Alert archive / Iowa / Severe Thunderstorm Warnings in 1991

Severe Thunderstorm Warning 41, NWS Sioux Falls, SD

May 29, 1991Cherokee County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at May 29, 1991, 2:00 AM CDT for Cherokee County, Iowa. It was in force for 60 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, 2:00 AM CDT (07:00 UTC)
Expired: May 29, 1991, 3:00 AM CDT
In force: 60 min
Issued by: NWS Sioux Falls, SD
Area: Whole counties

County Cherokee County, IA

What was reported inside it

Time	Report	Where	Remark
May 29, 2:20 AM CDT	Thunderstorm Wind 50	Cherokee, 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, 7.0 hours before the alert went out and 169 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

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

Open this sounding in Storm Lab

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 29, 12:41 AM CDT, 1 hour 19 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, 44 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, 41 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

Special weather statement, May 29, 1:33 AM CDT, 27 minutes before

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Special weather statement, May 29, 1:48 AM CDT, 12 minutes before

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Special weather statement, May 29, 1:58 AM CDT, 2 minutes before

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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, 1:19 AM CDT	Severe Thunderstorm Warning	FSD	Plymouth	56 min
May 29, 12:35 AM CDT	Severe Thunderstorm Warning	FSD	Dixon	55 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1991 Every 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.