Alert archive / Minnesota / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 12, NWS Grand Forks, ND

April 23, 2002Marshall County, Minnesota

NWS Grand Forks, ND issued this severe thunderstorm warning at Apr 23, 2002, 9:49 PM CDT for Marshall County, Minnesota. It was in force for 41 min. 1 report 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: Apr 23, 2002, 9:49 PM CDT (02:49 UTC)
Expired: Apr 23, 2002, 10:30 PM CDT
In force: 41 min
Issued by: NWS Grand Forks, ND
Area: Counties, with a storm outline in the text

County Marshall County, MN

The radar

The Fargo/Grand Forks radar (KMVX), 104 km from the middle of the area, began a volume at 02:51 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

Time	Report	Where	Remark
Apr 23, 10:01 PM CDT	Hail 0.75	Newfolden, MN

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 nearest sounding before it

International Fa, MN (KINL), launched 00:00Z, 2.8 hours before the alert went out and 239 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: 47 J/kg
Mixed-layer CIN: -87 J/kg
Mixed-layer LCL: 1705 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 72 m²/s²
0-3 km storm-relative helicity: 102 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.

287 
WUUS53 KFGF 240249
SVRFAR
MNC089-240330-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
949 PM CDT TUE APR 23 2002

THE NATIONAL WEATHER SERVICE IN GRAND FORKS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...

  CENTRAL MARSHALL COUNTY IN NORTHWEST MINNESOTA.

* UNTIL 1030 PM CDT.

* AT 946 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 5 MILES NORTHWEST OF VIKING...OR ABOUT 13 MILES
  EAST OF WARREN...MOVEMENT WAS TO THE NORTHEAST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...

  NEWFOLDEN AT 1010 PM.

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

LAT...LON 4821 9677 4819 9645 4833 9619 4851 9641


8

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 Apr 23, 8:50 PM CDT, 59 minutes earlier.

Area forecast discussion, Apr 23, 8:50 PM CDT, 59 minutes before

FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
850 PM CDT TUE APR 23 2002

FORECAST CHALLENGES MANY HOWEVER MAIN CONCERN IS ONGOING WINTER
STORM HEADLINES.

CONVECTION WITH ISOLD SVR CONTINUES TO FIRE AHEAD OF STRONG COLD
FRONT/SFC LOW ORIENTED FROM NORTHERN RED RIVER VALLEY TO EAST OF
JMS. FARTHER WEST BAND OF -RA WORKING ACROSS CENTRAL ND. INITIAL
WAVE FROM WATER VAPOR LIFTING NORTHEAST WITH SECONDARY SHORT WAVE
PUSHING INTO NW ND.

CONCERN IS WHAT TO DO WITH WATCH WHICH IS IN EFFECT FOR
TONIGHT...18Z MESO ETA...18Z AVN AND LATEST RUC ARE ALL FOCUSING
MAIN PRECIPITATION EVENT ALONG 850MB BAROCLINIC ZONE ALONG AND AHEAD
OF COLD FRONT LIFTING NORTHEAST OVERNIGHT. AT THIS POINT IN TIME IT
SEEMS TO BE THE CASE WITH WHAT IS GOING ON HERE AND UPSTREAM. ALL OF
THESE MODELS SO FAR DOING A GOOD JOB AS 850MB ZERO LINE JUST
ENTERING THE NW CORNER OF ND FROM RUC ANALYSIS. BASED ON POSIT OF
850MB TEMPS AND CRITICAL THICKNESS MAIN PCPN SHIELD EXITS FA BEFORE
VALUES DROP ENOUGH FOR SIGNIFICANT SNOWFALL. BEST AREA FOR ANY
ACCUMULATIONS LOOKS TO BE OVER FAR NORTHEAST COUNTIES WHERE AN INCH
OR TWO MAY BE POSSIBLE. ELSEWHERE WITH SFC TEMPERATURES STILL ABOVE
FREEZING INTO SOUTHERN SASKATCHEWAN FEEL SNOWFALL WILL NOT BE
INTENSE ENOUGH FOR SIGNIFICANT ACCUMULATIONS. AS A RESULT BASED ON
AVAILABLE INFO HAVE NO CHOICE BUT TO DROP WATCH. WILL HOWEVER NEED
TO ISSUE WIND ADVISORY FOR LATE TONIGHT AND WEDNESDAY BASED ON
ADIABATIC LAYER AND EVOLVING UNIDIRECTIONAL FLOW WITH 30 TO 40KTS
FROM MESO-ETA SOUNDING AND STRONG COLD ADVECTION/ISENTROPIC DESCENT.

.FGF...WINTER STORM WATCH CANCELLED. WIND ADVISORY ENTIRE FORECAST
AREA LATE TONIGHT AND WEDNESDAY.

VOELKER

In the hours before

Local storm report, Apr 23, 8:38 PM CDT, 1 hour 11 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS, ND
838 PM CDT TUE APR 23 2002

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

0805 PM    6 N CROOKSTON             MN   .75 INCH HAIL
04/23/02   POLK

0824 PM    DOROTHY                   MN   1.00 INCH HAIL
04/23/02   RED LAKE

BRAMER

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 23, 7:32 PM CDT	Severe Thunderstorm Warning	FGF	Polk	43 min
Apr 23, 8:04 PM CDT	Severe Thunderstorm Warning	FGF	Pennington, Red Lake	41 min
Apr 23, 8:42 PM CDT	Severe Thunderstorm Warning	FGF	Marshall, Pennington	48 min
Apr 23, 11:36 PM CDT	Severe Thunderstorm Warning	FGF	Clay, Norman	39 min
Apr 24, 12:34 AM CDT	Severe Thunderstorm Warning	FGF	Polk	26 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 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; radar from the NEXRAD Level II archive.