textproduct: Detroit/Pontiac

KEY MESSAGES

- Warmer today and tomorrow with highs to around 80 degrees.

- Chance of showers with isolated thunderstorms tonight.

- More typical fall weather mid to late week.

DTW THRESHOLD PROBABILITIES

* Low in visibilities and/or ceilings aob 1/2SM and/or 200 feet this morning.

PREV DISCUSSION

Issued at 340 AM EDT Mon Oct 12 2026

DISCUSSION...

Notable inversion on the 00Z DTX RAOB last evening has low level moisture trapped across southeast Michigan. Low stratus has been slow to clear along and east of the glacial ridge, but the back edge of this cloud shield is slowly creeping east through the early morning hours. To the west of this cloud deck is clear skies and favorable environment for fog development with many observations now showing visibility down to 1/2 mile or less. Will monitor the visibility trends that could necessitate a dense fog advisory.

Any fog across southeast Michigan is expected to dissipate by 15Z this morning. Brief residence time of shortwave ridge today with a surface high pressure to the south will strengthen southwest low level flow and commence strong warm air advection into this afternoon. Temperatures at 850 mb are forecast to be around 15C this afternoon and good insolation under mostly clear skies will allow high temperatures to reach the upper 70s to low 80s. Strengthening LLJ winds will drive increasing moist isentropic ascent over Michigan tonight as a weak low pressure moves along a cold frontal boundary draped across the upper Midwest. This will lead to the development of showers that will move across a good portion of southeast Michigan during the overnight hours. There will be just enough elevated instability to support isolated general thunderstorms.

Surface low forecast to track across northern lower Michigan on Tuesday. Southwest to west flow will draw in slightly warmer air while allowing the mild airmass to persist throughout the day. Expecting 850 mb temperatures to climb a 2-3 more degrees compared to today with mid-upper level drying bringing a period of reduced clouds. This should help temperatures a little higher into the low 80s for much of the area with mid 80s achievable towards the southern MI border ahead of the approaching front. The cold front is expected to pass through late Tuesday and offer a low chance for additional shower activity, though better chances will reside to the north.

Another chance for precipitation will occur Tuesday night into Wednesday as a shortwave is forecast to lift across the lingering frontal zone. Activity will be more focused south of I-69 corridor of southeast Michigan into the Wednesday afternoon period and come to an end by Wednesday evening. Wednesday will also begin the transition back to more typical fall like conditions that carry into the late week. Higher amplitude ridging will build across the Intermountain West during this time with a downstream strengthening Canadian trough combining with a southern stream wave. Another round of deeper moisture with ties to the gulf will lead to widespread precipitation with periods of steadier rainfall supported by the greater dynamic setup moving over the Great Lakes. In the wake of this system will be strong cold air advection that will result in a cool start to the weekend. Saturday morning lows will fall towards freezing with daytime high temperatures topping out in the low-mid 50s. It does appear though that temperatures will recover back towards more normal values Sunday into early next week.

MARINE...

A ridge of high pressure to briefly fill in across the Great Lakes this morning which will support lighter winds for most of the day. A weak low pressure system will then move from the central Plains into northern lower Michigan by tomorrow morning. Some slightly elevated wind gusts around 20 knots will be possible across northern Lake Huron with the arrival of this system, along with rain and isolated thunderstorm chances. A cold front will then push through on Wednesday morning, bringing additional chances for precipitation. Northwest flow in the wake of the front will support another round of gust potential at or above 20 knots across northern Lake Huron on Wednesday.

DTX WATCHES/WARNINGS/ADVISORIES

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