Alert archive / North Dakota / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 319, NWS Grand Forks, ND

August 31, 2002Cavalier County, North Dakota

NWS Grand Forks, ND issued this severe thunderstorm warning at Aug 31, 2002, 8:32 PM CDT for Cavalier County, North Dakota. It was in force for 43 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 31, 2002, 8:32 PM CDT (01:32 UTC)
Expired
Aug 31, 2002, 9:15 PM CDT
In force
43 min
Issued by
NWS Grand Forks, ND
Area
Counties, with a storm outline in the text

County Cavalier County, ND

The radar

The Fargo/Grand Forks radar (KMVX), 142 km from the middle of the area, began a volume at 01:33 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 was reported inside it

TimeReportWhereRemark
Aug 31, 8:43 PM CDTHail 0.88Osnabrock, ND
Aug 31, 9:25 PM CDTHail 1Olga, ND

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.

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 watch it was issued in

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

IssuedProductOfficeLasted
Aug 31, 7:00 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 00:00Z, 1.5 hours before the alert went out and 285 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 2002-09-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1564 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 2002-09-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 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
1564 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
2744 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
57 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.1

Open this sounding in Storm Lab

The text

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

393 
WUUS53 KFGF 010132
SVRFAR
NDC019-010215-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
831 PM CDT SAT AUG 31 2002

THE NATIONAL WEATHER SERVICE IN GRAND FORKS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...

  EASTERN CAVALIER COUNTY IN NORTHEAST NORTH DAKOTA.

* UNTIL 915 PM CDT.

* AT 828 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 4 MILES SOUTHWEST OF OSNABROCK...OR ABOUT 12
  MILES SOUTHEAST OF LANGDON...MOVEMENT WAS TO THE NORTHEAST AT 55
  MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...

  MILTON AT 835 PM AND
  OLGA AT 840 PM.

REMEMBER SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE
TORNADOES WITH LITTLE OR NO ADVANCE WARNING.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL MIDNIGHT SUNDAY
MORNING FOR NORTHWEST MINNESOTA AND NORTHEAST NORTH DAKOTA. A SEVERE
THUNDERSTORM WATCH ALSO REMAINS IN EFFECT UNTIL MIDNIGHT SUNDAY
MORNING FOR NORTHEAST NORTH DAKOTA.

LAT...LON 4869 9833 4853 9820 4859 9796 4891 9796


04

NNNN

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 Grand Forks, ND wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 31, 1:57 PM CDT, 6 hours 35 minutes earlier.

Area forecast discussion, Aug 31, 1:57 PM CDT, 6 hours 35 minutes before
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
157 PM CDT SAT AUG 31 2002

...FORECAST CHALLENGE WILL BE HEAVY RAIN POTENTIAL TONIGHT AND EARLY
SUNDAY...

.CURRENT OBSERVATIONS...
BEST SURFACE CONVERGENCE AND PRESSURE FALLS OCCURRING ACROSS
SOUTHWEST NORTH DAKOTA. AS PREVIOUSLY THOUGHT...DEWPOINTS ARE HIGHER
THAN MODEL GUIDANCE WITH MANY AREAS NEAR 70 DEGREES.

.SHORT TERM...
EXPECT THE FORECAST AREA(FA) TO BECOME VERY ACTIVE THIS EVENING AS
SURFACE FRONT ARRIVES ALONG WITH POTENT SHORT WAVE. AVN/ETA IN GOOD
AGREEMENT BRINGING PRECIPITABLE WATERS OF NEARLY 2 INCHES ACROSS
PORTIONS OF CWA. 850MB 40 KT LLJ AND WARM AIR ADVECTION POINT TO THE
BEST ORGANIZED STORM POTENTIAL ACROSS THE SOUTHEASTERN HALF OF THE
FA WITH LEAST POTENTIAL ACROSS THE DEVILS LAKE REGION. WITH NUMEROUS
REGIONS RECEIVING HEAVY RAINFALL OVER THE PAST SEVERAL DAYS...WILL
ISSUE A FLOOD WATCH FOR TONIGHT FOR ENTIRE FA AND HIGHLIGHT THE
SOUTHEASTERN HALF.

.MID TERM...
MOST OF SUNDAY WILL BE QUIET BEFORE THE NEXT FRONT AND WAVE COMES
DOWN SUNDAY NIGHT AND MONDAY. EXPECT SCATTERED THUNDERSTORMS WITH
THIS SYSTEM BUT IT WILL HAVE A MUCH DRIER ENVIRONMENT TO WORK WITH.
HIGH PRESSURE BUILDS IN MONDAY AFTERNOON AND TUESDAY BRINGING A LULL
IN THE ACTIVITY.

.EXTENDED...
NEW MRF/AVN LINING UP WITH OTHER EXTENDED RUNS IN MAINTAINING
TROUGHING OVER WEST COAST VS MORE PROGRESSIVE SOLUTION OF PREVIOUS
DAY. AS A RESULT REGION GOES BACK INTO SW FLOW ALOFT OVER SECOND
HALF OF WORK WEEK AND INTO NEXT WEEKEND. SFC LOW REORGANIZES OVER
WESTERN HIGH PLAINS WITH PIECES OF ENERGY BEING EJECTED FROM PARENT
LOW OVER PACIFIC NW. FAVORED CHANCES FOR PCPN LOOK TO BE THURSDAY
THROUGH EARLY SATURDAY AS FEATURES SHIFT EAST. BASED ON POSITION OF
850MB THERMAL RIDGE AND THICKNESS TEMPS SHOULD BE AT OR ABOVE
SEASONAL AVERAGES UNTIL FROPA FRIDAY NIGHT.

THANKS FOR COORDINATION...MSP...DLH...ABR...BIS

.FGF...FLASH FLOOD WATCH ENTIRE CWA TONIGHT

DONAVON/VOELKER

In the hours before

Local storm report, Aug 31, 3:43 PM CDT, 4 hours 49 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS, ND
343 PM CDT SAT AUG 31 2002

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

0745 AM    8 N BEMIDJI               MN   .75 INCH HAIL
08/31/02   BELTRAMI

The office that day

Everything else NWS Grand Forks, ND issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 31, 7:13 PM CDTSevere Thunderstorm WarningFGFCavalier47 min
Aug 31, 7:22 PM CDTFlash Flood WarningFGFCavalier4 hr
Aug 31, 7:45 PM CDTSevere Thunderstorm WarningFGFPembina45 min
Aug 31, 7:56 PM CDTSevere Thunderstorm WarningFGFCavalier34 min
Aug 31, 8:42 PM CDTTornado WarningFGFCavalier33 min
Aug 31, 8:53 PM CDTSevere Thunderstorm WarningFGFPembina52 min
Aug 31, 9:00 PM CDTSevere Thunderstorm WarningFGFBenson, Towner45 min
Aug 31, 9:11 PM CDTSevere Thunderstorm WarningFGFCavalier49 min
Aug 31, 9:43 PM CDTSevere Thunderstorm WarningFGFBenson, Ramsey, Towner62 min
Aug 31, 9:47 PM CDTSevere Thunderstorm WarningFGFPembina43 min
Aug 31, 10:02 PM CDTSevere Thunderstorm WarningFGFCavalier43 min
Aug 31, 10:07 PM CDTFlash Flood WarningFGFCavalier, Pembina3 hr
Aug 31, 10:20 PM CDTSevere Thunderstorm WarningFGFBarnes, Griggs55 min
Aug 31, 10:30 PM CDTSevere Thunderstorm WarningFGFPembina45 min
Aug 31, 10:45 PM CDTSevere Thunderstorm WarningFGFCavalier45 min
Aug 31, 10:52 PM CDTSevere Thunderstorm WarningFGFCass53 min
Aug 31, 11:15 PM CDTSevere Thunderstorm WarningFGFBarnes30 min
Aug 31, 11:18 PM CDTSevere Thunderstorm WarningFGFPembina42 min
Sep 1, 12:28 AM CDTSevere Thunderstorm WarningFGFSargent47 min
Sep 1, 1:19 AM CDTSevere Thunderstorm WarningFGFRichland41 min

Nearby

Severe Thunderstorm Warnings in North Dakota, 2002Every 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; radar from the NEXRAD Level II archive.