textproduct: Detroit/Pontiac

KEY MESSAGES

- Dry and warm through tomorrow. - Periods of scattered to numerous rain showers with some embedded thunderstorms likely Friday into Saturday.

DTW THRESHOLD PROBABILITIES

* None.

PREV DISCUSSION

Issued at 343 PM EDT Wed Jun 3 2026

DISCUSSION...

A seasonably strong 1027mb high pressure system now over the southern Great Lakes and Ohio River Valley will expand into the Appalachia region tonight into tomorrow in response to the breakdown of the longwave ridge across the central CONUS. The closed low across the northern Rockies has started to carve into the ridge as it travels eastward, ahead of the arrival of a Pacific NW trough. This brings continued stability across SE MI which will sustain dry weather tonight and tomorrow. Temperatures now in the low 80s cool into the mid 50s overnight under mostly clear skies. The slight increase in magnitude of southwest flow will stream the warmer temperatures across the Plains into Michigan, pushing highs into the mid to upper 80s tomorrow. Outside of periodic translucent cirrus through the day and what will likely be a meager attempt at few-sct cu development given limited moisture in the column.

The streak of dry weather will end Friday into Saturday as a series of shortwave troughs move across the state bringing high-end chances for multiple rounds of rain showers with embedded thunderstorms. Weak upper-jet structure along with poor amplitude of the trough and moderated baroclinicity precludes any strong mention of severe thunderstorm potential. Global models do highlight 0-6km shear values around 30 knots aligned with 500-1000 J/kg CAPE during the afternoon hours, so cannot totally rule out some stronger storm potential. This will be highly dictated on prior day/morning activity rain and cloud cover, but bears watching once within the hi- res output window.

The last of the upper-level waves will depart on Sunday bringing mostly dry conditions to start the week, outside of some very low chances for a pop-up afternoon shower under a weakly capped environment for Sunday. An upper low across Texas will open and travel north into the Midwest early next week which will aid in the development of a strong ridge across Michigan on Monday, bringing dry conditions. Confidence then turns much lower regarding potential duration of dry weather along with above normal temperatures and will be pending the speed of the upper-level ridge along with the associated high pressure system just east of the ridge axis. The latest PoP values hold aob 20% Tue-Wed which would allow highs to push into the upper 80s assuming the dry forecast. Latest 12Z ECMWF and AIFS (including time lagged 24 hr AIFS) highlight the potential for early breakdown of the ridge, bringing shower and thunderstorm chances Tue-Wed. This scenario would cap highs in the low to mid 80s.

MARINE...

A high pressure system continues to sit atop the Great Lakes region today into tomorrow morning. This high pressure system is then expected to deteriorate during the early afternoon hours as a low pressure system approaches the area. Light wind flow is expected to shift overnight from southernly to southeasterly in all regions. Thursday evening the coast of Lake Erie will have light winds varying from the southeast to southwest. Southern Lake Huron and Lake St. Clair will experience relatively light winds out of the south Thursday evening into the morning hours. Saginaw Bay will experience more moderate southwesterly winds Thursday afternoon into the overnight hours, with wind gusts up to 20 knots possible. North Lake Huron is expected to have moderate winds as well from the south, with gusts upwards of 25 knots possible, in the afternoon hours, with a gradual shift to lighter winds and more southwesterly flow expected overnight Thursday into Friday morning.

Winds are expected to be modest out of the southwest Friday for the shore of Lake Erie, Lake St. Clair, and Southern Lake Huron, with gusts up to 20 knots possible. Saginaw Bay is also expected to have modest flow out of the southwest, with persistent winds of up to 20 knots possible, along with gusts of up to 25 knots possible as well. North Lake Huron is expected to have relatively calmer winds out of the south Friday, with gusts of 20 knots possible closer to the shore.

Light winds are expected to shift from southwesterly to northernly Saturday in the Lake Huron area, with gusts of up to 20 knots possible in the bay area. Lake St. Claire and the coast of Lake Erie are expected to gradually shift from southwesterly to westerly flow Saturday, with gusts of 20 knots possible in the morning hours.

Rain showers are expected for all regions Friday evening as a cold front associated with this low pressure system treks across the Great Lakes region. Scattered showers are possible throughout the day Saturday as this low pressure system departs our area. Thunderstorms cannot be ruled out either.

DTX WATCHES/WARNINGS/ADVISORIES

MI...None. Lake Huron...None. Lake St Clair...None. Michigan waters of Lake Erie...None.