Alert archive / Minnesota / Severe Thunderstorm Warnings in 1991
Severe Thunderstorm Warning 117, NWS Twin Cities, MN
NWS Twin Cities, MN issued this severe thunderstorm warning at Jul 21, 1991, 7:33 PM CDT for Lac qui Parle County, Minnesota. It was in force for 57 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 21, 1991, 7:33 PM CDT (00:33 UTC)
- Expired
- Jul 21, 1991, 8:30 PM CDT
- In force
- 57 min
- Issued by
- NWS Twin Cities, MN
- Area
- Whole counties
County Lac qui Parle County, MN
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 21, 7:40 PM CDT | Thunderstorm Wind 78 | Lac Qui Parle, MN |
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
Aberdeen, SD (KHON), launched 00:00Z, 0.6 hours before the alert went out and 176 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
- 4391 J/kg
- Mixed-layer CIN
- -13 J/kg
- Mixed-layer LCL
- 1061 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 84 m²/s²
- 0-3 km storm-relative helicity
- 187 m²/s²
- Significant tornado parameter
- 3.3
- Supercell composite
- 20.6
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KSTC 220033 SVRSTC MNC073-220130- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE ST CLOUD MINNESOTA 733 PM CDT SUN JUL 21 1991 THE NATIONAL WEATHER SERVICE IN ST CLOUD MINNESOTA HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 830 PM CDT FOR PEOPLE IN THE FOLLOWING LOCATION... IN WEST CENTRAL MINNESOTA ...NORTHWESTERN LAC QUI PARLE COUNTY AT 7 30 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM 65 MILES WEST OF WILLMAR MINNESOTA. THIS THUNDERSTORM WAS JUST ENTERING NORTHWEST LAC QUI PARLE COUNTY. IT IS POSSIBLE THIS THUNDERSTORM WILL HAVE LARGE HAIL...STRONG DAMAGING WINDS AND VERY HEAVY RAIN. FREQUENT LIGHTNING WILL ALSO ACCOMPANY THIS THUNDERSTORM. TOWNS IN THE PATH OF THIS SEVERE THUNDERSTORM ARE MARIETTA...MADISON AND LOUISBERG. IF YOU ARE IN ANY OF THESE TOWNS...OR RURAL NORHTWEST LAC QUI PARLE COUNTY BE READ TO MOVE TO A SAFE STURDY STRUCTURE IMMEDIATELY. A TORNADO WATCH[ IS ALSO IN EFFECT FOR THE WARNED AREA. REMEMBER SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE WARNING. REMAIN CALM BUT BE ALERT TO RAPIDLY CHANGING WEATHER CONDITIONS. NNNN
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 21, 7:00 PM CDT, 33 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN 650 PM CDT SUN JUL 21 1991 ...FLASH FLOOD WATCH FOR MUCH OF SOUTHERN MINNESOTA FOR TONIGHT...INCLUDING THE TWIN CITIES METRO AREA... ...A LINE OF THUNDERSTORMS 40 MILES SOUTH OF THE TWIN CITIES WAS BEGINING TO MOVE NORTHWARD AT 10 MPH AND AT THIS RATE WILL BE IN THE SOUTHERN TWIN CITIES METRO AREA BETWEEN 730 AND 800 PM... AT 640 PM...POWERFUL THUNDERSTORMS CONTINUE DEVELOP OVER SOUTH CENTRAL AND SOUTHEAST MINNESOTA...SOUTH OF THE TWIN CITIES...AND MORE POWERFUL STORMS WERE MOVING INTO WESTERN MINNESOTA FROM THE DAKOTAS. SOME OF THESE STORMS WERE PRODUCING INTENSE FLOODING TYPE RAINFALLS...STRONG GUSTY WINDS OF 50 TO 60 MPH AND POSSIBLY SOME HAIL. THE MOST INTENSE RAINFALL WAS IN SOUTHEAST MINNESOTA NEAR THE MISSISSIPPI RIVER IN WINONA COUNTY BETWEEN ROCHESTER AND WINONA...NEAR FEEMONT AND UTICA. ANOTHER AREA OF STRONG THUNDERSTORMS WAS OVER SOUTH CENTRAL MINNESOTA...SOUTH OF NEW ULM. AND FROM MANKATO AND EAST TO WASECA AND OWATONNA. THIS IS A DANGEROUS WEATHER SITUATION...BECAUSE THE POTENTIAL FOR FLOODING AND SEVERE WEATHER IS VERY HIGH OVER SOUTHERN MINNESOTA...THIS EVENING. BE PREPARED FOR THE W ORST AND...BE PREPARED TO MOVE TP A PLACE OF SAFETY IF SEVERE WEATHER APPROACHES OR IF FLOODING IS OCCURRING.
Special weather statement, Jul 21, 7:14 PM CDT, 19 minutes before
MNZALL-220100- SPECIAL WEATHER STATEMENT...CORRECTED FOR CODING... NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN 650 PM CDT SUN JUL 21 1991 ...FLASH FLOOD WATCH FOR MUCH OF SOUTHERN MINNESOTA FOR TONIGHT...INCLUDING THE TWIN CITIES METRO AREA... ...A LINE OF THUNDERSTORMS 40 MILES SOUTH OF THE TWIN CITIES WAS BEGINING TO MOVE NORTHWARD AT 10 MPH AND AT THIS RATE WILL BE IN THE SOUTHERN TWIN CITIES METRO AREA BETWEEN 730 AND 800 PM... AT 640 PM...POWERFUL THUNDERSTORMS CONTINUE DEVELOP OVER SOUTH CENTRAL AND SOUTHEAST MINNESOTA...SOUTH OF THE TWIN CITIES...AND MORE POWERFUL STORMS WERE MOVING INTO WESTERN MINNESOTA FROM THE DAKOTAS. SOME OF THESE STORMS WERE PRODUCING INTENSE FLOODING TYPE RAINFALLS...STRONG GUSTY WINDS OF 50 TO 60 MPH AND POSSIBLY SOME HAIL. THE MOST INTENSE RAINFALL WAS IN SOUTHEAST MINNESOTA NEAR THE MISSISSIPPI RIVER IN WINONA COUNTY BETWEEN ROCHESTER AND WINONA...NEAR FEEMONT AND UTICA. ANOTHER AREA OF STRONG THUNDERSTORMS WAS OVER SOUTH CENTRAL MINNESOTA...SOUTH OF NEW ULM. AND FROM MANKATO AND EAST TO WASECA AND OWATONNA THIS IS A DANGEROUS WEATHER SITUATION...BECAUSE THE POTENTIAL FOR FLOODING AND SEVERE WEATHER IS VERY HIGH OVER SOUTHERN MINNE:SOTA...THIS EVENING. BE PREPARED FOR THE WORST AND...BE PREPARED TO MOVE TP A PLACE OF SAFETY IF SEVERE WEATHER APPROACHES OR IF FLOODING IS OCCURRING.
The office that day
Everything else NWS Twin Cities, MN issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 21, 7:41 PM CDT | Flash Flood Warning | MPX | Goodhue, Olmsted, Wabasha, Winona | 2 hr |
| Jul 21, 8:17 PM CDT | Severe Thunderstorm Warning | MPX | Chippewa, Lac qui Parle, Swift | 58 min |
| Jul 21, 8:34 PM CDT | Severe Thunderstorm Warning | MPX | Hennepin | 26 min |
| Jul 21, 10:10 PM CDT | Flash Flood Warning | MPX | Wabasha, Winona | 2 hr |
| Jul 21, 11:55 PM CDT | Flash Flood Warning | MPX | Wabasha, Winona | 5 hr |
| Jul 22, 1:57 AM CDT | Flash Flood Warning | MPX | Dodge, Goodhue, Olmsted, Steele | 3 hr |
Nearby
Severe Thunderstorm Warnings in Minnesota, 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.