303 FXUS63 KGRR 261848 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 248 PM EDT Mon Oct 26 2026 .KEY MESSAGES... - Cool and dry again tomorrow - Warmer mid-week, with shower chances Thursday - Rain chances steadily increase this weekend onward && .DISCUSSION... Issued at 131 PM EDT Mon Oct 26 2026 - Cool and dry again tomorrow In spite of the persistence of anomalous ridging aloft, temperatures are a bit more seasonable this afternoon behind this morning`s weak cold front, albeit technically still a few degrees above average overall. We`ve also seen a modest increase in cloud cover across primarily the northern lower peninsula thanks to a plume of mid-level moisture, but this has largely remained to our north, and is not producing any precipitation aside from a few pockets of virga. Overnight, surface winds will slowly veer to the east, which should maintain weak cold air advection and lead to a chilly morning in the mid 30s to low 40s, in spite of some lingering cloud cover. Surface winds will continue to slowly veer to the southeast tomorrow, but cooler low level air will remain in place for one more day of seasonable, fall-like temperatures. Precipitation is also not expected tomorrow as we await another weak cold front late Wednesday and Thursday. - Warmer mid-week, with shower chances Thursday Between Wednesday and Thursday, a synoptic scale ridge aloft will remain firmly in place across the eastern U.S., and a weakening shortwave and associated surface low will move around its periphery across southern Canada. This will bring the return of south to southwesterly winds and modest warm air advection Wednesday, followed by a diminishing cold front Wednesday night and Thursday. The former is expected to drive another warming trend and bring temperatures back to comfortably average values Wednesday afternoon (low 70s). Meanwhile, confidence is increasing that the weakening front will bring a round of light showers to the area Thursday, although precipitation amounts should be quite modest (10-30% chance of more than 1/4 inch). There remain some hints of very weak instability as well, so we can`t rule out a weak rumble of thunder or two, either. Similarly warm temperatures can also be expected Thursday, although perhaps a few degrees cooler thanks to the increasing cloud cover. - Rain chances steadily increase this weekend onward Confidence in the day-to-day details decreases considerably Friday onwards, thanks to the gradual development of a more unsettled pattern and increasingly divergent ensemble members. The aforementioned weak cold front is expected to sink south of the area sometime Thursday, but anomalous ridging aloft will be difficult to dislodge over the weekend, and this front will likewise not be followed by a significant surge of cooler air. However, shortwaves will continue to impinge on the western periphery of the ridge over the weekend, and shower chances are expected to increase in kind. While this gradual pattern shift does favor an overall increase in precipitation chances over the weekend, confidence in the timing details remains is very low, and ensemble probabilities peak at only 30-40% on Sunday. This does leave open a low-end potential (20-30%) for rain on Halloween (Saturday), although currently rain remains slightly favored on the following day. Early next weekend onward, there continues to be in increasing signal for a deeper wave and associated storm system, although cluster analysis reveals drastic differences in the timing and strength of such a system at this time range (8+ days out). While we may not be able to nail down the daily specifics just yet, confidence is relatively high that our current pattern will break down sometime next week, bringing the return of more active weather and increasing rain chances. && .AVIATION /18Z TAFS THROUGH 18Z TUESDAY/... Issued at 114 PM EDT Mon Oct 26 2026 Scattered to broken mid/high clouds will continue across the terminals through the period. Light northeast winds will shift to the east by Wednesday morning. && .MARINE... Issued at 131 PM EDT Mon Oct 26 2026 North-northeast winds are expected to increase to between 15 and 25 kt in the vicinity of Big and Little Sable points early this afternoon, and weaken again gradually this evening and overnight. While a slight offshore wind component will keep the strongest winds and steepest waves in the vicinity of the points themselves, steep waves of 2 to 3 feet should be common in the nearshore waters, with larger waves approaching 5 feet near the points. As such, a Small Craft Advisory has been issued for a brief window from 2 pm to 8 pm today. Winds will weaken and turn even more offshore overnight, allowing waves to settle. Waves are likely to build again late Wednesday and Thursday thanks to breezy onshore southwesterly winds. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory until 8 PM EDT this evening for LMZ848-849. && $$ DISCUSSION...BRC AVIATION...04 MARINE...BRC

NWS GRR Office Area Forecast Discussion