427
FXUS63 KFGF 061555
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
955 AM CST Sat Dec 6 2025

.KEY MESSAGES...

- Below average temperatures this weekend.

- Early to mid next week...active period with stronger system
arriving Tuesday, with a 70 percent chance of at least  advisory
level impacts.

&&

.UPDATE...
Issued at 954 AM CST Sat Dec 6 2025

Light snow and flurries continue to extend from Cooperstown to
Fargo, but at this point impacts still seem very minimal.
Visibility at Gwinner has gone down to 1 mile in BR but web cams
and ND DOT reports are still showing snow, although very fine
flakes. Made some minor tweaks for timing, but overall no
changes to the overall messaging of a trace to a few tenths of
an inch in southeastern ND.

UPDATE
Issued at 632 AM CST Sat Dec 6 2025

Area of light snow extending east-southeast toward Fargo. This
overall is a bit farther north than most operational models have
shown. But it is also running into a drier airmass and snow is
starting to develop in central SD which will become the main
snow area heading into the afternoon. Will watch pops but may
need to expand pops a bit more east.

&&

.DISCUSSION...
Issued at 341 AM CST Sat Dec 6 2025

...Synopsis...

Sfc high pressure is building into the northern RRV with its
center in northeast Alberta. Drier air is upstream at 850 mb
pushing southeast, but still having areas of stratocu lower
clouds hanging around far southern Manitoba and into northeast
ND and far northwest MN. But elsewhere the lower clouds have
lifted and more mid clouds moving east-southeast thru the area
in advance of the current short wave in Montana. Light snow in
mid level warm advection zone is in northwestern into central ND
at 08z. It is running into a lot of dry air though as it moves
east. Expectation today is that the light snow in central ND
moves southeast and is rather weak, while a newer area of snow
develops in an area of stronger 850 mb warm advection that forms
in advance of a stronger short wave moving out of Wyoming this
afternoon. Snowfall to expand and intensify in the Sioux Falls
and moves east thru far southern MN and northern Iowa late today
and tonight with lingering very light snow northwest thru
northeast and north central SD into parts of southern ND. The
northern light snow eventually dries out as sfc high drops
southeast toward Saskatoon by 21z today and then into central
and eastern North Dakota tonight. Should see clearing of most of
the clouds as this occurs into tonight, but high clouds will
quickly advance east heading into Sunday morning.

Only area to see very light snow today will be far southeast ND
with amounts trace to a few tenths. Until the stratocu
dissipates a few flurries possible from any cloud that moves
over so did keep some mention of flurries in many areas thru
midday.

Sunday afternoon and night will see an area of 850-700 mb warm
advection push east behind departing high. Some light snow with
this warm advection Sunday night, but another trace to a few
tenths at most.

Early next week... one system for which models disagree on
strength is on Monday as a clipper wave moves southeast from
central Saskatchewan into the Red River by 00z Tue. Narrow band
of frontogenetical may develop with this wave in a narrow zone
just north of the sfc low and there is good consensus among
models and ensembles of a narrow zone of 1-2 inch snowfall
potential near the Minnesota/North Dakota/Manitoba border area
Monday night.

...Tuesday system...

In our never clipper train, we do have a stronger system that
has more moisture with it and comes onshore from the Pacific
into west central British Columbia Monday and quickly develops
surface low in west central Alberta and tracks southeast along a
likely baroclinic zone separating temps above freezing from
temps in the 20s and teens. 850 mb low, 700 mb low and sfc low
development Monday afternoon into Monday night will occur
quickly as it moves into southern Saskatchewan, with a
strengthening 850 mb jet of 50 kts east of the 850/sfc low
creating a strong warm advection zone and sufficient lift for a
band of moderate to potentially heavy snowfall. This would be
just north of the sfc/850 mb low and its track. All models and
ensembles from Canadian global, ECMWF, GFS, ICON, AI models are
in good agreement that this system will impact a large part of
our forecast area with WPC indicating at least a 70 pct chance
of advisory level impacts thru a large part of the area...focus
of these impacts though are still not as clear cut as would
hope. But that is to be expected this far out. Operational 00z
GFS is a tad farther north and NBM is a bit farther north than
00z ECMWF operational and ensemble suite with GFS highest probs
of more than 3 inches snow DVL-GFK-BJI while ECMWF a bit more
northwest-southeast focus from Minot to Fargo. 00z ECMWF 12/4
Extreme Fcst Index (EFI) shows a strong signal for impacts with
snow in that area from southeast Sask thru north central into
east central and southeast MN into parts of west central MN.
Wind to be a factor, though if low takes the path above, then
highest winds will be in the cold advection west and southwest
of the low in SW ND into central SD. But does look like a period
of north winds using ECMWF and GFS ensembles of 30 kts Tues
night...esp 06z-12z Wed period. So it is possible that snowfall
amounts may be in advisory impacts, but if we do get stronger
winds then it may be enough to push overall impacts into warning
range. (10 percent chance).

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 632 AM CST Sat Dec 6 2025

Starting off this morning with a mix bag of MVFR and VFR. Areas
of MVFR cigs continue to develop in southern Manitoba and streak
southeast thru NE ND and NW MN. Other areas cloud bases lower
end VFR with mix of MVFR. So for most of today a mix of MVFR and
low end VFR cloud bases. Light NNE wind turning north 4-8 kts.
Should see better clearing tonight and MVFR stratocu should
clear out as airmass dries out at the 850 mb layer.

&&

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

&&

$$

UPDATE...Riddle/JR
DISCUSSION...Riddle
AVIATION...Riddle