Severe Thunderstorm Warning 165, NWS Grand Forks, ND

Area Forecast Discussion
National Weather Service Grand Forks ND
620 PM CDT Thu Aug 14 2025

.KEY MESSAGES...

- There is a 2 of 5 risk for severe thunderstorms late this
  afternoon and evening. Hazards could include large hail up to
  the size of tennis balls, damaging wind gusts up to 70mph, and
  isolated tornadoes.

- There is a level 1 out of 5 risk for severe thunderstorms Friday
  afternoon within southeast North Dakota into west- central
  Minnesota.

&&

.UPDATE...
Issued at 620 PM CDT Thu Aug 14 2025

While storms are still expected for at least portions of
northwest Minnesota this evening, storms elsewhere are less
certain and initiation before 9pm in our area is optimistic at
best. CAMS still seem to favor a more cluster/liner moder
overall with a brief window for discrete storms which could
produce hail upwards of 2". Storm timing looks to be 9pm onwards
with back building storms along and south of I94/HWY10 through
the later part of the night.

&&

.DISCUSSION...
Issued at 1257 PM CDT Thu Aug 14 2025

...Synopsis...

The upper air flow pattern will be characterized by zonal flow
for the first few days of the period, transitioning it large
scale ridging by the end of the weekend. This will allow for
periodic chances for showers and thunderstorms through the
weekend, with the greatest risk this afternoon, particularly for
severe thunderstorms.

Signals for late next week show at least some breakdown of the
upper ridge which would bring the chance for additional showers
and thunderstorms, some potentially strong to severe. Time of
year and distance from the predictability horizon precludes any
potential details at this time.

...SEVERE STORMS TODAY...

Surface analysis at 18z indicates a surface low over central
Manitoba with a pressure trough stretching down through the
Devils Lake and James River basins. A tight theta-e gradient
sits behind the trough, which is likely going to be the focal
point for showers and thunderstorms this afternoon.

Capping is likely to limit convective potential, but soundings
right now from the RAP13 indicate a loaded gun with an
absolutely unstable elevated mixed layer. It seems likely that
at least some convection is going to form this afternoon, the
main question is what is the scope.

Should storms form, they will likely become supercells capable
of significant hail exceeding two inches. Straight hodographs
aloft also favor some potential splitting storms which could
inhibit hail production pushing towards higher bounds, but that
will depend on the scope of convective coverage. With the very
high DCAPE, severe wind is possible with any RFD punches.
Tornado potential should be heavily mitigated by low wet bulb
temperatures and high DCAPE. Having said that, surface vorticity
does exist so tornadoes cannot be ruled out. Storms should
diminish after sunset for the most part thanks to the strongest
forcing being near the surface, however the existence of a
residual EML could potentially create brief additional
convection overnight. The probability for this is low as the
low-level jet is displaced to the east, but it cannot be ruled
out for some elevated hail potential overnight from a cold front
aloft that provides just enough nudge.

...SEVERE STORMS TOMORROW...

As the front sags southward overnight, dewpoints will continue
to linger behind the front, around the 60s and 70s. This means
instability will stick around in the southern half of our CWA,
however forcing is very limited so confidence is low on
potential convection tomorrow afternoon. If thunderstorms form,
the general threat at this time should be 60-70 mph winds with
1.5 inch hail. Shear is much more limited as the main jet will
constrain to Canada.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 620 PM CDT Thu Aug 14 2025

Thunderstorms tonight will create local MVFR from 02z until the
dawn hours before waning otherwise VFR skies with winds on the
lighter side (5-10 kts). Will amend timing for storms at taf
sites once we see initiation otherwise plan on a thunder fill
night for TVF and BJI.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.

&&

UPDATE...TT
DISCUSSION...Perroux
AVIATION...TT

Hazardous Weather Outlook
National Weather Service Grand Forks ND
958 AM CDT Thu Aug 14 2025

MNZ001-002-004>009-013>017-022-023-NDZ006>008-014>016-024-026>030-
038-039-054-151500-
West Polk-Norman-Kittson-Roseau-Lake Of The Woods-West Marshall-
East Marshall-North Beltrami-Pennington-Red Lake-East Polk-
North Clearwater-South Beltrami-Mahnomen-South Clearwater-Towner-
Cavalier-Pembina-Benson-Ramsey-Eastern Walsh-Eddy-Nelson-
Grand Forks-Griggs-Steele-Traill-Barnes-Cass-Western Walsh-
958 AM CDT Thu Aug 14 2025

This hazardous weather outlook is for portions of eastern North
Dakota and northwest Minnesota.

.DAY ONE...Today and Tonight

There is a level 2 out of 5 risk for severe thunderstorms late
afternoon into evening. The main hazards will be hail up to the
size of tennis balls, gusts to 70 mph, and possibly a couple
tornadoes. There remains uncertainty on coverage and timing of
storms.

General storm motion...Moving toward the east at 20 mph.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be required today.

MNZ003-024-027>032-040-NDZ049-052-053-151500-
Clay-Hubbard-West Becker-East Becker-Wilkin-West Otter Tail-
East Otter Tail-Wadena-Grant-Ransom-Sargent-Richland-
958 AM CDT Thu Aug 14 2025

This hazardous weather outlook is for portions of eastern North
Dakota, west central and northwest Minnesota.

.DAY ONE...Today and Tonight

There is a level 2 out of 5 risk for severe thunderstorms late
afternoon into evening. The main hazards will be hail up to the
size of tennis balls, gusts to 70 mph, and possibly a couple
tornadoes. There remains uncertainty on coverage and timing of
storms.

General storm motion...Moving toward the east at 20 mph.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

There is a level 1 out of 5 risk for severe thunderstorms Friday
afternoon within southeast North Dakota into west- central
Minnesota.

There is a low chance for strong thunderstorms Saturday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be required today.

Preliminary Local Storm Report
National Weather Service Grand Forks ND
347 PM CDT Thu Aug 14 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0304 AM     Tornado          3 ENE Revere            47.37N 98.26W
08/08/2025                   Griggs             ND   NWS Storm Survey

            This EF1 tornado move northeast across a
            wheat field and then destroyed a pole barn
            during its roughly 1 mile long path. Time
            from barn video.

0348 AM     Tornado          1 WSW Mccanna           48.00N 97.74W
08/08/2025                   Grand Forks        ND   NWS Storm Survey

            This EF1 tornado likely intermittent and
            rain wrapped destroyed 2 grain bins and
            produced shelterbelt tree damage along its
            nearly 3 mile long path with peak wind
            speeds estimated around 105mph.

0351 AM     Tornado          4 E Kempton             47.81N 97.53W
08/08/2025                   Grand Forks        ND   NWS Storm Survey

            EF1 tornado tracked roughly west to east for
            almost 3 miles damaging shelterbelts, 2
            pivot irrigation systems and some crop
            damage.

&&