056
FXUS63 KFGF 111750
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
1250 PM 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 1250 PM CDT Mon Aug 11 2025

Forecast remains on track, adjusted sky cover this afternoon a
bit, otherwise frontal boundary in the northwest to drop
southeast with shower/storm development along the boundary
toward late afternoon/evening as the front progresses southeast.
Higher level smoke still dropping visibilities across the area
to around 2-4 miles in spots.

Previous 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 /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1250 PM CDT Mon Aug 11 2025

South to southwesterly flow ahead of a cold front with winds to
shift to the west to northwest behind the front. Tried to time
best chances for showers or thunderstorms with the front. Best
chances for storms in the eastern terminal locations this
evening. Winds to increase some this afternoon and again late
Tuesday morning. Could see some lower clouds linger into Tuesday
morning behind the front at KBJI. Vsbys remain lower with the
wildfire smoke in the area ahead of the front, and expect the
smoke to clear out with any rain/frontal passage.

&&

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

&&

$$

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