228
FXUS63 KFGF 101729
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
1229 PM CDT Thu Sep 10 2026

.KEY MESSAGES...

- Near critical fire weather conditions this afternoon parts of
  southeast North Dakota.

- There is a level 2 out of 5 risk for severe storms Friday
  afternoon and evening for portions of west central into north
  central Minnesota and far southeast North Dakota. All hazards
  are possible.

- There is a high chance for soaking rainfall Sunday night into
  Monday night across the region which could impact outdoor
  activities.

&&

.UPDATE...
Issued at 414 AM CDT Thu Sep 10 2026

Skies are clear to partly cloudy as sunrise approaches this
Thursday. Surface winds are already south to southwest around 5
kts and will increase in to the 10-20 kt range today, with a few
gusts 25 kts in E ND. The last HRB (Herbaceous Fuel Moisture)
map shows sub 100 values in southeast ND in the dry region. With
RH values anticipated to drop to near 30 percent in parts of SE
ND and with wind gusts 25 mph did add near critical fire weather
conditions to the HWO for southeast ND. For Friday mid afternoon
and evening SPC day 2 pushed slight risk a tad west and
introduced a 5 pct TOR in parts of the MN forecast area from
Alexandria to Bemidji to Grand Rapids.

&&

.DISCUSSION...
Issued at 309 PM CDT Wed Sep 9 2026

...Synopsis...

Northwest flow is in place across our region on the back side
of the upper low now centered over Hudson Bay. Shortwave ridging
moves over the region Thursday followed by southwest flow ahead
of deepening troughing over the Northern Rockies and Pacific
Northwest. After a near seasonable day today, much warmer
temperatures return Thursday and Friday over much of the region,
though there may be a larger spread in temperatures Friday due
to the arrival and timing of a strong cold front. This front
Friday brings the next chance for organized thunderstorms to
parts of the region (mainly MN). Much more seasonal or even
below average temperatures return this weekend into next week
behind that front and lowering heights in response to several
deepening upper lows in Canada and the Pacific NW that will
migrate over our region.

...Severe Risk Friday Afternoon and Evening...

Southerly flow ahead of the cold front Friday brings increased
BL moisture (Tds 62-68F) and a narrow corridor of higher
instability (MLCAPE 2000-3500 J/KG) in response to steepening
mid level lapse rates (7.5-8.5 C/km). Increased mid level flow
will bring effective shear values in excess of 40kt to much of
our region, and ahead of the cold front there is a window where
hodographs are supportive of supercells and even some supportive
of dominant right moving supercells and tornadoes. The tornadic
environment may remained more capped before forcing increases
and shear profiles change in in our area making the threat more
conditional. Ultimately, the location, coverage, and impacts of
severe thunderstorm activity will be determined by the cap
weakening and the frontal timing during the afternoon/evening.
Ensemble/deterministic guidance have zeroed in at this range on
a timing favoring mainly our western MN/north central MN
counties. This is also reflected in AI based systems which show
strong signals for severe impacts in those regions. The ceiling
on impacts for this event includes s significant severe impacts
from hail (2"+), a conditional risk for tornadoes, and damaging
wind gusts to 70 mph. though there are enough uncertainties that
there are equal or greater chances impacts end up lower due to
how narrow the window/corridor for the higher end of parameters
will be. This is certainly a set-up to monitor.

...Soaking Rainfall Sunday night into Monday night...

There is strong consensus that a strong upper low will bring
widespread rainfall to our region Sunday night through Monday.
NBM probabilities are 60-80% for greater than 0.5" rainfall in
our CWA during that period, and probabilities for greater than
1" of rain range from 40-60% (highest in the southern RRV).
While it is an organized synoptic system, the locations that
receive 1"+ or even 2"+ rainfall (30% chance) will be determined
by deformation zone location and embedded thunderstorm activity
which will be less predictable. As the warmer more unstable air
mass will be cut off to the south of this system there is
currently not a signal for severe thunderstorm risk after
Friday.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1229 PM CDT Thu Sep 10 2026

VFR conditions are forecasted throughout the TAF period.
Southerly winds this afternoon will occasionally gust up to
about 20 knots at terminals in the Red River Valley and west.
Winds will decrease after sunset, with gusts dropping off. Winds
will shift to the north/northwest Friday morning at KDVL, and
late morning at KGFK. This wind shift is associated with a cold
front that will keep pushing southeastward Friday afternoon
beyond this TAF period, eventually switching winds at all
terminals.

&&

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

&&

$$

UPDATE...Riddle
DISCUSSION...DJR
AVIATION...Rafferty