Alert archive / Minnesota / Severe Thunderstorm Watches in 2012

Severe Thunderstorm Watch 253

May 5, 20128 counties in Minnesota; 7 counties in South Dakota

The Storm Prediction Center issued this severe thunderstorm watch at May 5, 2012, 8:18 PM CDT for 8 counties in Minnesota; 7 counties in South Dakota. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
May 5, 2012, 8:18 PM CDT (01:18 UTC)
Expired
May 5, 2012, 11:58 PM CDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt

Counties Big Stone County, MN, Chippewa County, MN, Lac qui Parle County, MN, Pope County, MN, Stevens County, MN, Swift County, MN, Traverse County, MN, Yellow Medicine County, MN, Clark County, SD, Codington County, SD, Day County, SD, Deuel County, SD, Grant County, SD, Hamlin County, SD, Roberts County, SD

The radar

The Aberdeen radar (KABR), 129 km from the middle of the area, began a volume at 01:20 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
5%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
10%
One or more gusts of 65 knots or more
5%
Ten or more severe hail reports
50%
One or more hailstones of 2 inches or more
40%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

11 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 5, 8:18 PM CDTSevere Thunderstorm WarningABRCodington, Deuel, Grant, Hamlin57 min
May 5, 8:36 PM CDTSevere Thunderstorm WarningABRCodington, Deuel, Grant, Hamlin, Roberts54 min
May 5, 8:43 PM CDTSevere Thunderstorm WarningABRClark, Codington, Hamlin47 min
May 5, 8:43 PM CDTSevere Thunderstorm WarningABRCodington, Deuel, Hamlin60 min
May 5, 8:56 PM CDTSevere Thunderstorm WarningABRBig Stone41 min
May 5, 9:01 PM CDTSevere Thunderstorm WarningMPXLac qui Parle14 min
May 5, 9:13 PM CDTSevere Thunderstorm WarningABRBig Stone, Traverse41 min
May 5, 9:23 PM CDTSevere Thunderstorm WarningABRBig Stone, Traverse41 min
May 5, 9:24 PM CDTSevere Thunderstorm WarningMPXStevens41 min
May 5, 9:27 PM CDTSevere Thunderstorm WarningMPXLac qui Parle, Yellow Medicine63 min
May 5, 9:29 PM CDTSevere Thunderstorm WarningABRDeuel16 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 1.3 hours before the alert went out and 128 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, Aberdeen, SD at 00:00Z on 2012-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Aberdeen, SD at 00:00Z on 2012-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 201 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
657 m above ground
0-6 km bulk shear
64 kt
0-1 km storm-relative helicity
201 m²/s²
0-3 km storm-relative helicity
278 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

367 
WWUS20 KWNS 060118
SEL3
SPC WW 060118
MNZ000-SDZ000-060600-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 253
NWS STORM PREDICTION CENTER NORMAN OK
820 PM CDT SAT MAY 5 2012

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

       WEST CENTRAL MINNESOTA
       NORTHEAST SOUTH DAKOTA

EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 820 PM
UNTIL 100 AM CDT.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 35
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 30 MILES WEST
NORTHWEST OF WATERTOWN SOUTH DAKOTA TO 50 MILES EAST SOUTHEAST OF
ORTONVILLE MINNESOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE
THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

OTHER WATCH INFORMATION...CONTINUE...WW 249...WW 250...WW
251...WW 252...

DISCUSSION...A CLUSTER OF ELEVATED THUNDERSTORMS WILL CONTINUE TO
SPREAD NEWD INTO NE SD/W CENTRAL MN...ALONG THE NRN FRINGE OF A WAA
REGIME WITH MUCAPE NEAR 2000 J/KG...ROOTED NEAR 800 MB.  THE
COMBINATION OF MODERATE BUOYANCY/STEEP MIDLEVEL LAPSE RATES AND
STRONG CLOUD-LAYER SHEAR WILL SUPPORT ORGANIZED STORMS CAPABLE OF
PRODUCING LARGE HAIL FOR THE NEXT FEW HOURS.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 24030.


...THOMPSON

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 5, 9:51 PM CDTMesoscale DiscussionSPCAnoka, Benton, Big Stone, Blue Earth, Brown, Carver and 29 more84 min
May 5, 10:03 PM CDTSevere Thunderstorm WatchSPCCottonwood, Jackson, Lyon, Murray, Nobles7 hr
May 5, 11:31 PM CDTMesoscale DiscussionSPCAnoka, Brown, Carver, Cottonwood, Hennepin, Jackson and 16 more89 min
May 6, 2:12 AM CDTMesoscale DiscussionSPCBlue Earth, Faribault, Freeborn, Jackson, Martin, Mower and 3 more63 min

Nearby

Severe Thunderstorm Watches in Minnesota, 2012Severe Thunderstorm Watches in South Dakota, 2012Every severe thunderstorm watch in 2012

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.