780
FXUS63 KGRR 041705
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
105 PM EDT Sat Oct 4 2025

.KEY MESSAGES...

- Late summer-like weather through Monday then showers and
  temperatures falling

&&

.DISCUSSION...
Issued at 200 AM EDT Sat Oct 4 2025

- Late summer-like weather through Monday then showers and
  temperatures falling

Upper ridging and southwest flow persists into Monday with 850 mb
temps around 15-16C and highs in the 80s. Low level moisture
return increases ahead of an advancing western CONUS trough and a
cold front is expected to focus showers and a few thunderstorms
Monday evening into Tuesday.

The front clears Lower Michigan Tuesday night with dry northerly
flow as high pressure builds in. There could be some frost by
Wednesday morning with a better chance for frost and freezing
conditions Thursday morning.

The sfc high moves east with return moisture and an upper low
bringing the chance of showers by the end of the week.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 102 PM EDT Sat Oct 4 2025

High confidence in VFR conditions through the TAF period as dry
air is in place. Southwest winds to 10 knots today become
southerly and subside to near 5 knots overnight. Increasing
gradient winds will lead to southwest winds around 10-15 knots
again Sunday. At MKG interaction with the lake will support gusts
to around 20 knots in the late morning into the afternoon.

&&

.MARINE...
Issued at 200 AM EDT Sat Oct 4 2025

Surface pressure gradient will tighten over the next couple days
with increasing south to southwest winds. Conditions are expected
to become hazardous to small craft on Sunday north of Holland and
possibly south of there on Monday. A cold front moves through by
Tuesday with north winds possibly gusting over 25 knots at times
Tuesday afternoon and evening.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.

&&

$$

DISCUSSION...Ostuno
AVIATION...Thomas
MARINE...Ostuno