textproduct: Detroit/Pontiac

KEY MESSAGES

- Warming trend Wednesday with temperatures in the 70s.

- Mainly dry conditions with seasonable temperatures Thursday and Friday.

- Turning warmer again next weekend.

DTW THRESHOLD PROBABILITIES

* Low for ceiling at or below 5000 feet Wednesday.

PREV DISCUSSION

Issued at 257 PM EDT Tue Oct 6 2026

DISCUSSION...

Notably milder conditions arrive tonight, established within a meaningful window of warm air advection under persistent low level southwest flow. This pattern emerging within the immediate downstream moderating warm sector ahead of an inbound cold front set to arrive Wednesday. This in combination with periodic thicker mid level cloud lends to low temperatures Wednesday morning arriving a solid +10-15 degrees warmer than that noted this morning. Existing system relative isentropic ascent lacks in greater moisture quality, while better forcing remains displaced to the north. There remains a small subset of the model solution space that offer a lower probability for a few widely scattered showers/sprinkles to develop overnight, mainly across the Saginaw Bay region and northern thumb.

Modest height falls emanating south of a closed system lifting thru Hudson Bay will draw the associated lead cold front across southeast Michigan Wednesday. Limited moisture quality and lack of larger scale dynamics or frontal convergence still suggest a dry frontal passage. Daytime heating effectively counters any meaningful initial cold air advection during the diurnal heating cycle. This will allow highs to push into the lower to middle 70s. Some modest late day gustiness to the post-frontal westerly wind. Secondary stronger cold frontal passage set for Wednesday night as the main vorticity lobe glances across the northern great lakes. This may again offer a lower probability for shower production mainly north of I-69 during the overnight hours. Outgoing forecast holding with dry conditions at this stage.

Broad, high-latitude surface ridge centered near northern Ontario will expand southward into the Great Lakes basin Thursday, becoming fully entrenched over Southeast Michigan Thursday night into Friday. The deep layer stability held within this environment affords dry conditions to finish the work week. Coolest conditions Thursday as 850 mb temps dip into the lower single digits within the immediate post-frontal environment. Strong radiational cooling prospects Thursday night likely bring low temperatures back into the 30s for some locations. Strengthening southerly flow within the background of an aggressive increase in upper level heights will then lead to a more significant warming trend for this weekend. This will push temperatures well above early October normals by Sunday as readings climb well into the 70s. Strong ridging aloft ensures dry conditions through at least the first half of the weekend. Attention for the back half of the weekend will focus on behavior of a deeper plume of moisture currently projected to accompany a stronger mid level circulation out of the western gulf. An upward revision in forecast precipitation chances plausible Sunday as confidence in system trajectory improves.

MARINE...

South-southwest winds strengthen this evening into tonight as the northern Ontario low pressure tracks closer tightening the local gradient. Ongoing warm advection acts as a limiting factor to peak wind gusts with both model soundings and local probabilistic guidance being fairly low on gale potential (<20%). Given the longer fetch across central/north-central Lake Huron, can't rule out a few gusts to low-end gales early tonight but winds are expected to peak more in the low 30kt range. As such, will continue to hold off on any Gale Warnings. Small Craft Advisories remain in effect through Wednesday morning for the Saginaw Bay/Port Austin waters due to these winds and subsequent waves. Surface cold front eventually crosses Wednesday flipping flow to the northwest with persistent James Bay troughing maintaining moderate gusts (20-30kts) through Thursday.

DTX WATCHES/WARNINGS/ADVISORIES

MI...None. Lake Huron...Small Craft Advisory until 10 AM EDT Wednesday for LHZ421-422-441.

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