Grand Forks AFB, North Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

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FXUS63 KFGF 201744
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
1244 PM CDT Sun Jul 20 2025

.KEY MESSAGES...

- Severe storms developing over south central North Dakota will
  push into eastern North Dakota late Sunday. There is a level
  1 out of 5 risk of severe thunderstorms across much of eastern
  North Dakota and west central Minnesota.

- Smoke from Canadian wildfires will degrade air quality
  through Monday.

- There is a level 1 out of 5 risk for severe storms both Monday
  and Tuesday.

&&

.UPDATE...
Issued at 1244 PM CDT Sun Jul 20 2025

Complex of showers and thunderstorms riding along the ND/SD
border is now approaching our southwestern counties. There is
not much MU CAPE to work with as it moves east, so think there
will continue to be a weakening trend. Better chances later
tonight as elevated CAPE increases. Some areas of smoke mainly
over northwestern MN are dropping vis down to 4 or 5 miles at
times, but should get shifted back to the north later tonight as
winds come around to the southeast.

UPDATE
Issued at 956 AM CDT Sun Jul 20 2025

Adjusted POPs a bit for the showers moving in from the west.
Still a weakening trend this morning as the activity is moving
into areas with very little instability. Better chances for
storms later this evening.

UPDATE
Issued at 626 AM CDT Sun Jul 20 2025

Light showers continue to work across the area this morning,
mainly along and north of Highway 200. This activity is
gradually weakening as it moves slowly to the east. Made slight
adjustments to PoP timing, with the forecast remaining
otherwise on track.

&&

.DISCUSSION...
Issued at 350 AM CDT Sun Jul 20 2025

...Synopsis...

Progressive H5 flow continues across the northern CONUS through
early next week before a more southwesterly trend begins. Shortwaves
will traverse the H7 flow pattern, bringing continued chances for
showers and thunderstorms today through Tuesday. Heading into
Wednesday, ridging strengthens slightly over the Mississippi and
Ohio River Valley, with weak troughing developing across the western
CONUS. This will allow a slightly more southwesterly flow pattern
across the Central and Northern Plains heading into Thursday and
Friday.

...Isolated Severe Thunderstorms Possible Today...

CAMs continue to produce convection this afternoon across central
North Dakota, which then progresses eastward through the late
afternoon and evening hours. The environment will be increasingly
capped as these storms push into eastern North Dakota, mainly due to
a rather warm layer of air between 850 and 700 mb. Above this layer,
instability is supportive of strong to severe thunderstorm
development, meaning we could see elevated storms capable of large
hail late this evening and into the early overnight period.

...Wildfire Smoke Today...

Smoke has worked southward into northwest Minnesota and northeast
North Dakota this morning. The highest concentrations of smoke
remain in southeastern Manitoba and southern Ontario; however, the
trend brings these higher concentrations slightly further south by
midday today.

...Severe T-Storms Possible Mon and Tue...

Monday: Conditions become increasingly supportive of strong to
severe thunderstorms Monday and Tuesday. Cooler air at the 700mb
level will improve lapse rates and reduce capping Monday afternoon
and evening. Model soundings indicate MLCAPE upwards of 3000 J/Kg
Monday afternoon, with 0-6 km shear in the 45-50 knot range. The low
to mid level shear will be favorable for the development of
supercells and hybrid clusters, especially for southeastern North
Dakota, southern Red River Valley, and west central Minnesota.
Further north, clusters will be the most likely mode across
northeast North Dakota, northern Red River Valley, and northwest
Minnesota.

Tuesday: A shortwave will traverse the region on Tuesday, with
instability building in the pre-trough environment. Soundings still
show a strong rebound of MLCAPE values by midday Tuesday, which
could approach 3500 J/Kg. Shear remains supportive of supercells at
both the mid and upper levels, with all hazards possible as a
result.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1244 PM CDT Sun Jul 20 2025

A mix of light rain showers and, at KGFK and the MN airports at
least, surface smoke reducing visibility to 4-5SM at times.
Thunderstorms just west of our forecast area should weaken as
they move east, leaving mostly showers and the smoke continuing
into the evening. Some better thunderstorm chances later
tonight, but not confident enough to include in the TAFs.
Ceilings are mostly VFR and will remain so through most of the
afternoon and evening, with some MVFR ceilings coming in towards
Monday morning. Winds will continue out of the southeast mainly
at 5 to 15 kts, but some gusts to around 20 kts are possible
this afternoon or towards the end of the period.

&&

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

&&

$$

UPDATE...Lynch/JR
DISCUSSION...Lynch
AVIATION...JR