textproduct: Detroit/Pontiac

KEY MESSAGES

- High-end to likely chances (50-60%) for snow showers tomorrow morning to early afternoon. Snow accumulations hold under an inch, likely a dusting to a half-inch.

- Below normal temperatures persist through most of the week.

- Next likely chance for snow enters Thursday night through Friday.

DISCUSSION

A ridge axis has maintained dry and stable conditions across the Great Lakes, which has brought a full day of sunshine. This has allowed temperatures to warm up into the low to mid 20s across SE MI. Flow remains quasi-barotropic with only modest/delayed cold advection, the peak which arrives after peak radiational cooling. As a result, overnight lows will still be very cold, but not as cold as this morning, with temperatures ranging between the low to upper single digits.

A shortwave and extended lobe of vorticity now exiting the plains will enter the Great Lakes tomorrow morning which will bring higher end to likely chances (50-60%) for light snow. The antecedent dry environment and weak forcing precludes any meaningful snow accumulation with totals holding under an inch, likely ranging between a dusting up to a half-inch between 12Z to 18Z as the feature progresses from west to east. Low-level flow will veer west in the wake of the shortwave which will introduce some additional lake effect snow chances through tomorrow afternoon and evening.

Both the thermodynamic environment and resulting lake-induced instability off of Lake Michigan appear less supportive than yesterday, which lowers confidence regarding any meaningful accumulation from lake effect snow showers after 18Z. However, increasing subsidence in the mid-levels in the wake of the departing wave can squeeze out flurries through the day. A better response and opportunity for some better snow showers with brief accumulation will be across the Tri-Cities and Thumb Tuesday morning, tied to progression of a secondary shortwave across northern lower and the continued veering of wind direction to the northwest. This will enhance convergence along a weak cold front, which will become more diffuse as it progresses south of I-69. Continued chance for flurries or very light snow will exist through Tuesday but moisture quality through 5kft will be poor which again limits confidence for accumulation. Daytime highs peak in the mid 20s for Tuesday.

High pressure to gradually fill back in Wednesday and Thursday which will bring dry conditions along with a persistence forecast with highs in the 20s and lows in the single digits. The next likely (60- 70%) chance for snow enters late Thursday night into Friday as a clipper system drops. Pending the final track of this system, there will be a brief opportunity for milder air across the Plains to advect in ahead of this system, bringing chances to see temperatures near the freezing mark. NBM probabilistic data remains steady for 50-70% chances to see at least 1" of snow with this system. Enhancement of the trough in the wake of this system will bring the return of well below normal temperatures. Lows near zero and highs in the teens are forecasted for the start of the weekend.

MARINE

Influence of high pressure maintains light (<15kt) winds to close out the weekend. A weak clipper arrives late day Monday but aside for scattered light snow showers, brings minimal marine impacts with accompanying winds holding at or below 20kts. Another high dropping out of the upper Midwest then follows for midweek bringing quiet marine weather.

PREV DISCUSSION

Issued at 1219 PM EST Sun Feb 1 2026

AVIATION...

Stretch of generally dry and stable conditions will persist through tonight. Passage of a surface ridge will result in a wind shift from northwest to southwest during the latter half of the day. This may draw a lingering area of MVFR cloud cover off lake Michigan into mainly MBS at times through tonight. Otherwise, mainly clear skies favored until high based cloud arrives late tonight associated with an inbound mid level disturbance. This system will bring a chance of light snow starting during the latter half of Monday morning.

DTW THRESHOLD PROBABILITIES...

* Low for cigs at or below 5000 ft late tonight. High Monday.

* High for ptype as snow Monday.

DTX WATCHES/WARNINGS/ADVISORIES

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