Alert archive / South Dakota / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 200, NWS Sioux Falls, SD

July 28, 2002Sanborn County, South Dakota

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jul 28, 2002, 1:25 PM CDT for Sanborn County, South Dakota. It was in force for 35 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 28, 2002, 1:25 PM CDT (18:25 UTC)
Expired: Jul 28, 2002, 2:00 PM CDT
In force: 35 min
Issued by: NWS Sioux Falls, SD
Area: Counties, with a storm outline in the text

County Sanborn County, SD

The radar

The Sioux Falls radar (KFSD), 117 km from the middle of the area, began a volume at 18:27 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 6.4 hours before the alert went out and 100 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: 99 J/kg
Mixed-layer CIN: -249 J/kg
Mixed-layer LCL: 1295 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 36 m²/s²
0-3 km storm-relative helicity: 255 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.4

Open this sounding in Storm Lab

The text

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

336 
WUUS53 KFSD 281825
SVRFSD
SDC111-281900-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
125 PM CDT SUN JUL 28 2002

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SANBORN COUNTY IN EAST CENTRAL SOUTH DAKOTA

* UNTIL 200 PM CDT

* AT 125 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 3 MILES EAST OF FORESTBURG...OR ABOUT 21 MILES
  NORTH OF MITCHELL...MOVING EAST AT 20 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  ARTESIAN AROUND 135 PM CDT

THIS STORM WILL PRODUCE LARGE HAIL. GO INSIDE A STURDY BUILDING AND
STAY AWAY FROM WINDOWS.

LAT...LON 4409 9819 4392 9810 4390 9786 4420 9788

BOUSTEAD

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 Sioux Falls, SD wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 28, 10:32 AM CDT, 2 hours 53 minutes earlier.

Area forecast discussion, Jul 28, 10:32 AM CDT, 2 hours 53 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1032 AM CDT SUN JUL 28 2002

GOING FORECAST IN GOOD SHAPE.  WEAK SFC LOW OVR SE SD AT 15Z AND NEW
MESOETA DEPICTS THIS QUITE WELL.  LO LVL MOISTURE POOLING OVR SE
SD...SW MN AND NW IA WITH SFC DEW PTS IN THE LOW 70S MID MRNG.
FAIRLY WELL DEFINED SHORT WAVE OVR EASTERN WY EARLY THIS MRNG...AND
MESOETA ALSO SEEMS TO HAVE GOOD HANDLE ON THIS FEATURE.  SHORTWAVE
TO LIFT NORTHEAST INTO NE SD BY MID AFTRN...HELPING TO
DESTABLIZE ATMOSPHERE OVER ERN SD AND ADJOINING AREAS.  NOT MUCH OF
A CAP NOW AND WITH FURTHER COOLING ALOFT EXPECTED THIS AFTRN...RAPID
TSTRM INITIATION LIKELY AS CONVECTIVE TEMPS ARE HIT THIS AFTRN.
CURRENT ZONES INDICATE SVR THREAT OVR MUCH OF SE PORTION OF CWA FOR
AFTRN INTO EVE AND THIS LOOKS VERY GOOD.  MAIN THREAT TO BE LARGE
HAIL...BUT KOMA SOUNDING SHOWS STRONG WIND POTENTIAL AS
WELL...ESPECIALLY ACROSS NW IA.  STORMS ALREADY FIRING OVR CNTRL
NEBRASKA...AN INDICATION OF THINGS TO COME FOR FSD CWA LATER TODAY.
WARMEST TEMPS TO BE OVR EXTREME SE SD AND NW IA IN ADVANCE OF SFC
LOW PRES.  MID 90S IN THESE AREAS LIKELY...WITH 70 PLUS DEW PTS FOR
A HOT HUMID AFTERNOON.  SLIGHTLY COOLER...DRIER AIR OVR NW PORTION
OF CWA.  SVR WEATHER THREAT SHOULD END LATE EVENING AS THE COOLER
DRIER AIR OVR NW PORTION OF CWA FILTERS SOUTHEAST ACROSS THE REST OF
THE CWA.

.FSD...NONE
HARMON

In the hours before

Special weather statement, Jul 28, 11:00 AM CDT, 2 hours 25 minutes before

SIGNIFICANT WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1100 AM CDT SUN JUL 28 2002

*** THIS SIGNIFICANT WEATHER OUTLOOK FROM THE NATIONAL WEATHER SERVICE
PERTAINS ONLY TO CONDITIONS ASSOCIATED WITH THUNDERSTORMS. ***

.SYNOPSIS...
LOW PRESSURE OVER SOUTHEAST SOUTH DAKOTA WILL BE THE FOCUS FOR
THUNDERSTORM DEVELOPMENT THIS AFTERNOON INTO THE EVENING OVER
SOUTHEAST SOUTH DAKOTA...SOUTHWEST MINNESOTA AND NORTHWEST IOWA.  THE
ATMOSPHERE WILL BE MOST UNSTABLE OVER EXTREME SOUTHEAST SOUTH
DAKOTA...NORTHWEST IOWA..AND SOUTHWEST MINNESOTA LATE AFTERNOON AND
EVENING.  THIS AREA WILL HAVE THE GREATEST RISK OF SEVERE
WEATHER...WITH LARGE HAIL THE MAIN THREAT.  HOWEVER...DAMAGING WINDS
AND VERY HEAVY RAIN WILL ALSO BE POSSIBLE...ESPECIALLY ACROSS
NORTHWEST IOWA AND PORTIONS OF SOUTHWEST MINNESOTA LATE AFTERNOON AND
EVENING.  THE SEVERE WEATHER THREAT SHOULD END ACROSS THE AREA AROUND
MIDNIGHT.

SDZ038>040-050-052>061-063>065-068-290500-
BEADLE-KINGSBURY-BROOKINGS-JERAULD-SANBORN-MINER-LAKE-MOODY-BRULE-
AURORA-DAVISON-HANSON-MCCOOK-GREGORY-CHARLES MIX-DOUGLAS-HUTCHINSON-
BON HOMME-
INCLUDING THE CITIES OF...HURON...BROOKINGS...CHAMBERLAIN...MITCHELL...
1100 AM CDT SUN JUL 28 2002

* FORECAST THROUGH MIDNIGHT:
  WIDELY SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP BY MID
  AFTERNOON...AND THEN END BY EARLY EVENING.  THESE STORMS MAY PRODUCE
  LARGE HAIL.

* SIGNIFICANT WEATHER:
  LARGE HAIL...DIME SIZE OR LARGER.

* SPOTTER ACTIVATION:
  SPOTTER ACTIVATION IS POSSIBLE AFTER 4 PM.

SDZ062-066-067-069>071-MNZ071-072-080-089-097-098-IAZ001-012-020-
031-NEZ013-014-290500-
LINCOLN-LYON-PIPESTONE-MURRAY-MINNEHAHA-ROCK-NOBLES-TURNER-LINCOLN-
LYON-YANKTON-CLAY-UNION-SIOUX-PLYMOUTH-DIXON-DAKOTA-WOODBURY-
INCLUDING THE CITIES OF...PIPESTONE...SLAYTON...SIOUX FALLS...LUVERNE...
WORTHINGTON...ROCK RAPIDS...YANKTON...VERMILLION...ELK POINT...
SIOUX CENTER...LE MARS...SIOUX CITY...
1100 AM CDT SUN JUL 28 2002

* FORECAST THROUGH MIDNIGHT:
  NUMEROUS THUNDERSTORMS ARE EXPECTED TO DEVELOP BY MID AFTERNOON...AND
  CONTINUE INTO THE EARLY EVENING HOURS.  THESE STORMS WILL BE CAPABLE
  OF PRODUCING LARGE HAIL AND DAMAGING WINDS.

* SIGNIFICANT WEATHER:
  SEVERE WINDS...GUSTS EQUAL TO OR GREATER THAN 58 MPH.
  LARGE HAIL...DIME SIZE OR LARGER.

* SPOTTER ACTIVATION:
  SPOTTER ACTIVATION IS LIKELY AFTER 4 PM.

MNZ081-090-IAZ002-003-013-014-021-022-032-290500-
COTTONWOOD-JACKSON-OSCEOLA-DICKINSON-OBRIEN-CLAY-CHEROKEE-BUENA VISTA-IDA-
INCLUDING THE CITIES OF...SPIRIT LAKE...SPENCER...STORM LAKE...
1100 AM CDT SUN JUL 28 2002

* FORECAST THROUGH MIDNIGHT:
  NUMEROUS THUNDERSTORMS ARE EXPECTED TO DEVELOP BY MID AFTERNOON...AND
  CONTINUE INTO THE LATE EVENING HOURS.  THESE STORMS WILL BE CAPABLE
  OF PRODUCING LARGE HAIL...DAMAGING WINDS...AND VERY HEAVY RAIN.

* SIGNIFICANT WEATHER:
  SEVERE WINDS...GUSTS EQUAL TO OR GREATER THAN 58 MPH.
  LARGE HAIL...DIME SIZE OR LARGER.
  HEAVY RAIN.

* SPOTTER ACTIVATION:
  SPOTTER ACTIVATION IS LIKELY AFTER 4 PM.

Local storm report, Jul 28, 12:45 PM CDT, 40 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1245 PM CDT SUN JUL 28 2002

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

1235 PM    9 SSE HURON               SD   .75 INCH HAIL
07/28/02   BEADLE                         REPORTED BY STORM
                                          SPOTTER.

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 28, 12:02 PM CDT	Severe Thunderstorm Warning	FSD	Beadle	38 min
Jul 28, 12:57 PM CDT	Severe Thunderstorm Warning	FSD	Beadle, Kingsbury	33 min
Jul 28, 1:23 PM CDT	Tornado Warning	FSD	Kingsbury	37 min
Jul 28, 1:40 PM CDT	Severe Thunderstorm Warning	FSD	Miner	50 min
Jul 28, 1:59 PM CDT	Tornado Warning	FSD	Brookings, Kingsbury	41 min
Jul 28, 2:12 PM CDT	Tornado Warning	FSD	Brookings	48 min
Jul 28, 2:21 PM CDT	Severe Thunderstorm Warning	FSD	Lake, Moody	39 min
Jul 28, 2:48 PM CDT	Severe Thunderstorm Warning	FSD	Lake, Moody	42 min
Jul 28, 2:59 PM CDT	Severe Thunderstorm Warning	FSD	Brookings	31 min
Jul 28, 3:19 PM CDT	Severe Thunderstorm Warning	FSD	Minnehaha	41 min
Jul 28, 3:27 PM CDT	Severe Thunderstorm Warning	FSD	Moody	33 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.