Alert archive / South Dakota / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 30, NWS Aberdeen, SD

May 21, 2007Corson County, South Dakota

NWS Aberdeen, SD issued this severe thunderstorm warning at May 21, 2007, 8:22 PM MDT for Corson County, South Dakota. It was in force for 23 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
May 21, 2007, 8:22 PM MDT (02:22 UTC)
Expired
May 21, 2007, 8:45 PM MDT
In force
23 min
Issued by
NWS Aberdeen, SD
Area
Counties, with a storm outline in the text

County Corson County, SD

The radar

The Bismarck radar (KBIS), 123 km from the middle of the area, began a volume at 02:23 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
May 21, 1:52 PM MDTSevere Thunderstorm WatchSPC8 hr

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 00:00Z, 2.4 hours before the alert went out and 124 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-pSkew-T log-p diagram, Bismarck Municip, ND at 00:00Z on 2007-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1843 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Bismarck Municip, ND at 00:00Z on 2007-05-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 37 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
1843 J/kg
Mixed-layer CIN
-57 J/kg
Mixed-layer LCL
1774 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
37 m²/s²
0-3 km storm-relative helicity
70 m²/s²
Significant tornado parameter
0.1
Supercell composite
2.2

Open this sounding in Storm Lab

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.

NWS Aberdeen, SD wrote its last area forecast discussion before this severe thunderstorm warning went out at May 21, 7:46 PM MDT, 36 minutes earlier.

Area forecast discussion, May 21, 7:46 PM MDT, 36 minutes before
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Hazardous weather outlook, May 21, 4:46 AM MDT, 15 hours 36 minutes before
HAZARDOUS WEATHER OUTLOOK...CORRECTED
NATIONAL WEATHER SERVICE ABERDEEN SD
546 AM CDT MON MAY 21 2007

SDZ003>005-007-009>011-015>017-019-033>037-045-048-051-221100-
CORSON-CAMPBELL-MCPHERSON-MARSHALL-WALWORTH-EDMUNDS-DAY-DEWEY-
POTTER-FAULK-CLARK-STANLEY-SULLY-HUGHES-HYDE-HAND-JONES-LYMAN-
BUFFALO-
546 AM CDT MON MAY 21 2007 /446 AM MDT MON MAY 21 2007/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL SOUTH
DAKOTA...NORTH CENTRAL SOUTH DAKOTA AND NORTHEAST SOUTH DAKOTA.

.DAY ONE...TODAY AND TONIGHT

SHOWERS AND THUNDERSTORMS ARE POSSIBLE ACROSS CENTRAL AND
NORTHEAST SOUTH DAKOTA TODAY INTO TONIGHT...AS A LOW PRESSURE
SYSTEM SLIDES EAST OUT OF EASTERN WYOMING. THERE IS A SLIGHT RISK
FOR SEVERE THUNDERSTORMS THIS AFTERNOON INTO TONIGHT. BESIDES THE
THREAT OF DANGEROUS LIGHTNING...THE MAIN SEVERE THUNDERSTORM
THREATS ARE LARGE HAIL AND DAMAGING WINDS.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

THE ACTIVE PATTERN WILL CONTINUE ACROSS THE AREA INTO TUESDAY AND
WEDNESDAY...BRINGING ADDITIONAL CHANCES FOR SHOWERS AND
THUNDERSTORMS. AT THIS TIME SMALL HAIL...STRONG WINDS...HEAVY
RAINFALL AND FREQUENT LIGHTNING ARE THE MAIN THREATS WITH ANY
THUNDERSTORM DEVELOPMENT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON INTO TONIGHT.

SDZ006-018-221100-
BROWN-SPINK-
546 AM CDT MON MAY 21 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST SOUTH
DAKOTA.

.DAY ONE...TODAY AND TONIGHT

SHOWERS AND THUNDERSTORMS ARE POSSIBLE ACROSS CENTRAL AND
NORTHEAST SOUTH DAKOTA TODAY INTO TONIGHT...AS A LOW PRESSURE
SYSTEM SLIDES EAST OUT OF EASTERN WYOMING. THERE IS A SLIGHT RISK
FOR SEVERE THUNDERSTORMS THIS AFTERNOON INTO TONIGHT. BESIDES THE
THREAT OF DANGEROUS LIGHTNING...THE MAIN SEVERE THUNDERSTORM
THREATS ARE LARGE HAIL AND DAMAGING WINDS.

FLOODING IS EXPECTED TO CONTINUE ON THE JAMES RIVER FOR AN EXTENDED
PORTION OF TIME. SEE THE LATEST FLOOD STATEMENT FOR SPECIFIC RIVER
STAGE INFORMATION.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

THE ACTIVE PATTERN WILL CONTINUE ACROSS THE AREA INTO TUESDAY AND
WEDNESDAY...BRINGING ADDITIONAL CHANCES FOR SHOWERS AND
THUNDERSTORMS. AT THIS TIME SMALL HAIL...STRONG WINDS...HEAVY
RAINFALL AND FREQUENT LIGHTNING ARE THE MAIN THREATS WITH ANY
THUNDERSTORM DEVELOPMENT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS EVENING INTO TONIGHT.

MNZ039-046-SDZ008-020>023-221100-
TRAVERSE-BIG STONE-ROBERTS-CODINGTON-GRANT-HAMLIN-DEUEL-
546 AM CDT MON MAY 21 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WEST CENTRAL
MINNESOTA AND NORTHEAST SOUTH DAKOTA.

.DAY ONE...TODAY AND TONIGHT

THE CHANCE FOR SHOWERS AND THUNDERSTORMS EXISTS ACROSS NORTHEAST
SOUTH DAKOTA AND WEST CENTRAL MINNESOTA TODAY INTO TONIGHT...AS A
LOW PRESSURE SYSTEM SLIDES EAST OUT OF EASTERN WYOMING. THERE IS A
POSSIBILITY FOR SEVERE WEATHER TONIGHT. BESIDES THE THREAT OF
DANGEROUS LIGHTNING...THE MAIN SEVERE THUNDERSTORM THREATS ARE
LARGE HAIL AND DAMAGING WINDS.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

THE ACTIVE PATTERN WILL CONTINUE ACROSS THE AREA INTO TUESDAY AND
WEDNESDAY...BRINGING ADDITIONAL CHANCES FOR SHOWERS AND
THUNDERSTORMS. AT THIS TIME SMALL HAIL...STRONG WINDS...HEAVY
RAINFALL AND FREQUENT LIGHTNING ARE THE MAIN THREATS WITH ANY
THUNDERSTORM DEVELOPMENT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED TONIGHT.

ALBRECHT

In the hours before

Local storm report, May 21, 7:21 PM MDT, 1 hour 1 minute before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ABERDEEN SD
821 PM CDT MON MAY 21 2007

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0818 PM     HAIL             3 SE ISABEL             45.37N 101.38W
05/21/2007  E0.75 INCH       DEWEY              SD   PUBLIC

            A FEW PENNEY SIZED.

&&

GILLESPIE
Local storm report, May 21, 7:21 PM MDT, 1 hour 1 minute before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ABERDEEN SD
821 PM CDT MON MAY 21 2007

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0630 PM     HAIL             3 SE ISABEL             45.37N 101.38W
05/21/2007  E0.75 INCH       DEWEY              SD   PUBLIC

            A FEW PENNEY SIZED.

&&

GILLESPIE
Local storm report, May 21, 7:42 PM MDT, 40 minutes before
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Local storm report, May 21, 7:54 PM MDT, 28 minutes before
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The office that day

Everything else NWS Aberdeen, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 21, 6:18 PM MDTSevere Thunderstorm WarningABRDewey57 min
May 21, 6:54 PM MDTSevere Thunderstorm WarningABRCorson66 min
May 21, 7:23 PM MDTSevere Thunderstorm WarningABRCorson, Dewey13 min
May 21, 7:27 PM MDTSevere Thunderstorm WarningABRCorson63 min
May 22, 1:34 PM MDTSevere Thunderstorm WarningABRHughes, Lyman41 min
May 22, 2:04 PM MDTSevere Thunderstorm WarningABRHughes, Hyde, Lyman41 min
May 22, 2:46 PM MDTSevere Thunderstorm WarningABRHand, Hyde44 min
May 22, 4:02 PM MDTSevere Thunderstorm WarningABRBrown, Spink43 min
May 22, 4:24 PM MDTFlash Flood WarningABRBrown, Spink6 hr
May 22, 4:42 PM MDTSevere Thunderstorm WarningABRBrown27 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 2007Every severe thunderstorm warning in 2007

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; radar from the NEXRAD Level II archive.