Alert archive / Minnesota / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 136, NWS Grand Forks, ND

July 25, 1997Roseau County, Minnesota

NWS Grand Forks, ND issued this severe thunderstorm warning at Jul 25, 1997, 6:35 PM CDT for Roseau County, Minnesota. It was in force for 25 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: Jul 25, 1997, 6:35 PM CDT (23:35 UTC)
Expired: Jul 25, 1997, 7:00 PM CDT
In force: 25 min
Issued by: NWS Grand Forks, ND
Area: Whole counties

County Roseau County, MN

The radar

The Fargo/Grand Forks radar (KMVX), 178 km from the middle of the area, began a volume at 23:38 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
Jul 25, 7:00 PM CDT	Thunderstorm Wind	Roseau, MN	Wind blew down trees north of Roseau.

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
Jul 25, 4:45 PM CDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 12:00Z, 11.6 hours before the alert went out and 428 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: 655 J/kg
Mixed-layer CIN: -252 J/kg
Mixed-layer LCL: 1262 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 35 m²/s²
0-3 km storm-relative helicity: 42 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 Jul 25, 2:56 PM CDT, 3 hours 39 minutes earlier.

Area forecast discussion, Jul 25, 2:56 PM CDT, 3 hours 39 minutes before

FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
255 PM CDT FRI JUL 25 1997

PROBLEM FOR FIRST PERIOD IS PCPN. TSRA ALREADY IN WESTERN PART OF CWFA
MOVINMG NE WITH KMVX 88D ESTIMATING 1.4 INCHES IN SOUTHERN BENSON
COUNTY. 18Z SFC ANALYSIS HAS STATIONARY FRONT SLIGHTLY FURTHER EAST
WITH NUMEROUS LEFTOVER BOUNDARIES. NGM CONTINUES TO HAVE THE BEST
HANDLE ON SITUATION WITH UPPER LEVEL DIVERGENCE AND NE-SW ORIENTED
THETA-E RIDGE. LOOKS LIKE BEST CHANCE FOR SEVERE WEATHER IS IN THE DVL
AREA. THE POTENTIAL FOR HEAVY RAIN IS ALSO A GOOD POSSIBILITY. FLASH
FLOOD GUIDANCE IN DVL AREA RANGES FROM 1 INCH TO UNDER 2 INCHES IN THREE
HOURS. SUGGEST STRONGLY CONSIDER FLASH FLOOD WATCH FOR DVL AREA.

SUGGESTIONS:
DVL/NELSON/GRIGGS/BARNES...GOOD CHANCE OF THUNDERSTORMS...POSSIBLY
SEVERE WITH HEAVY RAIN. LOW NEAR 65.
GFK/FAR...A 40 PERCENT CHANCE OF THUNDERSTORMS. LOW OF 65 TO 70.
ROX/TVF/BJI...A 40 PERCENT CHANCE OF THUNDERSTORMS. LOW OF 65 TO 70.
DTL/FFM...A 30 PERCENT CHANCE OF THUNDERSTORMS. LOW IN THE UPPER 60S.

GSF

In the hours before

Special weather statement, Jul 25, 12:44 PM CDT, 5 hours 51 minutes before

MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052-053-261200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
1244 PM CDT FRI JUL 25 1997

...THERE IS A SLIGHT RISK FOR SEVERE WEATHER OVER EASTERN NORTH DAKOTA
LATE THIS AFTERNOON AND EVENING...

AS IN THE PAST SEVERAL DAYS VERY WARM...MOIST AND UNSTABLE AIR WILL
CONTINUE ACROSS THE REGION AS AN AREA OF LOW PRESSURE OVER THE NORTHERN
PLAINS REMAINS STATIONARY.

WHILE THE POSSIBILITY EXISTS FOR THUNDERSTORM DEVELOPMENT ANYWHERE IN
THIS UNSTABLE AIR MASS IT APPEARS THAT THE BEST AREAS FOR SEVERE
WEATHER WILL BE ACROSS NORTHEAST NORTH DAKOTA. THIS AREA INCLUDES THE
DEVILS LAKE...CANDO AND NEW ROCKFORD AREAS. THESE STORMS COULD THEN
THEN AFFECT THE LANGDON...CAVALIER...PARK RIVER AND GRAND FORKS AREAS
LATER THIS EVENING. PRIMARY CONCERN WOULD BE DAMAGING WINDS AND LARGE
HAIL. WITH HIGH LEVELS OF MOISTURE IN THE ATMOSPHERE...VERY HEAVY RAINS
ARE ALSO A POSSIBILITY.

GSF

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 24, 8:55 PM CDT	Severe Thunderstorm Warning	FGF	Towner	35 min
Jul 25, 12:32 AM CDT	Severe Thunderstorm Warning	FGF	Benson	28 min
Jul 25, 4:28 PM CDT	Severe Thunderstorm Warning	FGF	Cavalier	32 min
Jul 25, 5:27 PM CDT	Tornado Warning	FGF	Walsh	33 min
Jul 25, 6:00 PM CDT	Tornado Warning	FGF	Walsh	30 min
Jul 25, 6:26 PM CDT	Severe Thunderstorm Warning	FGF	Sargent	34 min
Jul 25, 6:45 PM CDT	Flash Flood Warning	FGF	Walsh	2 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; radar from the NEXRAD Level II archive.