363
FXUS63 KFGF 072330
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
630 PM CDT Mon Sep 7 2026

.KEY MESSAGES...

- There is a level 1 out of 5 risk for severe storms today. The
  main impacts for any storms that become severe will be golf
  ball sized hail and winds to 60 mph, with a lower risk for a
  tornado in the Devils Lake Basin.

- Heavy rainfall with any slower moving thunderstorms may lead
  to localized flooding in poor drainage areas this afternoon
  into the overnight.

- Windy conditions develop Tuesday with wind gusts to 50 mph
  across parts of northeast North Dakota and the northern Red
  River Valley in Minnesota.

&&

.DISCUSSION...
Issued at 328 PM CDT Mon Sep 7 2026

...Synopsis...

SW Flow is in place across the Northern Plains head of a
stronger mid/upper trough/upper level low located over the
Northern Rockies. This upper low tracks east and deepens over
the Canadian Prairies and passes north of our region through
Tuesday. There is more variation in details beyond Tuesday
regarding any shortwave trough passages and rain
coverage/chances, though we still remain on the warmer side of
temperatures despite a shift towards west-northwest flow on the
back side of this trough. The general trend is for a much more
substantial shift in flow aloft favoring decreasing heights and
temperatures by the end of next week and next weekend (highs in
the 60s). The most likely periods of impactful weather will be
associated with the trough passage tonight and Tuesday
(thunderstorms then wind).

...Severe Thunderstorm and Heavy Rain Risk...

Ongoing showers and embedded thunderstorms have remain weaker in
a much more elevated airmass featuring skinny CAPE profiles
but strong effective shear. Current activity developed with the
nose of a LLJ and elevated WAA in the 850-700 MB layer and
besides heavy rain/lighting it may only feature a marginal hail
threat. Expansive cloud cover is also lingering, which may lower
our window for surface based thunderstorms during the afternoon
and evening.

Surface pattern indicates surface troughing over western ND, with
several fronts intersecting near Dickinson. The deepening of this
surface low and position/timing of these fronts before sunset
will be critical for any potential supercell development to
our west that may track into the Devils Lake Basin/eastern ND
during the evening hours. Forcing is much more diffuse before
the main trough starts shifting east later this
evening/overnight, so coverage/initiation carries more
uncertain. Still, within the warm sector where clearing develops
decent instability profiles may coincide with strongly veered
hodographs/strong shear favorable of supercells and a
conditional risk for hail around the size of golf balls and a
conditions risk for tornado development. Some CAMs (mainly runs
of the HRRR) have supported supercell developing to our west and
potentially tracking east into our west. The farther east and
the later activity lingers/tracks activity will tend to become
weaker with more of a marginal hail risk.

Higher PWATs in place raises potential for heavy rain rates with
thunderstorm activity once again as with previous days, and any
slower moving/training clusters could lead to localized
flooding.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 630 PM CDT Mon Sep 7 2026

Variable flight conditions are forecasted throughout the TAF
period. To start, south/southeasterly winds will die down after
sunset this evening, losing their gusts. A few thunderstorms may
push in from the west at KDVL after sunset, therefore maintained
a PROB30 at that terminal. Probabilities for thunderstorm
activity was too low at all other terminals to include in the
TAF. Overnight, a period of MVFR stratus looks to develop at
KBJI, sneaking into KTVF as well. Ceilings may flirt with IFR
at times, especially around sunrise. There is also some model
guidance that brings MVFR back as far west as KGFK and KFAR.
While a low probability scenario, it is worth mentioning
considering how stubborn cloud cover has been the past several
days.

A front passing through overnight into Tuesday morning will
bring a shift in wind direction, along with a rapid increase in
wind gusts. Gusts in excess of 30 knots are forecasted at KDVL,
KGFK and KFAR for at least several hours on Tuesday. The
strongest winds will occur during afternoon hours, especially at
KGFK and KDVL.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...Wind Advisory from 10 AM to 7 PM CDT Tuesday for NDZ006>008-
     014>016-024-026>030-054.
MN...Wind Advisory from 10 AM to 7 PM CDT Tuesday for MNZ001-004-
     007.

&&

$$

DISCUSSION...DJR
AVIATION...Rafferty