Alert archive / North Dakota / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 217, NWS Grand Forks, ND

August 15, 2002Nelson County, North Dakota

NWS Grand Forks, ND issued this severe thunderstorm warning at Aug 15, 2002, 6:41 PM CDT for Nelson County, North Dakota. It was in force for 34 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: Aug 15, 2002, 6:41 PM CDT (23:41 UTC)
Expired: Aug 15, 2002, 7:15 PM CDT
In force: 34 min
Issued by: NWS Grand Forks, ND
Area: Counties, with a storm outline in the text

County Nelson County, ND

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

Bismarck Municip, ND (KBIS), launched 12:00Z, 11.7 hours before the alert went out and 222 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: 816 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 17 m²/s²
0-3 km storm-relative helicity: 52 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.

628 
WUUS53 KFGF 152341
SVRFAR
NDC063-160015-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
639 PM CDT THU AUG 15 2002

THE NATIONAL WEATHER SERVICE IN GRAND FORKS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...

  CENTRAL NELSON COUNTY IN NORTHEAST NORTH DAKOTA.

* UNTIL 715 PM CDT.

* AT 637 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER STUMP LAKE...OR ABOUT 26 MILES SOUTHEAST
  OF DEVILS LAKE...MOVEMENT WAS TO THE SOUTHEAST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...

  TOLNA AT 640 PM...
  PEKIN AT 650 PM AND
  MCVILLE AT 705 PM.

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

LAT...LON 4802 9845 4782 9849 4770 9812 4803 9794


55

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 15, 2:15 PM CDT, 4 hours 26 minutes earlier.

Area forecast discussion, Aug 15, 2:15 PM CDT, 4 hours 26 minutes before

FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
215 PM CDT THU AUG 15 2002

...MAIN FORECAST CHALLENGE FOCUSES ON LINGERING CONVECTIVE THREAT
THIS EVENING AND THEN NEXT IMPENDING POP/CONVECTIVE EVENT LATE
FRIDAY INTO EARLY SATURDAY...

.CURRENT OBSERVATIONAL OVERVIEW...
18Z MSAS ANALYSIS CONTINUED TO DEPICT LOW PRESSURE OVER ONTARIO
PROVINCE WITH ASSOCIATED COLD FRONT VICINITY OF EASTERN NEBRASKA
WESTERN IOWA BORDER. SECONDARY TROUGH EXTENDING FROM LOW WAS NOTED
FROM NEAR LAKE WINNIPEG TO SOUTHERN SASK PROVINCE. LATEST KMVX RADAR
AND SATELLITE IMAGERY SHOWED COLD POOL ALOFT GENERATED SCATTERED
SHOWER/EMBEDDED THUNDER PERSISTING GENERALLY NORTH OF HIGHWAY 2.
APPEARS MOST CONCENTRATED ACTIVITY IS FIRING JUST NORTH OF 500MB
SHEAR AXIS/AHEAD OF AFOREMENTIONED UPSTREAM SURFACE TROUGH WHERE
MOISTURE FLUX CONVERGENCE IS ENHANCED.

.FORECAST DETAILS...
EXPECT LINGERING COLD POOL ALOFT GENERATED CONVECTION TO BE ON THE
WANE THIS EVENING AS DAYTIME HEATING CEASES. TONIGHT INTO EARLY
FRIDAY WEAK SURFACE RIDGE AND ASSOCIATED SUBSIDENCE BUILDS OVER
REGION WITH CLEAR TO PARTLY CLOUDY SKY COVER. PROGRESSIVE LONGWAVE
PATTERN SHOULD HELP TO ADVECT NEXT UPSTREAM SHORTWAVE TROUGH INTO
REGION LATER FRIDAY AFTERNOON INTO SATURDAY MORNING. EXTRAPOLATION
OF FEATURE SUGGESTS HIGHEST POP THREAT SHOULD ACROSS NORTHERN ZONES
WHERE DEFORMATION ZONE TAKES SHAPE. BEST INSTABILITY PARAMETERS IN
CONJUNCTION WITH SYSTEM SHOULD BE ACROSS THE SOUTH WHERE ACTIVITY
WILL BE MORE SCATTERED IN NATURE AS GOOD DRY PUNCH ROTATES IN.
SATURDAY SHAPING UP AS A WINDY COOL AND UNSETTLED DAY AS FEATURE
BECOMES VERTICALLY STACKED ACROSS ONTARIO PROVINCE RESULTING IN
INCREASING CYCLONIC PRESSURE GRADIENT ACROSS REGION.

.EXTENDED...
LONGWAVE TROUGH TO REMAIN ACROSS CENTRAL CANADA AND THE NORTHERN
PLAINS THROUGH THE PERIOD HOWEVER PATTERN DEAMPLIFIES. SPLIT FLOW
DEVELOPS ACROSS THE REGION FOR THE EXTENDED.  ECMWF IS FASTER THAN
THE MRF EARLY IN THE PERIOD. THE ECMWF BECOMES SLOWER THAN THE MRF
LATE IN THE PERIOD. THE 120 HOUR AVN IS IN GOOD AGREEMENT WITH THE
OLD MRF. THE AVN/MRF OPERATIONAL RUNS ARE IN REASONABLE AGREEMENT
THROUGH DAY 5 WITH THE ENSEMBLE MEAN. AFTER DAY 5 OPERATIONAL RUNS
TREND FASTER THAN THE MEAN. WILL MOVE THE CHANCE OF PRECIPITATION
INTO TUESDAY.

FGF...NONE.

BERG/HOPPES

Nearby

Severe Thunderstorm Warnings in North 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.