940 FXUS63 KGRR 031106 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 706 AM EDT Fri Apr 3 2026 .KEY MESSAGES... - Additional Showers and Storms Tonight into Saturday - Turning Colder from Sunday into Tuesday - Additional Rainfall in the Latter Half of the Work Week && .DISCUSSION... Issued at 404 AM EDT Fri Apr 3 2026 - Additional Showers and Storms Tonight into Saturday Another round of showers and thunderstorms is expected from tonight into Saturday as a warm front lifts back northward into the area. A low level jet will accompany the front which will bring the a very moist airmass for this time of year back into the area. Additional rainfall will be on the order of a half to one inch (See hydro section below). Surface dew points will surge to around 60F once again as the warm sector slides through our southern CWA (south of a Holland to Alma line). Given a potent upper shortwave trough swinging through and plenty of moisture showers and thunderstorms are likely. Cannot rule out a few stronger storms in Southern Lower Michigan from overnight tonight into early afternoon on Saturday when the moisture and instability is shunted east with the front. - Turning Colder from Sunday into Tuesday We turn colder behind the Saturday system with 850mb temperatures falling to -7C to -10C on Sunday. These values may be just cold enough for a little bit of lake effect snow. Highs will be in the low to mid 40s all three days. - Additional Rainfall in the Latter Half of the Work Week We warm up late in the work week with chances for rain returning to the forecast. 50s for highs look common late in the week and into the weekend. which is normal for this time of year. A cold front moves into the area Thursday and then stalls out into Friday and Saturday. We could be looking at another wet period. && .AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... Issued at 706 AM EDT Fri Apr 3 2026 Ceilings range from MVFR to VFR across the TAF sites at 12z. A trend to VFR conditions is expected this afternoon in the wake of a cold frontal passage this morning. The front will lift back north as a warm front tonight and showers and thunderstorms will move back in overnight. A deteriorating trend will occur overnight in aviation conditions with a dip back to MVFR and IFR. && .MARINE... Issued at 404 AM EDT Fri Apr 3 2026 Waves remain up this morning due to the strong south winds of the past 24 hours. Winds have veered to the southwest this morning and will continue that trend to the west today. Wind speeds will come down considerable and therefore waves will slowly drop as well. We expect waves to be below 4 feet by 200pm, so the current expiration time of the Small Craft Advisory looks good. Waves will increase once again over the weekend as cold air advection takes hold behind the passage of a low. && .HYDROLOGY... Issued at 404 AM EDT Fri Apr 3 2026 Rainfall totals thus far based on MRMS radar estimates range from 0.75 to above 2.00 inches in narrow swaths (such as across portions of Allegan and Oceana Counties). Overall the round of rain that occurred in in the past 24 hours or so went down about as expected. Rises have commenced on area rivers with some forecast to rise above bankfull but remain below flood stage. As for some ground truth, WFO Grand Rapids saw 0.96 inches and Muskegon had 1.37 inches which was a record for the day. We will know more today in terms of forecast river levels as yesterday`s rainfall is routed through the river systems and additional forecast rain is added to the modeling. The new precipitation that will be added ranges from around a half inch to an inch which will result in additional rises. We currently have a Flood Watch out from both Bridgeton and Newaygo on the Muskegon. Not out of the realm of possibilities to see a few River Flood Warnings issued over the coming days, but a widespread river flood event is not expected. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory until 2 PM EDT this afternoon for LMZ844>849. && $$ DISCUSSION...Duke AVIATION...Duke MARINE...Duke HYDROLOGY...Duke

NWS GRR Office Area Forecast Discussion