Alert archive / Minnesota / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 50, NWS Grand Forks, ND

June 24, 1997Polk County, Minnesota

NWS Grand Forks, ND issued this severe thunderstorm warning at Jun 24, 1997, 12:30 AM CDT for Polk County, Minnesota. It was in force for 30 min. 1 report 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: Jun 24, 1997, 12:30 AM CDT (05:30 UTC)
Expired: Jun 24, 1997, 1:00 AM CDT
In force: 30 min
Issued by: NWS Grand Forks, ND
Area: Whole counties

County Polk County, MN

What was reported inside it

Time	Report	Where	Remark
Jun 24, 12:40 AM CDT	Hail 0.75	Maple Bay, 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.

The watch it was issued in

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

Issued	Product	Office	Lasted
Jun 23, 11:15 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

International Fa, MN (KINL), launched 00:00Z, 5.5 hours before the alert went out and 246 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: 141 J/kg
Mixed-layer CIN: -442 J/kg
Mixed-layer LCL: 601 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 34 m²/s²
0-3 km storm-relative helicity: 180 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.

000 
TTAA00 KFAR 240530 RRA
SVRFAR
MNC119-240600-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
1230 AM CDT TUE JUN 24 1997
 
THE NATIONAL WEATHER SERVICE IN EASTERN ND/GRAND FORKS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  100 AM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN NORTHWEST MINNESOTA
 
   ...SOUTHERN POLK COUNTY
 
AT 1230 AM CDT...DOPPLER WEATHER RADAR INDICATED A SEVERE THUNDERSTORM
30 MILES SOUTH OF THIEF RIVER FALLS...NEAR ERSKINE MOVING EAST AT 25
MPH. TOWNS IN THE PATH INCLUDE ERSKINE...MAKINTOSH AND FOSSTON.
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND OVER 57 MPH...HAIL
3/4 INCH IN DIAMETER OR LARGER...TORNADOES...DEADLY
LIGHTNING...AND VERY HEAVY RAIN.  MOVE TO A SMALL INTERIOR
ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS.
 
RA

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 Jun 23, 8:45 PM CDT, 3 hours 45 minutes earlier.

Area forecast discussion, Jun 23, 8:45 PM CDT, 3 hours 45 minutes before

FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
845 PM CDT MON JUN 23 1997

FIRST PERIOD DISCUSSION...SEVERAL AREAS FOR CONCERN THIS EVENING AS FAR
AS TSRA. BAND OF TSRA IN CENTRAL/WEST ND MOVG NE. EASTERN PTN MOVG INTO
MORE UNSTABLE AIR ACROSS WESTERN CWFA WILL CONTINUED TO BE MONITORED.
MAIN CONCERN IS ACROSS SE ND INTO WEST CENTRAL MN ALONG SFC BOUNDARY.
BIG QUESTION IS WHEN AND IF CAP BREAKS. FAIRLY STRONG MID LEVEL
INVERSION AT BIS...ABR AND INL WITH STRONGEST CAPPING AT INL. H7 TEMPS
AT ABR AND INL APPEAR TO BE AROUND +13. CELLS HAVE BEEN TRYING TO
DEVELOP BETWEEN JMS AND VALLEY CITY LAST HOUR OR SO. IF CELLS BREAK CAP
THEY SHOULD TAKE OFF QUICK AS AREA VERY UNSTABLE WITH ADAP LI'S -10 AND
BEST CONVERGENC. CAPES ALSO RUNNING FROM 2000-3000 J/KG. AM ALSO
CONCERNED ABOUT DEVELOPMENT LATER NORTH OF WARM FRONT THROUGH CENTRAL
MN HOWEVER CAP MAY BE TOO STRONG TO OVERCOME. IF CONVECTION DOES OCCUR
WILL PROBABLY BE LATE.  WITH PWATS >1.25 AND K INDICES FROM 30 TO 36
HEAVY RAIN IS ALSO A CONCERN ESPECIALLY WITH LOCALLY HEAVY AMOUNTS FROM
LAST NIGHT. WILL INCLUDE LCL HEAVY RAIN PSBL IN UPDATE ALONG WITH
SEVERE. WITH SFC BOUNDARY NOT PROGGED TO MOVE AND CURRENT TD'S IN MID
TO UPPER 60S...MAY HAVE TO NUDGE UP MINS SLIGHTLY ACROSS SOME AREAS
WILL TAKE LAST MINUTE LOOK.
VOELKER

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 23, 10:45 PM CDT	Severe Thunderstorm Warning	FGF	Polk	30 min
Jun 23, 11:34 PM CDT	Severe Thunderstorm Warning	FGF	Polk	26 min
Jun 24, 12:04 AM CDT	Severe Thunderstorm Warning	FGF	Polk	26 min
Jun 24, 4:34 AM CDT	Flash Flood Warning	FGF	Clearwater, Polk	3 hr

Nearby

Severe Thunderstorm Warnings in Minnesota, 1997 Every severe thunderstorm warning in 1997

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.