607 FXUS63 KGRR 251032 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 632 AM EDT Mon May 25 2026 .KEY MESSAGES... - The only chance of rain with a backdoor cold front Wednesday - Mild temperatures and dry conditions Thursday and beyond && .DISCUSSION... Issued at 228 AM EDT Mon May 25 2026 - The only chance of rain with a backdoor cold front Wednesday The Dense Fog Advisory issued last evening is working out very well, with most observations showing 1/4 mile visibilities, and the night time microphysics satellite imagery showing lots of low clouds and fog. This will burn off quickly after sunrise, so no concerns there. Otherwise today and Tuesday, we should see a good deal of sunshine with just a few high clouds expected. We will remain in between the northern stream well north of the area, and the deeper and more rich moisture just to our south. The Northern stream will send a back door cold front down through the forecast area on Wednesday. This is in response the the upper ridge axis just west of the area, and the cold front to slide down downstream of the ridge where NNE aloft dominates. It does look like precipitation trends have increased a little with this front over the last 1-2 days. Moisture and resultant instability will be limited with deep moisture locked up just south of the state. The best chance of rain with this weak front will be a bit inland from Lake Michigan, which will stabilize the lakeshore a bit with a flow from the SW. - Mild temperatures and dry conditions Thursday and beyond 850 mb temperatures will fall from +15 to +16C on Tuesday, to around +9C by Wednesday evening behind the front. Instead of max temps inching up to the 80s, this cold front will keep highs in the 70s through the week. The upper ridge axis will end up just west of the area and will block up the major weather features. For our area, it means mild temperatures and a good deal of sunshine through the end of the forecast period. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 632 AM EDT Mon May 25 2026 Fairly widespread dense fog in the VLIFR category remains at just about all of the forecast terminals early this morning. KJXN is not quite as bad, likely due to some local effects from the Irish Hills. All sites will see a quick improvement this morning as sunshine will dissipate it quickly. It may take a tad longer at KLAN due to it being thicker per satellite trends. After the fog burns off, no other concerns today as not many clouds are expected. Fog is not likely tonight after a good day of drying occurs, and some wind remains up tonight. && .MARINE... Issued at 228 AM EDT Mon May 25 2026 Night time microphysics satellite imagery this morning shows widespread stratus/fog over the lake. This continues to justify the Marine Dense Fog Advisory well. Chances are this will linger longer over the lake due to less mixing, so it may need to be extended a bit this morning. Other than the Fog advisory, we continue to think that no other wind/wave headlines will be needed over the next week. This comes as we will only see one system move through (Wednesday) with limited wind associated with it. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...Dense Fog Advisory until 11 AM EDT this morning for MIZ037>040- 043>046-050>052-056>059-064>067-071>074. MARINE...Dense Fog Advisory until 10 AM EDT this morning for LMZ844>849. && $$ DISCUSSION...NJJ AVIATION...NJJ MARINE...NJJ

NWS GRR Office Area Forecast Discussion