Area Forecast Discussion
Issued by NWS Grand Forks, ND

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43
800
FXUS63 KFGF 282333
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
633 PM CDT Fri Aug 28 2026

.KEY MESSAGES...

- Minor chance for isolated flash flooding tonight across
  southeast North Dakota and west central Minnesota.

- There is a level 1 out of 5 risk for isolated to scattered
  severe storms tonight through Sunday.

&&

.DISCUSSION...
Issued at 355 PM CDT Fri Aug 28 2026

...Synopsis...

Relatively low amplitude longwave ridging will allow a series
of shortwaves to permeate east along the top of the ridge
through early next week bringing above average moisture to the
region for the 6-10 day period. With these shortwaves will come
a minor risk of flash flooding and low end severe chances
(mainly wind/hail) each day through Sunday. Beyond these threats
the rains will certainly be welcome and beneficial to easing
the worsening drought though is likely too little, too late for
many crops unfortunately and may even put a short stop to the
ongoing wheat/sugar beet harvest. Dry/hot Ridging does briefly
return for the middle of next week before we transition to
prevailing SW flow aloft indicating another wet period though
uncertainty remains on any amounts or associated hazards
(flooding/severe).

- Today

Machine learning remains pessimistic overall about the chances
for any severe weather tonight with hail being the only thing
really sticking out. Overall buoyancy is pushing 2000-2500
MUCAPE with 40kts of eff shear. Overall the marginal risk for a
couple quarter sized stones is warranted but the threat seems to
be more of a heavy rain one. The saturated profiles aloft could
be an artifact of convective contamination on the CAMS but
assuming they are not that type of profile does not fit the
conceptual model for efficient hail growth. Conversely the
elevated nature of parcels given inflow layers around 800-850mb
and long straight hodos should favor hail growth. Its really a
tossup between if hail occurs or it goes the way of efficient
warm cloud layers producing a predominant heavy rain threat.
Should hail occur analogs support hail of golf ball to baseball
but would think the max size would trend toward the lower bound
of that range.

That said the pattern does overall resemble the Maddox Frontal
Pattern with the ridge to the western and a shortwave
paralleling the stalled 850-700mb front. Sustained overnight
southerly moisture return along with general WAA across the
front combined with cloud layer (850-300mb) shear of ~40kts atop
deep moisture convergence should favor repeated training storms
in southeast North Dakota and west central Minnesota overnight.
Some CAMS are outputting areas of 2-4" with many areas likely
to see at least quarter inch tonight easy the drought south of
HWY 200. The confidence in these higher totals manifesting is
currently too low to issue a Flood Watch but it remains
something to be monitored tonight (10pm to 8am).

- Saturday

Another shortwave is forecast to crest the flattening ridge on
Saturday with a developing surface low on the MT/ND border. This
will bring more strong southerly moisture return to north
central North Dakota and a marginal risk for severe weather to
the western 2/3rds of the state. A few strong storms may make
into the Sheyenne river valley but most stay west of the Red
River Valley. HREF PMM is showing areas of 1-2" with this
activity but it mostly remains west of our forecast area
unfortunately. Could still see a few areas in north central
North Dakota with amounts exceeding a quarter to half inch but
those will be the lucky few rather than the norm for our
forecast area.

- Sunday

More storms are yet again expected Sunday afternoon/evening as
yet another shortwave moves east through Montana initiating
storms along the state border around 5-7pm working east as an
line as eff shear of 40-50kts and MUCAPE of 2500-3000 looks to
favor linear modes with time. Right now the ceiling looks to be
a strong MCS perhaps with hail initially west of Bismarck and
winds up to 70mph out here. Should the low levels be favorable
some mesovortex type tornados cant be ruled but will have to
monitor that threat more over the next 24 hours as CAMS become
available.

- Next Week

Near zonal to southwesterly flow aloft continues into next
week. Temps look to be above average with several chances for
precipitation as weak shortwaves come through. Timing and
intensity of any storms still uncertain with such weak forcing
and unknown instability.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 633 PM CDT Fri Aug 28 2026

VFR conditions with a few showers between KGFK and KFAR.
Additional shower and thunderstorm chances there and at the MN
airports, although highest certainty is further south. Kept KFAR
prevailing and just went Prob30 for the others. KDVL should see
most of the shower and thunderstorm activity east of their
area, so kept it just high cloud cover. Winds that are
southeasterly around 10 to 15 kts will drop in speed below 10
kts tonight, becoming more easterly at several of the TAF
sites tomorrow.


&&

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

&&

$$

DISCUSSION...TT
AVIATION...JR