501
FXUS63 KFGF 280835
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
335 AM CDT Mon Sep 28 2026

.KEY MESSAGES...

- Widespread soaking rains are expected today into Tuesday
  morning. An axis of heavy rain with 90 percent chance of 1
  inch or more and 60 percent chance of 2 inches or more
  forecast roughly Bismarck-Grand Forks/Mayville thru Thief
  River Falls to Roseau/Baudette. WPC has this zone in region of
  sligh risk of excessive rain.

&&

.UPDATE...
Issued at 328 AM CDT Mon Sep 28 2026

Not much change from the current and previous forecast.
Northeast winds under 10 kts currently with advancing area of
mid clouds and mid level showers into NE ND at 08z. Forecast
idea is that winds at the surface will turn more southeast and
dew pts in the 60s which were pushed south to Watertown will
return northward toward Grand Forks this afternoon.
Frontogenetic forcing is focused in a pretty wide area from
south central into east central ND and northwest MN. There has
been a slight southward trend in precip max area but overall
still focused Bismarck to Grand Forks/Mayville region to
Roseau/Baudette where there is a 60 percent chance of 2 inches
or more of rain with a pocket of 25-30 percent chance of 3
inches or more of rain in between Grand Forks and Jamestown.




&&

.DISCUSSION...
Issued at 340 PM CDT Sun Sep 27 2026

...Synopsis...

Mid level clouds continue to work slowly to the east this afternoon,
with otherwise mostly clear skies. Look for increasing cloud cover
tonight as our next system approaches the region. H5 upper low will
move into the Northern Plains on Monday, into an environment
supportive of moderate to heavy rain. Mixing ratios range from 10-12
g/Kg by Monday afternoon, with a relatively strong theta-e gradient
boundary stretching from southwest to northeast across the
eastern half of North Dakota. Embedded thunderstorm activity is
expected as CAPE values will be in the 300-700 J/Kg range. Areas
along an axis from Cooperstown to Grand Forks, to Roseau have
the best chances for 1 or more inches of rain (80-90%), with
slightly lower chances on either side. High temperatures on
Monday will be in the upper 50s along the International Border,
with low 70s in the southern Red River Valley. Heading into
Tuesday, rain gradually moves off to the east, with minimal
chances for precipitation through the remainder of next week.
Cooler temperatures are expected from Thursday onward, with
highs in the 50s to low 60s and lows in the upper 30s to mid
40s.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1130 PM CDT Sun Sep 27 2026

VFR conditions are expected to prevail across eastern ND and
northwest MN through th overnight period. Aviation impacts (MVFR
becoming IFR) are expected after 12Z west to east as a result
of a slow moving but strong system that will bring widespread
rain and at least a chance for thunderstorms Monday into
Tuesday. Best chances for moderate to heavy rain (and associated
vis reductions) along with IFR ceilings will be KDVL- KGFK-KTVF
corridor based on where guidances shows the strongest consensus
on placement of most organized banding of rain. I held off on
introducing thunder mention as the coverage of embedded
thunderstorms may be isolated to widely scattered with rain/rain
showers predominant. East-southeast winds 8-14kt develop Monday
as low pressure builds east.

&&

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

&&

$$

UPDATE...Riddle
DISCUSSION...Lynch
AVIATION...DJR