Alert archive / South Dakota / Severe Thunderstorm Watches in 2005

Severe Thunderstorm Watch 621

July 7, 20058 counties in North Dakota; 14 counties in South Dakota

The Storm Prediction Center issued this severe thunderstorm watch at Jul 7, 2005, 2:30 PM MDT for 8 counties in North Dakota; 14 counties in South Dakota. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued
Jul 7, 2005, 2:30 PM MDT (20:30 UTC)
Expired
Jul 7, 2005, 10:00 PM MDT
In force
8 hr
Issued by
the Storm Prediction Center
All 22 counties

Adams County, ND, Bowman County, ND, Golden Valley County, ND, Grant County, ND, Hettinger County, ND, Morton County, ND, Slope County, ND, Stark County, ND, Bennett County, SD, Butte County, SD, Corson County, SD, Custer County, SD, Fall River County, SD, Haakon County, SD, Harding County, SD, Jackson County, SD, Lawrence County, SD, Meade County, SD, Oglala Lakota County, SD, Pennington County, SD, Perkins County, SD, Ziebach County, SD

The radar

The Rapid City radar (KUDX), 138 km from the middle of the area, began a volume at 20:32 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.

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jul 7, 3:07 PM MDTSevere Thunderstorm WarningUNRLawrence53 min
Jul 7, 3:52 PM MDTTornado WarningUNRHarding59 min
Jul 7, 4:01 PM MDTSevere Thunderstorm WarningUNRCuster, Fall River59 min
Jul 7, 5:17 PM MDTSevere Thunderstorm WarningUNRButte56 min
Jul 7, 6:17 PM MDTSevere Thunderstorm WarningUNRPerkins45 min
Jul 7, 9:21 PM MDTSevere Thunderstorm WarningBISMorton39 min
Jul 7, 10:00 PM MDTSevere Thunderstorm WarningBISBurleigh, Morton, Oliver60 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

Rapid City, SD (KUNR), launched 12:00Z, 8.5 hours before the alert went out and 144 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, Rapid City, SD at 12:00Z on 2005-07-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 190 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, Rapid City, SD at 12:00Z on 2005-07-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -18 square meters per square second.1939Sfc1 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
190 J/kg
Mixed-layer CIN
-343 J/kg
Mixed-layer LCL
2707 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
-18 m²/s²
0-3 km storm-relative helicity
8 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 072029
SEL1  
SPC WW 072029
NDZ000-SDZ000-080400-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 621
NWS STORM PREDICTION CENTER NORMAN OK
230 PM MDT THU JUL 7 2005

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

       SOUTHWESTERN NORTH DAKOTA
       WESTERN SOUTH DAKOTA

EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 230 PM UNTIL
1000 PM MDT.

HAIL TO 3 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 70
STATUTE MILES EAST AND WEST OF A LINE FROM 15 MILES NORTHEAST OF
DICKINSON NORTH DAKOTA TO 80 MILES SOUTH SOUTHEAST OF RAPID CITY
SOUTH DAKOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).

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 619...WW 620...

DISCUSSION...THUNDERSTORMS INCREASING OVER THE BLACK HILLS AND
RAPIDLY DEVELOPING ALONG A LEE TROUGH NEAR THE SD-MT/SD-WY BORDERS
LATE THIS AFTERNOON.  AIR MASS REMAINS VERY UNSTABLE AND DEEP LAYER
SHEAR PROFILES ARE FORECAST TO INCREASE LATE TODAY AND THIS EVENING.
 EXPECT SUPERCELLS AND MULTICELL CLUSTERS TO SPREAD SLOWLY ESEWD
THROUGH THE EVENING WITH PRIMARY THREATS OF DAMAGING WINDS AND VERY
LARGE HAIL.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 29020.


...EVANS

465,1010 425,1010 425,1035 465,1040

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 7, 4:47 PM MDTMesoscale DiscussionSPCBottineau, Burke, Dunn, McHenry, McLean, Mercer and 8 more118 min
Jul 7, 5:45 PM MDTSevere Thunderstorm WatchSPCBenson, Bottineau, Burke, Burleigh, Dunn, Kidder and 13 more7 hr
Jul 7, 5:48 PM MDTMesoscale DiscussionSPCAdams, Bowman, Golden Valley, Grant, Hettinger, Morton and 3 more87 min
Jul 7, 1:01 PM MDTMesoscale DiscussionSPCBennett, Butte, Custer, Fall River, Jackson, Lawrence and 3 more89 min

Nearby

Severe Thunderstorm Watches in South Dakota, 2005Severe Thunderstorm Watches in North Dakota, 2005Every severe thunderstorm watch in 2005

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.