEAST AT 20 MILES AN HOUR.  VERY HEAVY RAINS...
HAIL AND DANGEROUS LIGHTNING CAN BE EXPECTED WITH THESE STORMS.

THUNDERSTORMS WITH HEAVY RAINS WERE ALSO LOCATED IN EAST CENTRAL AND
SOUTH CENTRAL IOWA.  THE THUNDERSTORMS IN SOUTH CENTRAL IOWA HAD
DECREASED IN INTENSITY.

HEAVY RAINS WERE ALSO ASSOCIATED WITH THE THUNDERSTORMS IN EAST CENTRAL
IOWA.  THESE THUNDERSTORMS WERE LOCATED JUST EAST OF CEDAR RAPIDS NEAR
TIPTON...AND ALSO NEAR DEWITT AND MAQUOKETA...MIDWAY BETWEEN DAVENPORT
AND DUBUQUE.
THESE STORMS WERE ALSO MOVING TO THE NORTHEAST AT 20 MILES AN HOUR.

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, 1:12 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, 6:42 PM CDTSevere Thunderstorm WarningDMXPolk, Warren63 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; the sounding from the Mesonet's radiosonde archive.