304 FXUS63 KGRR 050605 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 205 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 /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 205 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 mostly 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