357
FXUS63 KFGF 101857
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
157 PM CDT Wed Sep 10 2025

.KEY MESSAGES...

- There is a level 1 out of 5 risk for severe thunderstorms
  late Thursday into Thursday night across northeastern ND and
  far northwestern MN.

&&

.DISCUSSION...
Issued at 157 PM CDT Wed Sep 10 2025

...Synopsis...

Upper level flow is characterized by ridging over the central US,
with a large low over California and Oregon. This large area of low
pressure will be the epicenter for waves to emanate from,
propagating across the Northern Plains and Upper Midwest late this
week into the weekend.

In the short term, another night of light winds and clear skies
should promote at least some patchy radiational fog. Thinking areas
in the trees of west central MN are most favored at this time with
winds a bit lighter there and more boundary layer moisture present
as shown by current dew points. Any fog that forms should burn off
mid to late Thursday morning.

...Thunderstorm Potential Thursday and Beyond...

A 40 knot low level jet will develop tonight, more so west of
our FA initially, slowly meandering east with time. By Thursday
evening into the overnight period, this jet will be centered
over the eastern half of ND, advecting moisture and instability
northward. This in turn should foster thunderstorm development
on its northern nose. Where this sets up is uncertain. Some CAMs
push it a little further north into southern Manitoba, leaving
our area drier. Others have the nose of the jet hugging the
International border or just to the south, which would bring
much more activity into our FA. Environmentally, ample effective
shear of 25 to 35 knots, along with instability approaching
2000 J/Kg near the nose of the jet should be more then
sufficient for strong to isolated severe thunderstorm
development. Being elevated in nature, the main threat with
these thunderstorms will be severe hail with any stronger cores
embedded within the cluster. While thunderstorms may develop on
and off on the nose of the jet throughout Thursday, the
strongest storms with the best chance for severe weather will
likely hold off until the low level jet strengthens Thursday
night.

After Thursday, multiple rounds of showers and thunderstorms seem
likely as we stay sandwiched in an active pattern between
ridging to the east and troughing to the west, which by early
next week breaks down into zonal flow. There are PoPs of varying
values basically every day from Saturday through the end of the
forecast period on Wednesday. This by no means is a washout
type of pattern, but rather many small chances for pop up
afternoon/evening thunderstorms or showers, depending on the
day. Rain and storm chances for each day will be refined as
predictability increases.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1224 PM CDT Wed Sep 10 2025

VFR will prevail for the rest of today into early tonight.
After midnight, there is uncertainty regarding two features.
The first is if fog/low stratus develops around KBJI near
sunrise. If this does, we could see IFR for a few hours in the
morning. At this time, added an MVFR period during the timeframe
these lower visibilities/ceilings look the most likely if they
do occur. The other feature of interest is out west at KDVL.
Here, a lower deck of clouds looks to pass through late tonight
into Thursday morning, with embedded showers, maybe even a
rumble of thunder. How low ceilings go, how widespread any
precipitation is, and if there is any thunder associated with
this activity all remains questionable. For now, just added
VCSH and MVFR ceilings for a period of Thursday morning at KDVL.
This will be refined over the next sets of TAFs as
predictability increases.

&&

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

&&

$$

DISCUSSION...Rafferty
AVIATION...Rafferty