Dansville, Michigan Weather Forecast Discussion

068
FXUS63 KGRR 141826
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
226 PM EDT Sun Sep 14 2025
.KEY MESSAGES...
- Areas of Fog Tonight North of I96 and East of US131
- Dry With Summer-Like Conditions This Week
- Rain Chances Return Late Friday Into The Weekend
&&
.DISCUSSION...
Issued at 222 PM EDT Sun Sep 14 2025
- Areas of Fog Tonight North of I96 and East of US131
Clear skies are ongoing across West Michigan this afternoon with the
only concern over the next 24 hours being some fog tonight. Easterly
flow off of Lake Huron/Saginaw Bay will bring in some enhanced low-
level moisture with favorable radiational cooling conditions. This
will lead to areas of fog developing, mainly north of I96 and east
of US131. Any fog should burn away shortly after sunrise.
- Dry With Summer-Like Conditions This Week
The overall large scale pattern for much of the week will be a Rex
block across the eastern CONUS. With us under the upper-level
ridging portion this will bring several days of decent sunshine
and dry conditions. This pattern drives the forecast through
Thursday before breaking down and moving off to the east. 850 mb
temperatures in the mid teens will translate into highs well into
the 80s, with a low (~10 percent) chance of highs reaching 90
Wednesday/Thursday across Southern Michigan.
- Rain Chances Return Late Friday Into The Weekend
Once the Rex block breaks down, the approach of upper-level trofing
will bring rain chances, and possibly a few thunderstorms, back into
the forecast for this weekend. However, uncertainty remains elevated
as to when and how much precipitation falls. Questions as to the
strength/position of upper-level waves and the extent a strong
high over Ontario affecting moisture quality have the outgoing
forecast with several periods of low (15-30 percent) rain chances.
However, the outcome is likely to be periods of spotty showers
with very light accumulation within this timeframe.
&&
.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 142 PM EDT Sun Sep 14 2025
Little to no aviation concerns are expected the next 24 hours.
Skies are expected to be mainly clear outside of some FEW-SCT
cumulus development out of the east this afternoon and early
evening. Overnight we are expecting some fog and stratus to form
with a push of moisture off of Lake Huron in easterly flow. The
bulk if not all of the fog should be north of the TAF sites across
Central Lower Michigan. We did bring 4 miles and fog into the LAN
TAF in the 10z to 14z time frame as that airport will be closest
to the fog bank. The fog will burn off rather quickly Monday
morning. Bottom line, mainly VFR weather expected across the TAF
sites through 18z Monday. Winds will be light easterly the next 24
hours.
&&
.MARINE...
Issued at 222 PM EDT Sun Sep 14 2025
Light winds and little wave action will be the dominant mode for
much of the upcoming week. High pressure will remain over the Great
Lakes for the early portion of the work week with a weak front and
slack gradient mid week. The next stronger wind does not look like
it appears until the end of the week and that wind will be off
shore. So, we are likely looking at waves of less than 2 feet right
through the work week.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.
&&
$$
DISCUSSION...Thomas
AVIATION...Duke
MARINE...Duke

NWS GRR Office Area Forecast Discussion