979
FXUS63 KGRR 010704
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
304 AM EDT Thu Oct 1 2026

.KEY MESSAGES...

- Rain ending Friday

- Cooler with frost/freeze possible into next week

&&

.DISCUSSION...
Issued at 304 AM EDT Thu Oct 1 2026

- Rain ending Friday

National radar shows a large band of rainfall from Michigan
southwest to the southern Plains, moving northeast. The rain is
ahead of a cold front that will move across the cwa Friday. Deep
south flow is in place east of the front and is drawing moisture
northward from the Gulf as well as from the eastern Pacific, where
the remnants of the tropical system have been entrained into the
upper flow. This added moisture has resulted in flooding in the
Mid MS Valley. However, flooding isn`t expected within the cwa.
Light to occasionally moderate rainfall will continue into the
overnight. Additional rainfall accumulations of a half to around
an inch are possible. Once low pressure over Kansas moves
northeast along the frontal boundary into Michigan, the cold front
will move southeast across Lower MI beginning tonight and
continuing into Friday. As high pressure builds in behind it,
we`ll see decreasing cloudiness throughout the day. Dry weather
will then continue through the weekend and much of next week.

- Cooler with frost/freeze possible into next week

Clear skies and light winds will set up radiational cooling
conditions. Temperatures in the upper 20s are possible along US-10
with lower to mid 30s as far south as M-20. Thus, frost/freeze
headlines are likely tomorrow night. After another cold frontal
passage Sunday, additional frost/freeze headlines are possible
Sunday night and Monday night. Monday night will be the coldest of
the season so far. Lows Monday night will be in the mid to upper
20s north of M-20 and in the lower to mid 30s south through the
rest of the cwa. Highs during this period will be in the lower to
mid 60s.


&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 145 AM EDT Thu Oct 1 2026

I-96 is the rough delineation between VFR conditions to the south
and IFR to the north. This is where the front aloft is located.
This boundary may wiggle back and forth a bit through early
afternoon before sinking south and dragging IFR cigs with it.
Thus, we have IFR conditions at all of the terminals at some
point this afternoon, continuing through the remainder of the
period.

&&

.MARINE...
Issued at 304 AM EDT Thu Oct 1 2026

The marine headlines have been canceled due to wind and waves
falling below advisory/statement criteria. We`ll have a 24 hour
period of low wind/waves before north winds develop behind a cold
front early Friday morning. At that time, we`ll likely need
another small craft advisory as north winds will push waves to 4
to 6 feet.


&&

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

&&

$$

DISCUSSION...04
AVIATION...04
MARINE...04