222
FXUS63 KFGF 041730
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
1230 PM CDT Thu Jun 4 2026

.KEY MESSAGES...

- Widely scattered showers and weak thunderstorms are forecast
today. Storms are not expected to be severe.

- More widespread chances for showers and storms this weekend  into
next week. Some storms could be strong to severe.

- Heat returns for the weekend.

&&

.DISCUSSION...
Issued at 239 PM CDT Wed Jun 3 2026

...Synopsis...

The main upper low continues to slowly rotate over southern
Saskatchewan, eventually pulling into southern Manitoba tonight.
The slow forward progression of the upper system will help move
the surface trough axis currently over the Dakotas off into MN
overnight. The upper low will continue to push off into Ontario
tomorrow, with many ensemble members showing a weak embedded
shortwave near the SD/ND border. Best instability will be well
to our south thanks to the surface trough axis moving into
eastern MN into SD. Could see some edges of convection straying
into our far south tomorrow, but think most of the severe risk
will be in SD and MN. Similar story on Friday with a weak
shortwave trailing behind the main upper low, but most of the
best instability will be to our south. Upper ridging builds back
into the Plains on Saturday and moves a bit east into the Great
Lakes on Sunday. Sunday night into the first part of next week,
southwesterly flow aloft returns to the Northern Plains, with
various weak shortwaves and some instability returning. A warm
and active pattern is likely, although mesoscale details are
impossible to resolve at this point.

...Severe potential this afternoon and tonight...

A weak shortwave/vort max continues to move into south central
ND, with showers/weak thunderstorms progressing towards
southeastern ND. Most of the activity is behind the surface
trough axis, but could see something pop in the warmer air
ahead of the feature. With the forcing moving into 1000-1500
J/kg of ML CAPE and some 30 kts of shear, expect some
intensification as the system pushes east. Instability is not
quite as high as yesterday with clouds and recent rainfall, but
there is some clearing along the Red River Valley and daytime
heating will continue. Machine learning models have backed off a
bit on the tornado threat for this afternoon and evening,
although CAMs like the HRRR still try and develop some random
supercells before 00Z. By the time the trough axis/cold front
pushes into our area, there is some indication of storms
becoming linear, although a few models keep cells fairly
discrete. Still getting some 70 percent probabilities of strong
updraft helicity tracks nosing into our far southwestern
counties, and severe is possible even as models have been
trending down a bit with the tornado threat.

...Heat into the weekend...

With upper ridge building back north and southerly winds
returning ahead of the surface trough over the High Plains,
temps will warm back up over the weekend. The ECMWF EFI has 70
to 80 percentile signal for above average temperatures, and by
Sunday the NBM probabilities of over 90 degrees in the Red River
Valley are over 60 percent. Dew points currently in the upper
50s to low 60s, so heat index doesn`t look too bad yet but will
continue to monitor as some of the other heat risk indicies are
creeping upward.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1230 PM CDT Thu Jun 4 2026

VFR conditions at all TAF sites although some lower ceilings
have been hanging around KBJI and scattered in and out. Will
keep them at 3500 ft for now. Other sites should see increasing
mid and high clouds later in the period. West to southwest
winds mostly under 12 kts will shift around the northwest at
some of the more northern sites this evening. Then become light
and variable everywhere.

&&

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

&&

$$

DISCUSSION...JR
AVIATION...CJ