990 FXUS63 KGRR 031045 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 645 AM EDT Mon Aug 3 2026 .KEY MESSAGES... - Mostly Sunny into Tuesday - Showers and Thunderstorms Possible Tuesday Night into Friday && .DISCUSSION... Issued at 210 AM EDT Mon Aug 3 2026 - Mostly Sunny into Tuesday Pressure heights increase as the mid level ridge moves overhead along with the surface high. Mostly sunny skies and light winds are expected. A lake breeze develops this afternoon with westerly winds pushing inland. Winds will be more southwesterly Tuesday ahead of our next chance for rain. Highs in the mid 70s to mid 80s are expected with lows in the 50s with a couple spots north of US-10 potentially dropping into the upper 40s. - Showers and Thunderstorms Possible Tuesday Night into Friday A broad upper level trough moves in mid week with heights beginning to lower Tuesday night. Overall showers Tuesday night may remain just north and west of the forecast area until better forcing and moisture moves in Wednesday morning. The trough axis and surface front will be slow moving in and out of the area. A lull in showers is possible Wednesday afternoon before another round of positive vorticity advection moves through Wednesday night into Thursday morning. Instability is limited, mean values around 500 J/kg or less, and shear is weak. Therefore the potential for severe thunderstorms is low. Dry conditions slowly move in Thursday night into Friday behind the front. There is the potential for shower and thunderstorm chances to linger into the weekend looking at ensembles. Within the broad trough in southwest to west flow we do not clear out the instability and moisture in the area. However confidence is not high enough to add PoPs into the forecast this far out. With no significant source of lift, most if not all could remain dry. Temperatures will continue to be in the 70s to 80s during the day with overnight lows in the 50s and 60s. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 645 AM EDT Mon Aug 3 2026 Shallow ground fog is impacting the area and reducing visibilities this morning. With the patchy and shallow nature of the fog, it should burn off quickly this morning. Light and variable winds are expected throughout the day. A lake breeze develops this afternoon with west winds pushing further east into western Michigan. Some diurnal cumulus around 3500 to 4500 feet is expected today. Another round of shallow ground fog is possible again tonight into Tuesday morning. && .MARINE... Issued at 210 AM EDT Mon Aug 3 2026 The South Haven buoy wave height readings continue to fall as winds become light and variable. With waves now below 4 feet and falling to around 1 foot this morning have cancelled the Small Craft Advisory and Beach Hazard Statement. High pressure will bring light winds and low wave heights into Tuesday. Water temperatures will be in the 50s with some spots in the 40s. Winds then shift to the southwest Tuesday and may approach Small Craft Advisory thresholds north of Grand Haven with wave heights 1 to 3 feet. Winds and waves are then expected to remain below Small Craft Advisory and Beach Hazard Statement levels through the rest of the week. Thunderstorms are possible late Tuesday night into Thursday. The threat for severe storms is low. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...None. && $$ DISCUSSION...RAH AVIATION...RAH MARINE...RAH

NWS GRR Office Area Forecast Discussion