Alert archive / Iowa / Severe Thunderstorm Warnings in 1991
Severe Thunderstorm Warning 13, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Apr 8, 1991, 6:09 PM CDT for Polk County, Iowa. It was in force for 36 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
- Apr 8, 1991, 6:09 PM CDT (23:09 UTC)
- Expired
- Apr 8, 1991, 6:45 PM CDT
- In force
- 36 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
County Polk County, IA
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Apr 8, 6:18 PM CDT | Hail 0.9 | Polk, 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, 11.2 hours before the alert went out and 236 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
- NaN m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km storm-relative helicity
- 102 m²/s²
- 0-3 km storm-relative helicity
- 43 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.6
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KDSM 082309 SVRDSM IAC153-082345- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE DES MOINES IA 609 PM CDT MON APR 8 1991 THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 645 PM CDT FOR PEOPLE IN THE FOLLOWING LOCATION... IN CENTRAL IOWA ...NORTHERN POLK COUNTY AT 607 PM...LARGE HAIL WAS REPORTED IN WINDSOR HEIGHT IN DES MOINES IN CENTRAL IOWA. THIS WARNING WILL AFFECTS THE CITIES OF DES MOINES...ANKENY...BONDURANT AND ADJACENT COMMUNITIES. THE STORM WAS MOVING NORTHEAST AT 40 MILES AN HOUR. SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNINGo...AND VERY HEAVY RAIN. FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD. MCQUIRTER
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, Apr 8, 4:19 PM CDT, 1 hour 50 minutes before
IAZALL-082220- SPECIAL WEATHER STATEMENT AND WEATHER UPDATE FOR IOWA NATIONAL WEATHER SERVICE DES MOINES IA 419 PM CDT MON APR 8 1991 ...SEVERE THUNDERSTORM WATCH IN EFFECT FOR PORTIONS OF EASTERN IOWA THIS MONDAY AFTERNOON AND EVENING UNTIL 9 PM CDT... AT 410 PM...SCATTERED VERY STRONG THUNDERSTORMS CONTINUED FROM SOUTHWEST INTO NORTHEAST IOWA. THE STRONGEST STORMS WERE LOCATED IN A 20 MILE WIDE BAND EXTENDING FROM 30 MILES EAST OF COUNCIL BLUFFS NEAR OAKLAND...TO 10 MILES SOUTH OF WATERLOO. THESE STORMS ARE CAPABLE OF PRODUCING BRIEF STRONG GUSTY WINDS...VERY HEAVY RAIN...SMALL HAIL AND FREQUENT DEADLY LIGHTNING. THESE THUNDERSTORMS WERE PART OF A LARGE AREA OF SHOWERS AND STORMS OCCURRING IN A 70 MILE WIDE BAND THAT EXTENDED FROM THE SOUTHWEST CORNER OF IOWA...TO NORTHEAST IOWA 40 MILES NORTHEAST OF WATERLOO. THE SHOWERS AND STORMS WERE MOVING NORTHEAST AT 40 MILES AN HOUR WHILE THE ENTIRE AREA WAS DRIFTING EAST AT AROUND 15 MILES AN HOUR. JAK
Special weather statement, Apr 8, 4:51 PM CDT, 1 hour 18 minutes before
IAZALL-082245- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 445 PM CDT MON APR 8 1991 ...SEVERE THUNDERSTORM WATCH IN EFFECT FOR PORTIONS OF EASTERN IOWA THIS MONDAY AFTERNOON AND EVENING UNTIL 9 PM CDT... AT 430 PM...SCATTERED VERY STRONG THUNDERSTORMS CONTINUED FROM SOUTHWEST INTO NORTHEAST IOWA. THE STRONGEST STORMS WERE LOCATED IN A 20 MILE WIDE BAND EXTENDING FROM 25 MILES EAST OF COUNCIL BLUFFS... BETWEEN OAKLAND AND RED OAK...TO THE STORY CITY AND JEWELL AREAS... 40 TO 50 MILES NORTH OF DES MOINES...TO NEAR WATERLOO. OTHER STRONG STORMS WERE DETECTED 25 TO 35 MILES WEST OF LAMONI IN SOUTHWEST IOWA... AND ALONG THE MISSISSIPPI RIVER 20 MILES SOUTHEAST OF DUBUQUE. THESE STORMS CAN PRODUCE HEAVY RAINFALL...DANGEROUS LIGHTNING...SMALL HAIL...AND DAMAGING WIND. THESE STORMS WERE PART OF A LARGE SYSTEM OF SHOWERS AND THUNDERSTORMS THAT COVERED MUCH OF THE CENTRAL THIRD OF IOWA FROM THE SOUTHWEST CORNER OF THE STATE TO THE NORTHEAST CORNER. MOST OF THE SHOWERS WERE EAST OF ALINE FROM 15 MILES SOUTHEAST OF COUNCIL BLUFFS TO THE MASON CITY AREA. THE STORMS WERE MOVING NORTHEAST AT 40 MILES AN HOUR...WHILE THE AREA OF SHOWERS WAS MOVING EAST AT 15 MILES AN HOUR. MILLER/KALLMAN
Local storm report, Apr 8, 4:55 PM CDT, 1 hour 14 minutes before
LOCAL STORM REPORT
NATIONAL WEATHER SERVICE WATERLOO IA
445 PM CDT MON ARP 08 1991
EVENT AND LOCATION
BLACK HAWK COUNTY
144PM CDT WINDS AT THE AIRPORT RECORDED AT 41 MPH. AT THE
145-200PM STATION KWWL..ON ROOF 4 STORIES UP WINDS 61 MPH.
TREE AND LIMB DAMAGE
200PM ELK RUN HEIGHTS 1/2 IN HAIL WIND DAMAGE TO SMALL
BLDG. TREE DAMAGE. STRONG WINDS
BUCHANAN COUNTY
213 PM TREES DOWN IN FAIRBANKS 50 MPH WIND
215 PM 80 MPH WIND AT INDEPENDENCE AIRPORT
FRONT BLOWN OFF OLD MILL...BRICKS...
TREE DAMAGE
221 PM TREES DOWN IN BRANDON.
WINNESHIEK COUNTY
215PM 10 TREES DOWN/SEMI OFF ROAD/SHINGLES OF ROOF
221PM UNCONFIRMED FUNNELSpecial weather statement, Apr 8, 5:15 PM CDT, 54 minutes before
IAZ002-006-090000- SPECIAL WEATHER STATEMENT AND WEATHER UPDATE NATIONAL WEATHER SERVICE WATERLOO IA 515 PM CDT MON APR 08 1991 AT 510 PM CDT...A 40 MILE WIDE AREA OF SHOWERS AND SCATTERED THUNDERSTORMS EXTENDED FROM 30 MILES NORTH OF DES MOINES NEAR AMES...THROUGH WATERLOO TO THE NORTHEAST CORNER OF IOWA. THE AREA OF SHOWERS AND THUNDERSTORMS WAS MOVING TO THE EAST AT 15 MILES AN HOUR. TEMPERATURES RANGED FROM THE UPPER 40S AT MASON CITY TO THE MIDDLE 50S IN THE WATERLOO AREA. EARLY THIS EVENING SHOWERS AND THUNDERSTORMS WILL CONTINUE WITH FALLING TEMPERATURES OVER NORTHEAST IOWA FROM THE IOWA/MINNESOTA BORDER TO THE WATERLOO AND CEDAR FALLS AREA. THE WINDS WILL BE NORTH TO NORTHWEST /15 TO 25 MILES AN HOUR LATER THIS EVENING. MG
Special weather statement, Apr 8, 5:21 PM CDT, 48 minutes before
IAZALL-082315- SPECIAL WEATHER STATEMENT AND WEATHER UPDATE FOR IOWA NATIONAL WEATHER SERVICE DES MOINES IA 520 PM CDT MON APR 8 1991 ...SEVERE THUNDERSTORM WATCH IN EFFECT FOR PORTIONS OF EASTERN IOWA THIS MONDAY AFTERNOON AND EVENING UNTIL 9 PM CDT... AT 510 PM...SCATTERED VERY STRONG THUNDERSTORMS CONTINUED FROM SOUTHWEST INTO NORTH CENTRAL AND NORTHEAST IOWA. THE STRONGEST STORMS WERE LOCATED IN A CLUSTER OVER SOUTHWEST IOWA...FROM 20 TO 45 MILES SOUTHWEST OF DES MOINES...NEAR THE COMMUNITIES OF WINTERSET AND AFTON. OTHER STRONG STORMS WERE LOCATED IN A 20 MILE WIDE BAND THAT STRETCHED FROM 50 MILES SOUTHEAST OF COUNCIL BLUFFS NORTH TO THE ATLANTIC AND CUMBERLAND AREAS...50 MILES EAST OF COUNCIL BLUFFS...THEN NORTHEAST TO NEAR GRUNDY CENTER...25 MILES SOUTHWEST OF WATERLOO. THESE STORMS CAN PRODUCE HEAVY RAINFALL...DANGEROUS LIGHTNING...SMALL HAIL...AND DAMAGING WIND. / THESE STORMS WERE PART OF A LARGE SYSTEM OF SHOWERS AND THUNDERSTORMS THAT COVERED MUCH OF THE CENTRAL THIRD OF IOWA FROM THE SOUTHWEST CORNER TO THE NORTHEAST CORNER. THE STORMS WERE MOVING NORTHEAST AT 40 MILES AN HOUR...WHILE THE AREA OF SHOWERS WAS MOVING EAST AT 15 MILES AN HOUR. MILLER/KALL3MAN
Special weather statement, Apr 8, 5:47 PM CDT, 22 minutes before
IAZALL-082345- SPECIAL WEATHER STATEMENT AND WEATHER UPDATE FOR IOWA NATIONAL WEATHER SERVICE DES MOINES IA 545 PM CDT MON APR 8 1991 ...SEVERE THUNDERSTORM WATCH IN EFFECT FOR PORTIONS OF SOUTH CENTRAL ...SOUTHEAST...AND EASTERN IOWA UNTIL 9 PM CDT THIS MONDAY EVENING... AT 530 PM...SCATTERED VERY STRONG THUNDERSTORMS CONTINUED OVER SOUTHWEST ...SOUTH CENTRAL...CENTRAL...AND NORTHEAST IOWA. THE STRONGEST STORMS WERE LOCATED IN A 10 MILE WIDE BAND FROM 55 MILES SOUTHEAST OF COUNCIL BLUFFS...NEAR CORNING...TO 50 MILES WEST OF DES MOINES...NEAR ADAIR. OTHER STRONG STORMS WERE LOCATED IN A 10 TO 30 MILE WIDE BAND FROM 30 MILES NORTHWEST OF DES MOINES...TO 15 MILES WEST OF WATERLOO. THESE STORMS CAN PRODUCE HEAVY RAINFALL...DANGEROUS LIGHTNING...SMALL HAIL... AND DAMAGING WIND. THESE STORMS WERE PART A LARGE SYSTEM OF SHOWERS AND THUNDERSTORMS THAT COVERED MUCH OF CENTRAL AND NORTHEAST IOWA. THE SHOWERS WERE IN A 75 TO 100 MILE WIDE BAND THAT WAS EAST OF A LINE FROM 45 MILES SOUTHEAST OF COUNCIL BLUFFS...TO THE LAKE CITY AREA...70 MILES NORTHWEST OF DES MOINES...TO THE MASON CITY VICINITY. THE STORMS WERE MOVING NORTHEAST AT 40 MILES AN HOUR...WHILE THE SHOWERS WERE DRIFTOING EAST AT 15 MILES AN HOUR. MILLER
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 8, 11:18 AM CDT | Severe Thunderstorm Warning | DMX | Audubon, Carroll | 42 min |
| Apr 8, 2:41 PM CDT | Severe Thunderstorm Warning | DMX | Buchanan | 49 min |
| Apr 8, 6:06 PM CDT | Severe Thunderstorm Warning | DMX | Marshall, Story | 54 min |
| Apr 8, 6:26 PM CDT | Severe Thunderstorm Warning | DMX | Marshall, Story | 34 min |
| Apr 8, 6:45 PM CDT | Severe Thunderstorm Warning | DMX | Marion | 30 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.