377 FXUS63 KGRR 051743 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 1243 PM EST Thu Mar 5 2026 .KEY MESSAGES... - Cloudy with Rain Showers Today - Periods of Rain and Thunderstorms Friday into Early Saturday - Above Normal Temperatures Until Mid-Week System && .DISCUSSION... Issued at 250 AM EST Thu Mar 5 2026 - Cloudy with Rain Showers Today Low pressure with plenty of low level moisture will result in cloudy conditions with rain showers through this afternoon. A few rumbles of thunder are possible south of I-94 this afternoon as there will be some instability as the upper level low moves through. Although our main source of lift exits the region this evening, soundings show low level moisture sticking around. Wouldn`t be surprised if patchy drizzle was present overnight into early Friday. Temperatures today will be a cooler due to the cloud cover, rain, and northeast flow. - Periods of Rain and Thunderstorms Friday into Early Saturday The previously mentioned low level moisture may delay how fast CAPE builds through the day Friday limiting the thunderstorm potential until later. The low level jet moves in Friday afternoon bringing low level convergence along with warm air advection. It is with this lift we have our first initial chance for showers and thunderstorms, although not expecting any strong to severe storms with this initial round. Instability builds through the remainder of the day into Friday night along with the strengthening low level jet of around 60 knots. There will be plenty of wind shear into Saturday morning along with 0-3km storm relative helicity. This is leading to the marginal severe risk highlighted by the SPC Friday night into Saturday morning. There still remains some uncertainty with the overall timing of an anticipated line of thunderstorms that is expected to move through Saturday morning. This will impact how much instability is available as well. Some solutions have a better set up for severe storms, while others are less favorable. Keep up to date with the latest forecast as we get closer. - Above Normal Temperatures Until Mid-Week System Normal high temperatures this time of year are typically in the upper 30s to low 40s and after today highs are forecast to be in the 50s and 60s with some spots potentially approaching 70 into next week. Currently there is a chance to break record high temperatures in some spots Friday and Monday along with record warm low temperatures Saturday and Tuesday. As with any spring pattern however, there is agreement in the long range ensembles with colder temperatures moving in behind a system mid week. Rain chances increase Tuesday into Wednesday with a transition to snow possible as the colder air moves in Wednesday night. && .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/... Issued at 1243 PM EST Thu Mar 5 2026 IFR and lower conditions with low clouds and fog will dominate this entire forecast period. We are starting out of the gate with rain impacting all terminals except KGRR and KMKG, where drizzle/low clouds are still in place. We will see the rain move out of the area, and conditions may improve slightly this afternoon. Visibilities have a better chance of going to MVFR, but ceilings are expected to stay IFR. After dark, we will see winds go light across the area. This and surface cooling will only support conditions deteriorating. The I-94 terminals are likely to see it drop quicker and lower being closer to the front just south of the area. All sites should go to LIFR to VLIFR between 03-06z and stay down the rest of the night. There may be some slight improvement right at the end of this period. Storms may approach right at the end of the period, but that is more likely after this forecast period. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...None. && $$ DISCUSSION...RAH AVIATION...NJJ

NWS GRR Office Area Forecast Discussion