771
FXUS63 KGRR 251803
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
203 PM EDT Sun Oct 25 2026
.KEY MESSAGES...
- Cooler To Start The Week
- Warming Into Midweek With Showers Possible
- Widespread Rain Returns This Weekend
&&
.DISCUSSION...
Issued at 202 PM EDT Sun Oct 25 2026
- Cooler To Start The Week
Mid-level water vapor imagery continues to show ridging across the
central Great Lakes region today which is keeping fair conditions
across the region. Surface observations upstream show a cold front
forecast to drift across the region overnight. Frontal passage is
favored to be dry, with just clouds across southwest Michigan. Can`t
rule out light showers across Central Lower Michigan though
probabilistic guidance keeps chances less than 15 percent. These
clouds will lower the fog threat across the area, which is well
reflected in NBM and REFS probabilistic guidance. Post frontal highs
Monday and Tuesday will be in the low to mid sixties for most.
- Warming Into Midweek With Showers Possible
Southerly flow behind a warm front arrives late Tuesday bringing
warmer conditons mid-week. Highs are favored to rebound to near
seventy which is notably above average (which is the upper fifties
this time of year). Decent signal exists in guidance for showers and
maybe isolated thunderstorms given weak elevated instability between
late Wednesday and late Thursday.
- Widespread Rain Returns This Weekend
A shortwave associated with the arrival of the more active
subtropical jet marks the beginning of more widespread rain chances
this weekend. Some question of whether rain impacts Halloween (PoPs
around 40 percent as of present) or holds off until late
Saturday/early Sunday. Rain continues into Sunday as well. Ensemble
guidance has a mean of around 0.5 inches, with 90th percentile (high
end) amounts of 1.5-2 inches possible in spots. So overall soaking
rain is expected this upcoming weekend into early next week.
&&
.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 123 PM EDT Sun Oct 25 2026
A weak cold front will sag south across the region tonight,
effectively switching surface winds from the west to the
northeast. We may continue to see some MVFR fog after 09z but IFR
will be mitigated by high clouds overhead limiting radiational
cooling.
&&
.MARINE...
Issued at 202 PM EDT Sun Oct 25 2026
Short range model guidance continues to show a burst of winds to
around 20 knots behind a cold front overnight into Monday near Big
and Little Sable points. The north-northeast flow looks to keep
waves below criteria, and winds look to be just below as well based
on the latest BUFKIT overviews. So will hold off at this time on an
advisory, but a slightly more onshore direction would potentially
bring 3-5 ft waves around the points. Next chance for hazardous
winds and waves then arrives Wednesday as southwest winds increase
ahead of a cold front.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.
&&
$$
DISCUSSION...Thomas
AVIATION...04
MARINE...Thomas
NWS GRR Office Area Forecast Discussion
