Alert archive / Iowa / Severe Thunderstorm Warnings in 1991
Severe Thunderstorm Warning 49, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at May 14, 1991, 10:36 AM CDT for Grundy County, Iowa. It was in force for 69 min. 2 reports 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, 10:36 AM CDT (15:36 UTC)
- Expired
- May 14, 1991, 11:45 AM CDT
- In force
- 69 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
County Grundy County, IA
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 14, 10:38 AM CDT | Hail 1.5 | Grundy, IA | |
| May 14, 11:12 AM CDT | Hail 0.75 | Grundy, 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
Minneapolis, MN (KSTC), launched 12:00Z, 3.6 hours before the alert went out and 280 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
- 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
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KALO 141540 SVRALO IAC075-141645- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE WATERLOO IA 1036 AM CDT TUE MAY 14 1991 THE NATIONAL WEATHER SERVICE IN WATERLOO HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1145 AM CDT FOR PEOPLE IN THE FOLLOWING LOCATION... IN CENTRAL IOWA ...GRUNDY COUNTY AT 1033 AM CDT NATIONAL WEATHER SERVICE RADAR SHOWED A SEVERE THUNDERSTORM JUST ENTERING GRUNDY COUNTY...30 MILES SOUTHWEST OF WATERLOO. THIS THUNDERSTORM WAS MOVING SLOWLY NORTH AT 10 MILES AN HOUR. THIS THUNDERSTORM WILL PRODUCE 3/4 INCH HAIL OR LARGER AND WINDS IN EXCESS OF 60 MILES AN HOUR...INTENSE LIGHTNING AND VERY HEAVY RAIN. PEOPLE IN GRUNDY CENTER...WELLSBURG AND CONRAD SHOULD BE READY TO TAKE IMMEDIATE ACTION TO PROTECT YOURSELF. IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A REINFORCED BUILDING. STAY INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED. DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...AND DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS. ROBB
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, 9:02 AM CDT, 1 hour 34 minutes before
IAZALL-140540- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 8 55 AM CDT TUE MAY 14 1991 AT 8 45 AM...A NUMBER OF INTENSE THUNDERSTORMS WERE LOCATED IN CENTRAL AND SOUTH CENTRAL IOWA. THESE THUNDERSTORMS WERE LOCATED ALONG A LINE ABOUT 15 MILES WIDE AND EXTENDING FROM JUST SOUTH OF BOONE...TO 10 MILES SOUTH OF NEVADA...OR 30 MILES NORTHWEST THROUGH 20 MILES NORTH OF DES MOINES. THESE STORMS WERE PRODUCING BRIEF VERY HEAVY RAIN...DANGEROUS LIGHTNING...AND HAIL. THE THUNDERSTORMS IN SOUTH CENTRAL IOWA WERE LOCATED JUST WEST OF CHARITON ...OR ABOUT 35 MILES SOUTHEAST OF DES MOINES. VERY HEAVY RAIN AND HAIL WAS ALSO REPORTED NEAR LUCAS. THE PRECIPITATcION WAS MOVING EAST AT 15 MILES AN HOUR. SCOTT
Special weather statement, May 14, 9:57 AM CDT, 39 minutes before
IAZALL-140540- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 9 45 AM CDT TUE MAY 14 1991 AT 9 30 AM...INTENSE THUNDERSTORMS WITH VERY HEAVY RAINS AND HAIL WERE LOCATED IN CENTRAL IOWA BETWEEN OGDEN AND NEWTON...OR 40 MILE NORTH THROUGH 30 MILES EAST OF DES MOINES. THIS AREA INCLUDED THE CITIES OF BOONE...AMES...NEVADA...AND OGDEN. IN ADDITION TO HEAVY RAINS AND HAIL ...DANGEROUS LIGHTNING AND WINDS IN EXCESS OF 50 MILES AN HOUR CAN BE EXPECTED WITH THESE STORMS. THESE STORMS WERE MOVING NORTHEAST AT 15 MILES AN HOUR. THUNDERSTORMS WITH VERY HEAVY RAINS AND HAIL WERE ALSO LOCATED IN SOUTH CENTRAL IOWA BETWEEN CHARITON AND HUMESTON...ABOUT 40 MILES SOUTH OF DES MOINES. THE PRECIPITATION WAS MOVING SOUTHEAST AT 15 MILES AN HOUR. SCOTT
Special weather statement, May 14, 10:24 AM CDT, 12 minutes before
IAZALL-140540- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 1020 AM CDT TUE MAY 14 1991 AT 10 15 AM...INTENSE THUNDERSTORMS WITH VERY HEAVY RAINS AND HAIL WERE LOCATED IN CENTRAL IOWA IN A LARGE AREA MIDWAY BETWEEN DES MOINES AND WATERLOO. THE MOST INTENSE STORMS WERE LOCATED ABOUT 10 MILES NORTH OF MARSHALLTOWN...OR MILES SOUTHWEST OF WATERLOO. VERY HEAVY RAINS...HAIL ...DANGEROUS LIGHTNING AND WINDS IN EXCESS OF 50 MILES AN HOUR 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 CORYDON AND ALLERTON...ABOUT 50 MILES SOUTH OF DES MOINES. THE PRECIPITATION WAS MOVING SOUTHEAST AT 15 MILES AN HOUR. SCOTT
Special weather statement, May 14, 10:29 AM CDT, 7 minutes before
IAZALL-140540- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 1020 AM CDT TUE MAY 14 1991 AT 10 15 AM...INTENSE THUNDERSTORMS WITH VERY HEAVY RAINS AND HAIL WERE LOCATED IN CENTRAL IOWA IN A LARGE AREA MIDWAY BETWEEN DES MOINES AND WATERLOO. THE MOST INTENSE STORMS WERE LOCATED ABOUT 10 MILES NORTH OF MARSHALLTOWN...OR 40 MILES SOUTHWEST OF WATERLOO. VERY HEAVY RAINS... HAIL...DANGEROUS LIGHTNING AND WINDS IN EXCESS OF 50 MILES AN HOUR 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 CORYDON AND ALLERTON...ABOUT 50 MILES SOUTH OF DES MOINES. THE PRECIPITATION WAS MOVING SOUTHEAST AT 15 MILES AN HOUR. SCOTT
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 14, 8:33 AM CDT | Severe Thunderstorm Warning | DMX | Lucas | 42 min |
| May 14, 8:44 AM CDT | Severe Thunderstorm Warning | DMX | Jasper, Polk, Story | 46 min |
| May 14, 9:03 AM CDT | Severe Thunderstorm Warning | DMX | Boone | 42 min |
| May 14, 9:15 AM CDT | Severe Thunderstorm Warning | DMX | Lucas | 45 min |
| May 14, 9:43 AM CDT | Severe Thunderstorm Warning | DMX | Marshall | 47 min |
| May 14, 10:00 AM CDT | Severe Thunderstorm Warning | DMX | Wayne | 45 min |
| May 14, 10:50 AM CDT | Severe Thunderstorm Warning | DMX | Wayne | 40 min |
| May 14, 11:05 AM CDT | Severe Thunderstorm Warning | DMX | Appanoose | 40 min |
| May 14, 11:17 AM CDT | Severe Thunderstorm Warning | DMX | Buchanan | 58 min |
| May 14, 11:26 AM CDT | Severe Thunderstorm Warning | DMX | Black Hawk | 64 min |
| May 14, 12:04 PM CDT | Severe Thunderstorm Warning | DMX | Fayette | 38 min |
| May 14, 12:34 PM CDT | Severe Thunderstorm Warning | DMX | Black Hawk | 41 min |
| May 14, 12:43 PM CDT | Severe Thunderstorm Warning | DMX | Benton | 47 min |
| May 14, 1:01 PM CDT | Severe Thunderstorm Warning | DMX | Linn | 44 min |
| May 14, 1:12 PM CDT | Severe Thunderstorm Warning | DMX | Buchanan | 33 min |
| May 14, 1:30 PM CDT | Severe Thunderstorm Warning | DMX | Linn | 45 min |
| May 14, 1:40 PM CDT | Tornado Warning | DMX | Linn | 35 min |
| May 14, 1:52 PM CDT | Severe Thunderstorm Warning | DMX | Benton | 21 min |
| May 14, 2:24 PM CDT | Severe Thunderstorm Warning | DMX | Benton | 66 min |
| May 14, 5:05 PM CDT | Severe Thunderstorm Warning | DMX | Wright | 40 min |
| May 14, 5:22 PM CDT | Severe Thunderstorm Warning | DMX | Cerro Gordo, Hancock | 68 min |
| May 14, 5:49 PM CDT | Severe Thunderstorm Warning | DMX | Wright | 41 min |
| May 14, 6:42 PM CDT | Severe Thunderstorm Warning | DMX | Polk, Warren | 63 min |
| May 14, 6:56 PM CDT | Tornado Warning | DMX | Polk | 34 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.