744
FXUS63 KGRR 051037
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
637 AM EDT Mon Oct 5 2026
.KEY MESSAGES...
- Areas of Frost Possible Tonight into Tuesday Morning
- Mostly Dry Conditions Into Weekend
&&
.DISCUSSION...
Issued at 205 AM EDT Mon Oct 5 2026
- Areas of Frost Possible Tonight into Tuesday Morning
Some patchy frost is possible this morning as temperatures may dip
around 37 along and north of US-10. Otherwise better chances exist
tonight for more scattered to widespread frost. Depending on the
ensemble, probabilities vary. The highest chances (30 to 50
percent) for frost are in inland areas north of M-20. Dew points
in this area get into the low 30s. With the inversion in place
tonight along with 925 mb temperatures around 6 C and light winds,
low temperatures could drop into the mid 30s. Lower chances exist
further south and along the lakeshore. With some uncertainty in
place, held off on issuing any frost headlines at this time.
- Mostly Dry Conditions Into Weekend
With limited moisture this week, dry conditions are expected to
persist into the weekend. However with a couple shortwave troughs
within the northwest flow aloft, we`ll need to monitor for some
slight rain chances. The first period is Tuesday morning as a
decaying area of showers moves in from Wisconsin. Dry air should
erode these showers before they make it to the lakeshore. The next
is Tuesday night into Wednesday when warm air advection and the
low level jet move in ahead of the front. Overall the better
moisture and lift will be north of the area, but there is a signal
for increased mid level moisture with the current model runs.
We`ll see if this trend continues, if it does PoPs would need to
be added to the forecast.
High temperatures this week will be in the 60s to low 70s with
overnight temperatures in the 30s and 40s. Tuesday night will be
the warmest with lows in the 50s.
&&
.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 637 AM EDT Mon Oct 5 2026
VFR conditions are expected today, FEW diurnal clouds around 4000
feet may develop this afternoon otherwise skies will be clear.
Winds will be from the northwest before becoming light and
variable tonight.
&&
.MARINE...
Issued at 205 AM EDT Mon Oct 5 2026
Northwest winds have picked up along the lakeshore around 20 to 25
knots. High pressure will build in this morning into the afternoon
with lighter winds and wave heights falling below 2 feet
throughout the day.
Southerly winds build Tuesday with Small Craft Advisory conditions
likely. A period of gales is possible toward Little and Big Sable
late Tuesday afternoon into Tuesday evening. A front moves through
Wednesday with winds shifting to the west. Waves 4 feet or greater
will be possible Tuesday into Wednesday morning.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Small Craft Advisory until 8 AM EDT this morning for LMZ844>849.
&&
$$
DISCUSSION...RAH
AVIATION...RAH
MARINE...RAH
NWS GRR Office Area Forecast Discussion
