792 FXUS63 KGRR 220106 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 906 PM EDT Wed Oct 21 2026 .KEY MESSAGES... - Dry with Morning Fog - Chances for Rain Return Next Week && .UPDATE... Issued at 905 PM EDT Wed Oct 21 2026 No significant changes to the near-term forecast. MKG has already started to see some reductions in visibility this evening, becoming more widespread overnight thanks to favorable radiational cooling conditions. 18z REFS probs continue to show a similar story as noted earlier with 40-70% chance of sub 1 mile visibiliites overnight. The best model signal for fog is north of I-96 and west of US131, but given the favorable synoptic setup, the threat for locally dense fog exists areawide. Reduced visibilities and associated traffic slowdowns remain possible for the Thursday morning commute. && .DISCUSSION... Issued at 205 PM EDT Wed Oct 21 2026 - Dry with Morning Fog Our period of dry weather will continue through the weekend. A shortwave trough and associated front will swing through this evening. This is currently located in the UP into northern Wisconsin. There is limited moisture with this disturbance, therefore only expecting some cloud cover to move in. Skies clear overnight with a moderate inversion developing and temperatures falling into the upper 30s to low 40s. HREF and REFS show a 40 to 60 percent chance of visibilities less than a mile across much of the area. The best chances are north of I-94. Fog could bring slow downs for the Thursday morning commute. Through the rest of the week we`ll see mostly sunny skies with highs in the 60s and lows in the upper 30s to mid 40s. There is the potential for fog each morning as well. - Chances for Rain Return Next Week The upper level pattern changes for next week bringing several shortwave troughs through the region along with better moisture. This can be seen in the long range ensemble members that start to bring in precipitation chances as early as Monday. More members are dry Monday, therefore the NBM does not highlight any chances. A larger number of members show rain Tuesday into Wednesday with chances likely lingering through the rest of the week. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 714 PM EDT Wed Oct 21 2026 An upper trough is moving across the Lower Peninsula. This trough produced a band of showers over Wisconsin but that has largely dissipated over MI. We`ll see mostly clear skies through the period. Outside of MKG where IFR/LIFR visibilities are possible late tonight, some patchy fog is expected at the other terminals, Any fog that develops will burn off by mid morning. && .MARINE... Issued at 205 PM EDT Wed Oct 21 2026 Dry conditions continue with high pressure remaining in the area keeping wave heights around a foot or less through Friday. Southerly winds build this weekend and may approach Small Craft Advisory criteria Saturday north of Grand Haven. Waves will also build Saturday as well with the potential for 4 foot waves around 5 NM from shore north of Whitehall. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...None. && $$ UPDATE...Thomas DISCUSSION...RAH AVIATION...04 MARINE...RAH

NWS GRR Office Area Forecast Discussion