Alert archive / Iowa / Severe Thunderstorm Warnings in 1991
Severe Thunderstorm Warning 40, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at May 29, 1991, 1:19 AM CDT for Plymouth County, Iowa. It was in force for 56 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
- May 29, 1991, 1:19 AM CDT (06:19 UTC)
- Expired
- May 29, 1991, 2:15 AM CDT
- In force
- 56 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Whole counties
County Plymouth County, IA
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 29, 1:22 AM CDT | Thunderstorm Wind 78 | Plymouth, 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 00:00Z, 6.3 hours before the alert went out and 158 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
- 2095 J/kg
- Mixed-layer CIN
- -73 J/kg
- Mixed-layer LCL
- 1829 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 121 m²/s²
- 0-3 km storm-relative helicity
- 49 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 8.8
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
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 28, 11:03 PM CDT, 2 hours 16 minutes before
SDZ016>020-290500- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 1100 PM CDT TUE MAY 28 1991 ...TORNADO WATCH FOR THE EAST PART OF SOUTH CENTRAL AND ALL OF SOUTH EAST SOUTH DAKOTA EXPIRES AT 11 PM CDT... ...SEVERE THUNDERSTORM WATCH FOR PART OF SOUTH CENTRAL AND PART OF SOUTHEAST SOUTH DAKOTA UNTIL 4 AM CDT... THE TORNADO WATCH HAS EXPIRED BUT A SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED FOR A SMALL PART OF SOUTH CENTRAL AND SOUTHEAST SOUTH DAKOTA UNTIL 4 AM CDT. AT 11 PM CDT THUNDERSTORMS...SOME WITH SMALL HAIL AND VERY HEAVY RAIN AND STRONG WINDS COVERED A LARGE PART OF SOUTH CENTRAL SOUTH DAKOTA. ALSO SOME OF THE THUNDERSTORMS WERE OVER THE WEST PART OF SOUTHEAST SOUTH DAKOTA. THE STROMS WERE MOVING TO THE NORTHEAST AT 40 MPH. IF SEVERE WEATHER APPROACHES TAKE COVER. IF YOU GET SEVERE WEATHER CALL YOUR NEAREST LAW ENFORCEMENT AGENCY AND REPORT THE SEVERE WEATHER. KOSCIELSKI
Special weather statement, May 28, 11:19 PM CDT, 2 hours before
IAZ001-004-005-280500- SPECIAL WEATHER STATEMENT AND WEATHER UPDATE FOR SIOUX CITY AND VICINITY NATIONAL WEATHER SERVICE SIOUX CITY IA 1118 AM CDT TUE MAY 28 1991 ...SEVERE THUNDERSTORM WATCH IN EFFECT FOR THE SIOUXLAND AREA TIL 4 AM.. AT 11 PM A LINE OF STRONG THUNDERSTORMS WAS LOCATED FROM 20 MILES WEST OF SIOUX FALLS SOUTH DAKOTA TO NORFOLK NEBARSKA. THIS LINE WAS MOVING EAST AT 40 MPH. THIS LINE OF STORMS IS EXPECTED TO MOVE INTO THE COUNTDIES OF DIXON AND THURSTON BY 1 AM. STRONG GUSTY WINDS DANGEROUS LIGHTNING AND SMALL HAIL MAY BE EXPECTED WITH THIS LINE OF STORMS. TANNER
Special weather statement, May 28, 11:38 PM CDT, 1 hour 41 minutes before
SDZ005-016-017-018-019-290530- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE HURON SD 1135 PM CDT TUE MAY 28 1991 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR SOUTHEAST SOUTH DAKOTA... AT 1130 PM CDT...NUMEROUS THUNDERSTORMS CONTINUED OVER CENTRAL AN EASTERN SOUTH DAKOTA...EAST OF A LINE FROM MOBRIDGE TO MISSION AND SOUTH AND WEST OF A LINE FROM ABERDEEN TO SIOUX FALLS. THE STRONGEST STORMS WERE SOUTH OF A LINE FROM BROOKINGS TO CHAMBERLAIN. MOVEMENT WAS NORTHEAST AT 35 MILES AN HOUR. SPRINGER
Special weather statement, May 29, 12:41 AM CDT, 38 minutes before
SDZ018-290700- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 1240 AM CDT WED MAY 29 1991 ...SEVERE THUNDERSTORM WATCH FOR PARTS OF SOUTHEAST SOUTH DAKOTA... A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR PARTS OF SOUTHEAST SOUTH DAKOTA UNTIL 5 AM CDT. AT 1230 PM CDT A LINE OF STRONG THUNDERSTORMS EXTENDED FROM 20 MILES EAST OF YANKTON NEAR VERMILLION TO 5 MILES WEST OF SIOUX FALLS TO TO BROOKINGS MOVING EAST AT 55 MPH. THESE THUNDERSTORMS HAVE PRODUCED WINDS FROM 40 TO 55 MPH AND PERIODS OF VERY HEAVY RAIN. DANGEROUS CLOUD TO GROUND LIGHTNING IS ALSO POSSIBLE WITH THIS LINE OF THUNDERSTORMS. PERSONS IN THE PATH OF THESE THUNDERSTORMS SHOULD BE PREPARED FOR TH5IS ADVERSE WEATHER AND MOVE TO A SAFE REINFORCED SHELTER IF NECESSARY. KEEP UP WITH THE LATEST WEATHER INFORMATION. BLOOM
Special weather statement, May 29, 1:16 AM CDT, 3 minutes before
SDZ004-005-011-012-017-018-020-290630- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE HURON SD 1200 AM CDT WED MAY 29 1991 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR EAST CENTRAL SOUTH DAKOTA... AT MIDNIGHT CDT...NUMEROUS THUNDERSTORMS CONTINUED OVER CENTRAL AND EASTERN SOUTH DAKOTA...ALONG AND EAST OF THE MISSOURI RIVER. THE STRONGEST STORMS WERE IN A 20 MILE WIDE BAND FROM 35 MILES SOUTHEAST TO 20 MILES SOUTHWEST O[F WATERTOWN. MOVEMENT WAS NORTHEAST AT 35 MILES AN HOUR. SPRINGER
Special weather statement, May 29, 1:19 AM CDT, 0 minutes before
SDZ004-005-011-012-017-018-020-290630- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY...CORRECTED FOR TIME NATIONAL WEATHER SERVICE HURON SD 100 AM CDT WED MAY 29 1991 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR EAST CENTRAL SOUTH DAKOTA... AT 1 AM CDT...NUMEROUS THUNDERSTORMS CONTINUED OVER CENTRAL AND EASTERN SOUTH DAKOTA...ALONG AND EAST OF THE MISSOURI RIVER. THE STRONGEST STORMS WERE IN A 20 MILE WIDE BAND FROM 35 MILES SOUTHEAST TO ]20 MILES SOUTHWEST OF WATERTOWN. MOVEMENT WAS NORTHEAST AT 35 MILES AN HOUR. SPRINGER
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 28, 11:13 PM CDT | Severe Thunderstorm Warning | FSD | Bon Homme, Charles Mix, Douglas | 62 min |
| May 28, 11:28 PM CDT | Severe Thunderstorm Warning | FSD | Hutchinson | 62 min |
| May 28, 11:38 PM CDT | Severe Thunderstorm Warning | FSD | Yankton | 52 min |
| May 28, 11:57 PM CDT | Severe Thunderstorm Warning | FSD | Hanson, McCook, Turner | 48 min |
| May 29, 12:24 AM CDT | Severe Thunderstorm Warning | FSD | Clay | 36 min |
| May 29, 1:05 AM CDT | Severe Thunderstorm Warning | FSD | Union | 55 min |
| May 29, 1:19 AM CDT | Severe Thunderstorm Warning | FSD | Woodbury | 56 min |
| May 29, 2:00 AM CDT | Severe Thunderstorm Warning | FSD | Cherokee | 60 min |
| May 29, 12:35 AM CDT | Severe Thunderstorm Warning | FSD | Dixon | 55 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.