724 FXUS63 KGRR 271042 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 642 AM EDT Tue Oct 27 2026 .KEY MESSAGES... - Warming Up Into Wednesday - Rain Chances Return Thursday - Additional Rain Chances This Weekend into Next Week && .DISCUSSION... Issued at 209 AM EDT Tue Oct 27 2026 - Warming Up Into Wednesday Weak divergence and positive vorticity advection will keep the mostly cloudy skies in place into Wednesday morning. Southwest flow builds into Wednesday bringing warmer temperatures. Highs today in the mid 50s (north) to mid 60s (south) will increase into the upper 60s to low 70s for Wednesday. - Rain Chances Return Thursday The low level jet and increased moisture move in late Wednesday night into Thursday bringing a chance for light rain to the area. Best chances (60 to 90 percent) will be along the lakeshore Thursday morning and afternoon. Probabilities for a tenth of an inch or more are only 20 to 30 percent, therefore amounts should be light. There is a slight hint for some instability, therefore an isolated rumble of thunder can`t be ruled out. Dry conditions move in for Friday with cooler temperatures in the 60s. - Additional Rain Chances This Weekend into Next Week The overall pattern varies as seen in the cluster analysis heading into the weekend and next week. Ensembles show chances increasing Saturday (20 to 30 percent) into Sunday (40 to 50 percent). Saturday could be hit and miss as there is a question as to how fast the dry air erodes. Based on ensembles any rain Saturday would be light if it occurs. As mentioned in the previous discussion, there continues to be a signal for a deeper wave and associated storm system early next week. However the exact timing, strength, and placement of the low are uncertain. This is seen in the different long range ensemble clusters. Where they do agree, is periods of rain are expected for next week. Confidence in forecast will increase as we get closer with observations sampling the incoming pattern better. && .AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/... Issued at 642 AM EDT Tue Oct 27 2026 VFR conditions are expected with easterly winds becoming southeasterly later this morning. Gusts toward 20 knots are possible with the best chances along the lakeshore. Southeast to south winds become light tonight into Wednesday morning. && .MARINE... Issued at 209 AM EDT Tue Oct 27 2026 Easterly winds turn to the southeast later this morning. Isolated gusts to 25 knots are possible during the morning and and early afternoon, but waves will remain around a foot or less. These isolated gusts are not expected to be widespread, therefore have held off issuing a Small Craft Advisory. If gusts become more widespread and persistent then an Advisory will be needed. Southwest winds develop for Wednesday and build Wednesday night into Thursday ahead of a weak front. Gusts may approach 25 knots with wave heights around 3 to 5 feet. Behind the front Thursday evening into Friday, light northerly winds move in. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...None. && $$ DISCUSSION...RAH AVIATION...RAH MARINE...RAH

NWS GRR Office Area Forecast Discussion