288
FXUS63 KGRR 080810
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
310 AM EST Sun Feb 8 2026
.KEY MESSAGES...
- Snow passes mainly southwest of forecast area this morning
- Snow passes mainly north of area Monday night
- Increasing precipitation chances by this weekend
&&
.DISCUSSION...
Issued at 310 AM EST Sun Feb 8 2026
- Snow passes mainly southwest of forecast area this morning
The SPC mesoanalysis 800-750mb EPVg display nicely tells the story
regarding the northwest-southeast oriented FGEN snow band passing
east of Chicago at this time. There is a sharp reflectivity gradient
on the west side of this band, indicating good coupling between the
ascending branch of the FGEN response and the overlying layer of
negative EPV (conditional instability). The consequent narrow,
sharply focused snow band will give far southwest Lower MI a
glancing blow of little to no accumulations. For the rest of the
forecast area, accumulating snow is looking far less likely due to
subsidence contributed from both shortwave ridging aloft (per water
vapor imagery) and mesoscale subsidence poleward of the FGEN band.
- Snow passes mainly north of area Monday night
As noted previously, a northern stream shortwave trough and clipper
tracks north of Lower Michigan Monday into Tuesday. Model guidance
indicates low chances for accumulating snow to reach as far south as
our northern forecast area. For example, regarding probabilities of
exceeding a tenth of an inch of accumulation, latest REFS guidance
indicates a 50 percent chance of this happening in Clare County (our
far northeast forecast area), whereas 08/01Z NBM guidance gives just
a 10 percent chance of this happening north of US-10.
Tuesday will be the warmest day in quite a while prior to colder air
filtering in behind the exiting clipper. High temperatures farther
south towards I-94 could make a run at 40 degrees.
- Increasing precipitation chances by this weekend
It seems likely that dry conditions will prevail in the Tuesday to
Thursday timeframe with surface high pressure centered in the area.
Precipitation chances nudge upward beginning late Thursday/Friday
and continue into the weekend. This uptick in precipitation
chances is partly associated with the typical growing uncertainty
that occurs at longer forecast projection times and this will
usually trend the forecast towards climatological PoPs.
The other reason behind this uptick in PoPs is that we do see a
signal for longwave troughing in the west and downstream ridging
somewhere in the mid-section of the CONUS by the weekend. Cluster
analysis shows growing agreement with this solution among the
medium range ensembles. The main questions are amplitude and phase
speed of this wave. Although precipitation details are a bit
tough to iron out at this point, what`s more certain is a warmer
pattern due to upper ridging centered near or perhaps just east of
our longitude, accompanied by deep southwesterly flow. Some
guidance like the AI GEFS even suggests much of the southern
forecast area could get into the 40s by Sunday. This should
provide a clue that precipitation type could be more of a
rain/snow mix, with a non-zero probability of some freezing rain
as well.
&&
.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1121 PM EST Sat Feb 7 2026
A weak upper disturbance will slide southeast through the Great
Lakes region late tonight and Sunday morning. The disturbance will
bring a chance for some light snow to far Southwest Lower
Michigan, potentially grazing the TAF sites of MKG, AZO and GRR.
Have opted to bring some very light snow into AZO (6SM -SN) and
VCSH to the other two sites. Moisture takes a while to saturate in
the low levels at these sites and overall this will result in very
little to no snow at the TAF sites. Ceilings will remain VFR only
dipping to around 5000 feet at AZO. Any snow associated with this
system will pass to the south Sunday morning and ceilings will
then lift through the afternoon, more into a mid deck with bases
at or above 7,000 feet. By Sunday evening we will be scattering
out. Bottom line, VFR weather is expected at all TAF sites over
the course of the next 24 hours, from 06z to 06z. The only place
of concern would be AZO with a small potential of some
visibilities below 6SM for a few hours towards 12z. Winds will be
light from the northeast and east tonight, becoming southeast on
Sunday.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.
&&
$$
DISCUSSION...TJT
AVIATION...Duke
NWS GRR Office Area Forecast Discussion
