Alert archive / Iowa / Tornado Warnings in 1991
Tornado Warning 5, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this tornado warning at Aug 7, 1991, 6:09 PM CDT for Cherokee County, Plymouth County, Iowa. It was in force for 36 min.
The area
The counties it named.
The facts
- Issued
- Aug 7, 1991, 6:09 PM CDT (23:09 UTC)
- Expired
- Aug 7, 1991, 6:45 PM CDT
- In force
- 36 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Whole counties
Counties Cherokee County, IA, Plymouth County, IA
The nearest sounding before it
Omaha, NE (KOVN), launched 12:00Z, 11.2 hours before the alert went out and 162 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
- 1226 J/kg
- Mixed-layer CIN
- -202 J/kg
- Mixed-layer LCL
- 1659 m above ground
- 0-6 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 114 m²/s²
- 0-3 km storm-relative helicity
- 67 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 KSUX 072319 COR
TORSUX
IAC035-149-072345-
BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED
TORNADO WARNING...CORRECTION
NATIONAL WEATHER SERVICE SIOUX CITY IA
618 PM CDT WED AUG 7 1991
THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING
EFFECTIVE UNTIL 645 PM CDT FOR PEOPLE IN THE FOLLOWING
COUNTIES
IN THE NORTHWEST PART OF IOWA
WESTERN CHEROKEE...EASTERN PLYMOUTH
AT 555 PM CDT PLYMOUTH COUNTY EMERGENCY SERVICES REPORTED A TORNADO
ON THE GROUND 5 MILES EAST OF REMSEN IOWA OR 30 MILES NORTHEAST OF
SIOUX CITY.
MOVEMENT WAS EAST AT 10 MPH
MARCUS IOWA IS IN THE PATH OF THE STORM.
THIS IS A DANGEROUS STORM. TAKE COVER IMMEDIATELY. IF YOU ARE IN A
STRONG BUILDING GO TO AN INTERIOR ROOM ON THE LOWEST FLOOR. AVOID
WINDOWS. ABANDON CARS AND MOBILE HOMES FOR A REINFORCED BUILDING OR
GET INTO A DITCH OR DEPRESSION...COVER YOUR HEAD WITH YOUR HANDS.
ASK THE NEAREST LAW ENFORCEMENT AGENCY TO RELAY YOUR REPORTS OF
SEVERE WEATHER TO THE NATIONAL WEATHER SERVICE.
HOPPES...CORRECTION IN 2ND PARA...TORNADO ON THE GROUNDWhat forecasters said that day
The local office's own words before this tornado 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, Aug 7, 4:10 PM CDT, 1 hour 59 minutes before
SDZ018-019-020-072200- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 410 PM CDT WED AUG 7 1991 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR PORTIONS OF SOUTHEAST SOUTH DAKOTA UNTIL 1000 PM CDT... SHOWERS AND THUNDERSTORMS DEVELOPED ACROSS SOUTHEAST SOUTH DAKOTA THIS AFTERNOON. THE STORMS EXTENDED FROM CHARLES MIX COUNTY TO MOODY COUNTY AND WERE MOVING NORTHEAST AT 10 MILES AN HOUR. THUNDERSTORMS WILL CONTINUE OVER SOUTHEAST SOUTH DAKOTA THIS EVENING... AND SOME STORMS MAY BE SEVERE. IF A THUNDERSTORM APPROACHES YOUR AREA ...SEEK SHELTER INSIDE A REINFORCED BUILDING IMMEDIATELY. ALSO REMEMBER THAT LIGHTNING IS EXTREMELY DANGEROUS. MENTZER
Special weather statement, Aug 7, 4:36 PM CDT, 1 hour 33 minutes before
IAZ001-004-005-072230- SPECIAL WEATHER STATEMENT AND WEATHER UPDATE NATIONAL WEATHER SERVICE SIOUX CITY IA 430 PM CDT WED AUG 7 1991 ...SEVERE THUNDERSTORM WATCH FOR MUCH OF THE SIOUXLAND AREA TIL 10 PM... AT 425 PM...SCATTERED STRONG THUNDERSTORMS WERE LOCATED BETWEEN ELK POINT SOUTH DAKOTA...20 MILES NORTHWEST OF SIOUX CITY AND DIXON NEBRASKA ...30 MILES SOUTHWEST OF SIOUX CITY. AN AREA OF SHOWERS WAS BETWEEN AKRON AND ORANGE CITY IOWA OR 25 MILES NORTHWEST TO 40 MILES NORTHEAST OF SIOUX CITY. THE STORMS AND SHOWERS WERE MOVING NORTHEAST AT 35 MILES AN HOUR. THE STRONGER STORMS WERE LIKELY PRODUCING BRIEF HEAVY AND SOME SMALL HAIL. THE STORMS WILL MOVE INTO ELK POINT SOUTH DAKOTA AROUND 5 PM. PEOPLE IN EXTREME SOUTHEAST SOUTH DAKOTA AND FAR NORTHEAST NEBRASKA SHOULD BE ALERT FOR RAPIDLY CHANGING WEATHER CONDITIONS...AND BE PREPARED TO MOVE TO A PLACE OF SAFETY. S. QUINN
Special weather statement, Aug 7, 4:41 PM CDT, 1 hour 28 minutes before
IAZ001-072230- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 440 PM CDT WED AUG 7 1991 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR PORTIONS OF SOUTHEAST SOUTH DAKOTA AND NORTHWEST IOWA UNTIL 1000 PM CDT... AT 435 PM CDT A STRONG THUNDERSTORM HAD DEVELOPED OVER NORTHWEST IOWA... 35 MILES NORTH OF SIOUX CITY OR JUST EAST OF HAWARDEN. THIS STORM SHOWED LITTLE MOVEMENT. PERSONS NEAR THE STORM SHOULD BE PREPARED FOR THIS TIHREATENING WEATHER. VERY HEAVY RAINS...GUSTY WINDS...HAIL...AND FREQUENT LIGHTNING CAN BE EXPECTED WITH THIS STORM. GEELHART
Special weather statement, Aug 7, 5:42 PM CDT, 27 minutes before
SDZ018-020-072330- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 540 PM CDT WED AUG 7 1991 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR PORTIONS OF SOUTHEAST SOUTH DAKOTA AND NORTHWEST IOWA UNTIL 1000 PM CDT... AT 535 PM CDT A LINE OF STRONG THUNDERSTORMS EXTENDED FROM 20 MILES NORTHEAST OF YANKTON TO 30 MILES WEST OF YANKTON. THE LINE WAS MOVING NORTHEAST AT 20 MPH. ANOTHER STRONG STORM WAS LOCATED 5 MILES SOUTHWEST OjF BERESFORD. THIS STORM WAS ALSO MOVING NORTHEAST AT 20 MPH. PERSONS NEAR THE PATH OF THESE STORMS SHOULD BE ON THE LOOKOUT FOR THIS THREATENING WEATHER. VERY HEAVY RAIN...GUSTY WINDS...AND HAIL ARE POSSIBLE WITH THESE STORMS. GEELHART
Special weather statement, Aug 7, 5:58 PM CDT, 11 minutes before
SDZ018-020-IAZ001-072345- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 555 PM CDT WED AUG 7 1991 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR PORTIONS OF SOUTHEAST SOUTH DAKOTA AND NORTHWEST IOWA UNTIL 1000 PM CDT... THE SEVERE THUNDERSTORM WARNING FOR SOUTHEAST SIOUX COUNTY WILL BE ALLOWED TO EXPIRE AT 6 PM. AT 555 PM CDT SCATTERED THUNDERSTORMS CONTINUED IN SOUTHEAST SOUTH DAKOTA. THE STRONGEST THUNDERSTORMS WERE LOCATED IN YANKTON COUNTY. THE STORMS WERE MOVING EAST AT 30 MPH. PERSONS IN THE PATH OF THESE STORMS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER. VERY HEAVY RAIN...GUSTY WINDS...AND DEADLY LIGHTNING ARE ALL POSSIBLE FROM THESE STORMS. GEELLHART
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 7, 5:02 PM CDT | Severe Thunderstorm Warning | FSD | Plymouth | 28 min |
| Aug 7, 5:08 PM CDT | Severe Thunderstorm Warning | FSD | Sioux | 52 min |
| Aug 7, 5:38 PM CDT | Severe Thunderstorm Warning | FSD | Plymouth | 67 min |
Nearby
Tornado Warnings in Iowa, 1991Every tornado warning in 1991Tornadoes 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.