FXUS63 KDTX 062308 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 708 PM EDT Wed May 6 2026 .KEY MESSAGES... - A Frost Advisory is in effect for most of SE Michigan outside metro Detroit where lows drop into the 30s tonight. - Mainly dry tonight and Thursday, but isolated late afternoon and/or evening showers are possible. - Temperatures recover over the weekend with potential for showers and thunderstorms. && .AVIATION... Favorable aviation weather is highlighted by a gradual cloud decrease and light westerly wind tonight followed by a return of VFR clouds mostly above 5000 ft Thursday afternoon. This cloud response is tied to the next in a series of smaller scale mid level circulations that move overhead around the southern fringe of the large Hudson Bay trough that holds position through late week. A boost from renewed afternoon instability results in broken to overcast VFR ceiling that lingers into Thursday evening. D21/DTW Convection...No thunderstorms expected through Thursday. .DTW THRESHOLD PROBABILITIES... * None && .PREV DISCUSSION... Issued at 316 PM EDT Wed May 6 2026 DISCUSSION... Numerous shortwaves observed via mid level water vapor imagery this afternoon, stretching from the northern Plains into northern Manitoba. These waves are embedded within the larger scale troughing pattern that surrounds a closed Hudson Bay low and will be responsible for below normal temperatures and an unsettled/low predictability pattern through the weekend. Visible satellite imagery shows healthy coverage of diurnal cu this afternoon, while high cloud filters in aloft in the presence of a strengthening ~150 knot jet streak that is pushing into the Ohio Valley. A band of virga is observed via MRMS composite radar at the nose of the jet streak, although the 12z KDTX RAOB and subsequent forecast soundings depict a deep layer of mid-level dry air to prevent this from reaching the ground. Nonetheless, cannot completely rule out a stray shower this evening mainly as the lead shortwave pivots across the Great Lakes and briefly moistens the mid- levels. Loss of diurnal heating and negative vorticity advection allow clearing for a few hours before daybreak which sets up a period of radiative cooling. This aligns with the arrival of the thermal trough in which h8 temperatures drop to -5 to -10 C, with forecast lows in the mid-30s. A Frost Advisory has been issued for most of SE Michigan as a result. Thursday forecast will be similar to today, with below normal temperatures only in the mid 50s even with pockets of solar insolation in the morning. Inverted-V soundings suggest another dry day, even with slightly deeper boundary layer moisture and diurnal cloud development. Lower predictability in the pattern exists Thursday night into the weekend as the embedded waves over Canada release into the Great Lakes. Deep moisture will still be hard to come by given the northern stream influence aloft, although gradual moisture improvements are expected in the low levels as the surface high drifts toward the mid-Atlantic and return flow develops upstream. Lead edge of warm advection arrives Thursday night, creating the next chance for showers and bringing a warmer airmass into the region Friday (low 60s)-Saturday (upper 60s). A more focused opportunity for showers and thunderstorms arrives this weekend as a cold front sweeps across SE Michigan. Enhancements to the low level jet ahead of the front will lead to breezy southwest flow Saturday. Drier and cooler conditions then return for early next week in the post- frontal regime. MARINE... Minimal marine concerns in the next few days as we are locked in with a broad upper level trough through that time. Weak pressure gradient at the surface will keep winds light, generally under 20 knots through Friday. There will be several weak systems over the region during this time as well but really only amounting to low chances of precipitation. The next notable cold front will come through on Saturday bringing increased winds and thunderstorm chances. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...Frost Advisory from midnight tonight to 8 AM EDT Thursday for MIZ047>049-053>055-060>063-068-069-075-082. Lake Huron...None. Lake St Clair...None. Michigan waters of Lake Erie...None. && $$ AVIATION.....BT DISCUSSION...MV MARINE.......DRK You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.