047 FXUS63 KGRR 081045 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 645 AM EDT Wed Apr 8 2026 .KEY MESSAGES... - Earlier rain chances Thursday; Slight chance of mixed precip Friday - Much warmer Sunday/Monday with periodic chances for rain - Rain chances continue next week while cooling off && .DISCUSSION... Issued at 301 AM EDT Wed Apr 8 2026 - Earlier rain chances Thursday; Slight chance of mixed precip Friday After a cool day on Tuesday, we are watching changes taking place this morning that will bring warmer temperatures to the area today. The transition is marked by the narrow band of precipitation over Eastern Iowa, Southwest Wisconsin, and Northwest Illinois this morning. This is the leading edge of the warmer air aloft that will pushing toward the area this morning. This precipitation, even though could be somewhat wintry with some snow toward Ludington, should not cause any impacts. First of all, moisture below 5k ft is quite limited over our forecast area. This means precipitation rates will be mainly light. Also, ground and road sfc temperatures are above freezing, so the rates should not overcome the relatively warmer ground. This precipitation will move quickly out early this afternoon. The next chance for precipitation now looks focused on tonight, vs. what looked like a late tonight and Thursday morning event yesterday. The cold front with the low that the warm front moving through today is associated with will come in a bit quicker. The NW 2/3rds of the area will see rain tonight, and will be done by 12z Thu. The far SE portion of the area now should see the rain end by noon. This looks to be just a batch of light April showers with less than half an inch or rain expected. This front will get hung up south of the state Thursday night, before a jet streak moves by and interacts with it late Thursday night and Friday morning. This system will mostly be uneventful too, with the caveat that we could see some minor impacts up across our NE counties around daybreak Friday. As the RRQ of the upper jet streak induces the precipitation, the lower levels may be cold enough for the precipitation to be some snow. The NBM blend is not showing this, but many of the Euro ensemble members are. Would not be surprised if a inch or two on grassy areas occurs to the NE of Grand Rapids. - Much warmer Sunday/Monday with periodic chances for rain Saturday we will see a break in the precipitation chances as confluent flow aloft and a fairly strong sfc ridge move over the area. The air behind the Friday system is not that cold, so temps should be mostly in the 50s. We see a somewhat similar setup in the pattern for Sunday as today. Early Sunday, we will see a wing of warm air advection aloft generate some showers that will move quickly to the NE. We will then see warmer temperatures in the wake of this feature, but much warmer than today. We are looking at 850 mb temps warming to around +12C by Sunday afternoon. This would support highs in the 70s away from Lake Michigan with a flow from the SW. The upper flow will remain from the SW on Monday, as will the sfc flow. This will continue to support very warm temperatures for the beginning of April. We will see the moist axis move in, and combine with short wave activity in the SW flow aloft to produce periods of showers and storms. - Rain chances continue next week while cooling off The cold front with this system will push through the area on Tuesday, squashing the very warm temperatures a bit compared to Sunday and Monday. This is the result of the southern periphery of a northern stream short wave pushing the front south. The front will not go far through Wednesday, and will be close enough to allow for shower chances to continue as short wave ride along it just to our south. && .AVIATION /12Z TAFS THROUGH 12Z THURSDAY/... Issued at 645 AM EDT Wed Apr 8 2026 We will be focused on two separate rain events for this morning and Thursday morning, along with gusty winds and low level wind shear. The first batch of precipitation is over Lake Michigan, and approaching the lakeshore. It is weakening as it approaches as it encounters drier air in the lower levels. We do think there will be at least a few sprinkles at KBTL and KAZO, with some light rain at KMKG and KGRR for a couple of hours this morning. KMKG could even see a few snowflakes mix in at the onset. VFR conditions are expected to hold for this event as the low level moisture is just not sufficient to drop conditions below VFR. We will see gusty winds then develop after the rain as skies clear out, and the better gradient settles in. The wind will continue overnight as a 60 knot low level jet moves overhead. We have added low level wind shear to the forecast due to the magnitude of the winds and some directional shear. We will see a band of rain approach KMKG and KGRR late in this forecast period. Again, the rain looks like it will be lacking good low level moisture through 12z, so kept VFR conditions at these sites. Some sub-VFR conditions will be possible after this forecast period. && .MARINE... Issued at 301 AM EDT Wed Apr 8 2026 Gale warning for this morning through Thursday morning continues to look good for areas near and north of Holland, with Small Craft Advisories south of Holland also looking good. Winds will be on the increase this morning, and will continue through tonight with the low level jet moving through tonight. This is a warm air advection pattern, so we will not realize all of the wind at the sfc. It still will be formidable. Once winds and waves diminish Thursday, we will be in for a decent break from the winds and waves for at least a couple of days. Our next marine headline event looks to arrive Saturday night into Sunday ahead of the next system pushing in over the area. && .HYDROLOGY... Issued at 250 PM EDT Tue Apr 7 2026 No significant rain is expected until Wednesday night and Thursday when one quarter of an inch is forecast across the Muskegon Basin with lesser amounts to the south across the Grand and Kalamazoo river basins. This should not have a significant effect on the rivers, where crests from the heavy rainfall last Saturday will continue moving downstream across the rivers. Another wet weather pattern is established early next week and some flooding is possible, && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory from 11 AM this morning to 11 AM EDT Thursday for LMZ844-845. Gale Warning from 11 AM this morning to 11 AM EDT Thursday for LMZ846>849. && $$ DISCUSSION...NJJ AVIATION...NJJ MARINE...NJJ HYDROLOGY...Ostuno

NWS GRR Office Area Forecast Discussion