textproduct: Detroit/Pontiac

KEY MESSAGES

- Notably colder conditions today as most areas hold in the 30s with 20s in the Thumb.

- Passing low brings flurries and widely scattered snow showers tonight. Some minor accumulations of a dusting to a few tenths possible mainly in the Saginaw Valley/Thumb.

- Warming trend into the weekend with dry conditions.

AVIATION

High pressure builds into the northern Plains and northern Great Lakes today. The system maintains northerly wind into SE Mi that carries Lake Huron enhanced MVFR stratocu across the area during the morning. Very dry air in northern Ontario gradually takes over across the area leading to decreasing clouds this afternoon. Low clouds are exchanged for increasing high clouds during the evening which thicken and lower as a mid level wave moves in from the upper Midwest. The system also brings widely scattered snow showers mainly in the MBS to FNT area with a diffuse surface cold front. Wind backs briefly toward the west ahead of the front then returns NW with gusts around 20 knots post front as high pressure is reinforced across the region late tonight and Saturday morning.

DTW THRESHOLD PROBABILITIES...

* High for ceiling 5000 ft or less this morning, low this afternoon, moderate tonight.

PREV DISCUSSION

Issued at 320 AM EDT Fri Mar 27 2026

DISCUSSION...

North-northeast flow in place to start the day in the wake of last evening's cold front as upper troughing settles over the Great Lakes. This maintains steady cold advection into SE MI through the day further supplemented by flow off Lake Huron. Result is a downright cold day for the Thumb as highs fall to break freezing, instead ranging 25-30F. Rest of the region only fares slightly better with most areas only topping out in the mid to upper 30s and only limited potential to hit 40F south of M-59.

A partially shearing mid-upper shortwave embedded within the energetic jet across the upper Midwest is set to reach the Great Lakes late this evening before quickly crossing the central Lakes overnight. As it does, a secondary cold front is driven through southern lower MI. Moisture-starved wave lends to lower precip coverage however high-res model soundings advertise sufficient ascent along the 900-700mb frontal slope to support widely scattered snow showers- particularly towards the Tri-Cites/Thumb owing to their proximity to the parent vort max. These northern areas stand the best chance at seeing minor accumulating snow from a quick dusting to a few tenths of inch (for locales that see a snow shower). Otherwise the bulk of the region favored to see only flurries with only isolated, brief light snow showers capable of a dusting at most. Core of thermal troughing follows the front as 850mb temps fall to near -14C and Saturday morning lows bottom out in the lower 20s.

Surface high pressure passes through the Ohio Valley over the course of Saturday shifting local low level flow back to the southwest latter half of the day. Only modest recovery in temperatures occurs Saturday itself as thermal troughing is slowly but steadily eroded with highs remaining in the lower 40s to upper 30s. Low amplitude upper ridging expands over the Great Lakes from the Plains Sunday into Monday maintaining the moderating trend. 850mb temps to return to the mid positive single digits C allowing highs back in the 50s with some 60s possible by Monday. Developing surface low pressure over upper Midwest is then progged to lift a warm front through lower MI Tuesday morning ushering in even milder air, 60s/low 70s, before the arrival of the system's cold front early Wednesday morning. Said low also brings the next chances for some thunderstorms and widespread rain showers.

MARINE...

Moderate northerly wind gradually diminishes during the morning as surface high pressure builds across the northern Great Lakes. The wind direction still supports Small Craft Advisory level waves toward the south end of the lake today. Waves diminish by this evening as winds back NW ahead of a weak reinforcing cold front. This front brings widely scattered snow showers to marine areas tonight followed by an uptick in NW wind Saturday. This direction keeps higher waves more into the open lake until wind diminishes and backs again Saturday night. Wind and waves then remain in check with dry weather Sunday and Monday.

DTX WATCHES/WARNINGS/ADVISORIES

MI...None.

Lake Huron...Small Craft Advisory until 4 PM EDT this afternoon for LHZ421- 441>443.

Small Craft Advisory until 10 AM EDT this morning for LHZ422.

Lake St Clair...None.

Michigan waters of Lake Erie...None.