Alert archive / South Dakota / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 145, NWS Rapid City, SD

August 23, 2002Pennington County, South Dakota

NWS Rapid City, SD issued this severe thunderstorm warning at Aug 23, 2002, 3:00 PM MDT for Pennington County, South Dakota. It was in force for 45 min. 2 reports 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: Aug 23, 2002, 3:00 PM MDT (21:00 UTC)
Expired: Aug 23, 2002, 3:45 PM MDT
In force: 45 min
Issued by: NWS Rapid City, SD
Area: Counties, with a storm outline in the text

County Pennington County, SD

What was reported inside it

Time	Report	Where	Remark
Aug 23, 3:05 PM MDT	Hail 1	Keystone, SD
Aug 23, 3:20 PM MDT	Hail 1.75	Keystone, SD

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.

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 12:00Z, 9.0 hours before the alert went out and 349 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 855 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: -8 m²/s²
0-3 km storm-relative helicity: 306 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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 Rapid City, SD wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 23, 2:15 PM MDT, 45 minutes earlier.

Area forecast discussion, Aug 23, 2:15 PM MDT, 45 minutes before

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
215 PM MDT FRI AUG 23 2002

STRONG UPR LOW OR/ID BDR SHOWING LITTLE MOVEMENT PER WATER VAPOR
IMAGERY. A JET STREAK IS DEPICTED OVER NRN UT...AND IS AIDING IN
CONVECTIVE DVLPMT ACRS THE NRN ROCKIES. TSTMS OVR THE BLKHLS HAVE
ALREADY REACHED SVR CRITERIA WITH LARGE HAIL. MAIN FCST CONCERNS
CENTERED AROUND HEAVY RAIN POTENTIAL THROUGH SAT...WITH THE
POSSIBILITY OF SOME STORMS CONTAINING LARGE HAIL.

EXPECT ACTIVITY TO CONT TO DEVELOP AND MOVE EWD ACRS THE CWFA
THROUGH SAT...AS 700MB TROF ROTATES THROUGH NRN PLAINS.  SE FLOW
WILL CONT TO DEEPEN...AND LATEST HODOGRAPHS INDICATE SHEAR WILL
INCREASE SOMEWHAT TONIGHT FOR POTENTIAL ROTATING UPDRAFTS. BIGGEST
CONCERN REMAINS HEAVY RAIN POTENTIAL AS STORM MOVEMENT WILL BE VERY
SLOW.

BY SAT NIGHT...700MB TROF MOVS N/E OF CWFA CUTTING OFF DEEP MOISTURE
SOURCE. HOWEVER...WILL NEED TO LEAVE POPS IN FCST THRU REMAINDER OF
3 DAY FCST AS MAIN UPR TROF REMAINS WEST OF AREA...KEEPING AREA
UNDER UNSTABLE SW FLOW ALOFT.

EXTENDED...TUE-WED STILL UNSETTLED AS UPR TROF CROSSES NRN PLAINS.
TEMPS SHOULD REMAIN WITHIN REACH OF CLIMO THESE DAYS. DRIER WITH
WARMING TREND EXPECTED THU-FRI AS UPR RIDGE BUILDS ACRS REGION IN
ADVANCE OF WEST COAST TROF.

.UNR...FLOOD WATCH THIS AFTN THRU SAT EVE FOR LAWRENCE COUNTY.
JOHNSON

In the hours before

Local storm report, Aug 23, 2:37 PM MDT, 23 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
237 PM MDT FRI AUG 23 2002

TIME(MDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1255 PM    ROCHFORD                  SD   .75 INCH HAIL
08/23/02   PENNINGTON                     REPORTED BY STORM
                                          SPOTTER.

0231 PM    HILL CITY                 SD   1.75 INCH HAIL
08/23/02   PENNINGTON                     REPORTED BY LAW
                                          ENFORCEMENT OFFICIAL.

0234 PM    2 E HILL CITY             SD   1 INCH HAIL
08/23/02   PENNINGTON                     FOREST SERVICE

Local storm report, Aug 23, 2:59 PM MDT, 1 minute before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
259 PM MDT FRI AUG 23 2002

TIME(MDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0245 PM    3 E HILL CITY             SD   .75 INCH HAIL
08/23/02   PENNINGTON                     REPORTED BY STORM
                                          SPOTTER.

0245 PM    HILL CITY                 SD   1.75 INCH HAIL
08/23/02   PENNINGTON                     REPORTED BY PUBLIC.

0250 PM    2 E HILL CITY             SD   1.75 INCH HAIL
08/23/02   PENNINGTON                     REPORTED BY STORM
                                          SPOTTER.

0257 PM    KEYSTONE                  SD   1.75 INCH HAIL
08/23/02   PENNINGTON                     REPORTED BY LAW
                                          ENFORCEMENT OFFICIAL.

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 23, 11:59 AM MDT	Severe Thunderstorm Warning	UNR	Pennington	46 min
Aug 23, 12:45 PM MDT	Severe Thunderstorm Warning	UNR	Pennington	60 min
Aug 23, 2:04 PM MDT	Severe Thunderstorm Warning	UNR	Pennington	56 min
Aug 23, 4:43 PM MDT	Severe Thunderstorm Warning	UNR	Pennington	47 min
Aug 23, 5:19 PM MDT	Severe Thunderstorm Warning	UNR		56 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 2002 Every severe thunderstorm warning in 2002

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.