Alert archive / Iowa / Severe Thunderstorm Warnings in 1991
Severe Thunderstorm Warning 113, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Jul 7, 1991, 10:10 AM CDT for Clay County, Dickinson County, Iowa. It was in force for 50 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
- Jul 7, 1991, 10:10 AM CDT (15:10 UTC)
- Expired
- Jul 7, 1991, 11:00 AM CDT
- In force
- 50 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
Counties Clay County, IA, Dickinson County, IA
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 7, 10:20 AM CDT | Thunderstorm Wind 73 | Clay, 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, 3.2 hours before the alert went out and 219 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
- 1724 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km storm-relative helicity
- 99 m²/s²
- 0-3 km storm-relative helicity
- 166 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 KDSM 071511 SVRDSM IAC041-059-071600- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE DES MOINES IA 1010 AM CDT SUN JUL 7 1991 THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1100 AM CDT FOR PEOPLE IN THE FOLLOWING LOCATIONS... IN NORTHWEST IOWA ...NORTHERN CLAY COUNTY...SOUTHERN DICKINSON COUNTY AT 1005 AM...RADAR INDICATED A SEVERE THUNDERSTORM OVER EXTREME NORTHWEST CLAY COUNTY AND EXTREME SOUTHWEST DICKINSON COUNTY. THE STORM WAS MOVING EAST AT 45 TO 50 MILES AN HOUR. THE STORM WAS 15 MILES NORTHWEST OF SPENCER. SMALL HAIL...WINDS IN EXCESS OF 60 MILES AN HOUR...BRIEF EXTREMELY HEAVY RAIN AND FREQUENT DEADLY LIGHTNING CAN BE EXPECTED WITH THIS STORM. COMMUNITIES IN THE PATH OF THIS STORM ARE SPENCER...MILFORD...AND FOSTORIA. PEOPLE IN THE PATH OF THIS STORM SHOULD SEEK SHELTER AT ONCE. REPORT ALL INSTANCES OF SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...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. BIKLE
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, Jul 7, 4:32 AM CDT, 5 hours 38 minutes before
IAZ002-003-007-071030- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE WATERLOO IA 425 AM CDT SUN JUL 7 1991 AT 425 AM CDT A LINE OF SHOWERS AND LOCALLY INTENSE THUNDERSTORMS WERE LOCATED ALONG A LINE BEGINNING 15 MILES SOUTHEAST OF DECORAH AND EXTENDING SOUTHEAST TO THE IOWA/WINSCONSIN BORDER 5 MILES SOUTH OF PRARIE DU CHIEN. THESE STORMS WERE MOVING TO THE EAST AT AROUND 30 MILES AN HOUR. THE STRONGEST OF THESE STORMS WERE LOCATED 5 MILES SOUTH OF PRARIE DU CHIEN AND WERE ABOUT TO MOVE INTO WISCONSIN. SPEECE
Special weather statement, Jul 7, 8:48 AM CDT, 1 hour 22 minutes before
IAZALL-071440- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 846 AM CDT SUN JUL 7 1991 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR PART OF NORTHWEST IOWA UNTIL 1PM... AT 835 AM...SCATTERED THUNDERSTORMS WERE MOVING INTO THE EXTREME NORTHWEST CORNER OF IOWA. THESE THUNDERSTORMS WERE SOME 40 TO 60 MILES NORTH OF SIOUX CITY...NEAR ROCK RAPIDS...ROCK VALLEY AND HULL. IT APPEARS THAT MUCH STRONGER THUNDERSTORMS WILL BE ENTERING EXTREME NORTHWEST IOWA FROM SOUTHEAST SOUTH DAKOTA BY ABOUT 930 AM. THE PRECIPITATION OVER NORTHWEST IOWA WAS MOVING EAST SOUTHEAST AT 35 MILES AN HOUR. THERE WERE ISOLATED SHOWERS AND THUNDERSTORMS OVER SOUTH CENTRAL IOWAQ. THESE SHOWERS AND STORMS WERE LOCATED SOME 35 TO 55 MILES SOUTH OF DES MOINES...NEAR OSCEOLA...LAMONI...LEAON AND ALLERTON. THESE SHOWERS AND STORMS WERE MOVING EAST AT 30 MILES AN HOUR. BARLOW
Special weather statement, Jul 7, 8:53 AM CDT, 1 hour 17 minutes before
IAZALL-071440- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY...CORRECTED LAST PARA. NATIONAL WEATHER SERVICE DES MOINES IA 846 AM CDT SUN JUL 7 1991 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR PART OF NORTHWEST IOWA UNTIL 1PM... AT 835 AM...SCATTERED THUNDERSTORMS WERE MOVING INTO THE EXTREME NORTHWEST CORNER OF IOWA. THESE THUNDERSTORMS WERE SOME 40 TO 60 MILES NORTH OF SIOUX CITY...NEAR ROCK RAPIDS...ROCK VALLEY AND HULL. IT APPEARS THAT MUCH STRONGER THUNDERSTORMS WILL BE ENTERING EXTREME NORTHWEST IOWA FROM SOUTHEAST SOUTH DAKOTA BY ABOUT 930 AM. THE PRECIPITATION OVER NORTHWEST IOWA WAS MOVING EAST SOUTHEAST AT 35 MILES AN HOUR. THERE WERE ISOLATED SHOWERS AND THUNDERSTO]RMS OVER SOUTH CENTRAL IOWA. THESE SHOWERS AND STORMS WERE LOCATED SOME 35 TO 55 MILES SOUTH OF DES MOINES...NEAR OSCEOLA...LAMONI...LEON AND ALLERTON. THESE SHOWERS AND STORMS WERE MOVING EAST AT 30 MILES AN HOUR. BARLOW
Special weather statement, Jul 7, 9:17 AM CDT, 53 minutes before
IAZALL-071515- SPECIAL WEATHER STATEMENT AND WEATHER UPDATE FOR IOWA NATIONAL WEATHER SERVICE DES MOINES IA 915 AM CDT SUN JUL 7 1991 AT 910 AM...A LINE OF INTENSE THUNDERSTORMS WAS MOVING INTO THE EXTREME NORTHWEST CORNER OF IOWA. THIS LINE WAS LOCATED SOME 20 TO 60 MILES NORTH OF SIOUX CITY...NEAR AKRON...HAWARDEN...ROCK VALLEY AND LESTER. THESE STORMS ARE CAPABLE OF PRODUCING EXTREMELY HEAVY RAIN...LARGE HAIL...DAMAGING THUNDERSTORM WINDS IN EXCESS OF 50 TO 60 MILES AN HOUR ALONG WITH FREQUENT DEADLY LIGHTNING. THIS LINE OF STORMS WAS MOVING EAST SOUTHEAST AT 50 TO 55 MILES AN HOUR. ISOLATED SHOWERS AND THUNDERSTORMS WERE LOCATED OVER THE SOUTHERN TIER OF IOWAS COUNTIES FROM 70 MILES SOUTHWEST OF DES MOINES...NEAR BEDFORD EAST TO NEAR BLOOMFIELD OR 20 MILES SOUTH OF OTTUMWA. THESE SHOWERS AND STORMS WERE MOVING EAST AT 30 MILES AN HOUR. THE OUTLOOK THROUGH 10 AM...SHOWERS AND THUNDERSTORMS WILL CONTINUE TO SPREAD OVER FAR NORTHWEST IOWA...WITH ISOLATED SHOWERS AND STORMS OVER THE SOUTHERN TIER OF IOWAS COUNTIES. BARLOW
Special weather statement, Jul 7, 9:55 AM CDT, 15 minutes before
IAZALL-071540- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 950 AM CDT SUN JUL 7 1991 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR PART OF NORTHWEST IOWA UNTIL 1PM... AT 935 AM...A LINE OF INTENSE THUNDERSTORMS WAS LOCATED OVER FAR NORTHWEST IOWA. THIS LINE OF STORMS EXTENDED FROM 25 MILES NORTH OF SIOUX CITY...NEAR LE MARS TO 60 MILES NORTH OF SIOUX CITY...NEAR ROCK RAPIDS. THESE STORMS WILL PRODUCE BRIEF EXTREMELY HEAVY RAIN...LARGE HAIL... WINDS IN EXCESS OF 70 MILES AN HOUR AND FREQUENT DEADLY LIGHTNING. THESE STORMS WERE PART OF A LARGER AREA OF SHOWERS AND STORMS. THE LEADING EDGE OF THIS COMPLEX EXTENDED FROM 20 MILES NORTHWEST OF SPENCER SOUTHEAST TO STORM LAKE OR ABOUT 50 MILES NORTHEAST OF SIOUX CITY. THESE SHOWERS AND STORMS WERE MOVING EAST SOUTHEAST AT 45 TO 50 MILES AN HOUR. ISOLATED SHOWERS AND STORMS PERSISTED OVER THE SOUTHERN TIER OF IOWAS COUNTIES FROM MOUNT AYR...55 MILES SOUTHWEST OF DES MOINES EAST TO MOULTON OR 30 MILES SOUTHWEST OF OTTUMWA. THESE SHOWERS AND STORMS WERE MOVING EAST AT 30 MILES AN HOUR. BARLOW
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 7, 10:35 AM CDT | Severe Thunderstorm Warning | DMX | Buena Vista, Palo Alto, Pocahontas | 40 min |
| Jul 7, 10:35 AM CDT | Severe Thunderstorm Warning | DMX | Emmet | 40 min |
| Jul 7, 10:50 AM CDT | Severe Thunderstorm Warning | DMX | Kossuth | 40 min |
| Jul 7, 11:08 AM CDT | Severe Thunderstorm Warning | DMX | Hancock, Winnebago | 44 min |
| Jul 7, 11:40 AM CDT | Severe Thunderstorm Warning | DMX | Cerro Gordo | 35 min |
| Jul 7, 11:45 AM CDT | Severe Thunderstorm Warning | DMX | Franklin | 24 min |
| Jul 7, 11:57 AM CDT | Severe Thunderstorm Warning | DMX | Butler, Floyd, Mitchell | 33 min |
| Jul 7, 12:29 PM CDT | Severe Thunderstorm Warning | DMX | Bremer, Chickasaw | 31 min |
| Jul 7, 12:29 PM CDT | Severe Thunderstorm Warning | DMX | Howard | 31 min |
| Jul 7, 12:53 PM CDT | Severe Thunderstorm Warning | DMX | Allamakee, Fayette | 37 min |
| Jul 7, 1:13 PM CDT | Severe Thunderstorm Warning | DMX | Allamakee | 32 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.