486
FXUS63 KFGF 111129
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
629 AM CDT Mon Aug 11 2025

.KEY MESSAGES...

- Wildfire smoke will impact air quality and visibility across
  much of the area today.

- There is a 1 of 5 risk for severe thunderstorms this
  afternoon and evening. Hazards could include damaging wind
  gusts to 60 mph and hail up to 1 inch in diameter. An isolated
  brief tornado cannot be ruled out.

- There is a 1 of 5 risk for severe thunderstorms Wednesday
  evening, with additional severe thunderstorms possible
  Thursday afternoon.

&&

.UPDATE...
Issued at 629 AM CDT Mon Aug 11 2025

Near surface wildfire smoke continues to impact visibility this
morning, with visibility generally ranging from 2-5 miles
across much of the area. HRRR smoke guidance keeps wildfire
smoke in the area through much of the morning and early
afternoon before clearing becomes possible during the evening.
This will depend upon the timing of an approaching cold front,
with winds expected to shift to the west.

&&

.DISCUSSION...
Issued at 353 AM CDT Mon Aug 11 2025

...Synopsis...

H5 trough moves across the area today, along with a cold frontal
passage this afternoon. Showers and thunderstorms are possible this
afternoon and evening, with the potential for strong to severe
storms. Near surface smoke is expected to persist through much of
the day and into the evening until the cold front moves through the
area. Look for cooler high temperatures in the 70s Tuesday, along
with breezy northwest winds. A shortwave ridge forms ahead of our
next shortwave passage late Tuesday into Wednesday. Showers and
thunderstorms are expected along and ahead of a surface boundary
Wednesday evening and overnight into Thursday morning. Strong to
severe storms are possible across portions of southeastern North
Dakota Wednesday evening, then once more on Thursday as the boundary
progresses eastward.

...Severe Thunderstorms Possible This Afternoon and Evening...

Showers and thunderstorms are possible starting around midday with
strong to severe storms possible during the afternoon and evening.
There will be limited instability as MLCAPE values struggle to
exceed 2000 J/Kg as moisture pools ahead of a theta-e gradient
boundary. The boundary will serve as a potential axis of
development, providing enough lift to allow clusters of
thunderstorms to form. Shear profiles support the mention of
supercells or hybrid clusters during the mid to late afternoon, with
this support extending into the early evening. Soundings indicate a
shallow layer of relatively dry air at the surface, along with DCAPE
values generally in the range of 700 to 900 J/Kg. If a supercell is
able to form, hodographs support splitting, with right-moving storms
potentially capable of producing brief tornadoes. Hazards this
afternoon and evening could include damaging wind gusts to 60 mph,
brief tornadoes, and hail up to 1 inch in diameter.

...Severe Thunderstorm Risk Wednesday and Thursday...

Moisture levels gradually increase Wednesday, with conditional
chances for severe storms Wednesday evening through Thursday
morning. Instability will be minimal across much of the area, with
mainly the southeast corner of North Dakota seeing the chance to
reach 1500 J/Kg of MUCAPE ahead of the approaching H5 shortwave.
Heading into Thursday, additional thunderstorm activity will have
access to an increasingly unstable atmosphere, with MUCAPE
approaching 3000-4000 J/Kg and deep layer shear upwards of 45 knots.
The aforementioned shortwave will continue eastward, providing lift
to the region along one of several theta-e axes. Exact timing
remains uncertain at this time; however, confidence is increasing
regarding the potential for severe thunderstorms.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 629 AM CDT Mon Aug 11 2025

MVFR conditions prevail across most of the region this morning
with occasional IFR visibility being reported at KGFK and KTVF.
Visibility at most sites across the area ranges from 2-5SM. While
some improvement is possible, near term guidance holds onto
near surface wildfire smoke through much of the day before
clearing this evening and overnight. Scattered showers and
thunderstorms are expected this afternoon, with the potential
for strong to severe thunderstorms ahead of an approaching cold
front. Southwest winds shift as the front moves through,
becoming northwesterly this evening. Winds will be in the range
of 10 to 15 knots this afternoon, with gusts upwards of 20
knots.

&&

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

&&

$$

UPDATE...Lynch
DISCUSSION...Lynch
AVIATION...Lynch