textproduct: Detroit/Pontiac

KEY MESSAGES

- Areas of fog/freezing fog can be locally dense this morning.

- Above normal temperatures continue through mid week.

- The next round of precipitation is on schedule for Tuesday night and Wednesday. All rain is expected with decreasing potential for wintry mix across the north.

- A rain/snow mix moves in by Friday followed by a temperature drop back toward mid/late February normals this weekend.

UPDATE

As increasing southwest flow and diurnal mixing work toward eroding the very deep near surface based inversion shown on the 12Z DTX sounding, temperatures will undergo a rapid warming trend heading into mid-late afternoon. The southwest flow today will actually drive 925mb temps up toward +10C by late afternoon. This degree of warm air this time of year, especially with a melting snow pack and frozen ground, typically raises uncertainty as to just how effective the mixing will be. Given the southwest winds, any slight over achievement of mixing could push daytime temps toward the 60 degree mark away from the lakes. The melting snow will warrant giving pause on such warm afternoon temps. However, in light of recent hi res solutions, a forecast update will be issued to nudge afternoon temps up a couple degrees.

A brief duration of good mid level isentropic ascent tied to a short wave tracking across the northern great lakes will slide across the northern thumb late this afternoon, warranting the current low chance pops.

PREV DISCUSSION

Issued at 524 AM EST Mon Feb 16 2026

AVIATION...

Calm to light winds under a nocturnal inversion will continue to promote a stagnant environment which will maintain the mvfr-ifr haze prior to daybreak. Localized dense fog chances will be most probable across KDET due to subtle lake moisture enhancement, which may bring some LIFR visibility restriction. Through the late morning, the low levels will start to mix out as light southwest winds take hold, which will improve visibilities to VFR. VFR conditions are then expected through the remainder of the day under periodic mid to high level clouds. Haze or fog development will again be possible tomorrow morning.

DTW THRESHOLD PROBABILITIES...

* Low for cig/vsby below 200ft and/or 1/2SM this morning.

PREV DISCUSSION... Issued at 342 AM EST Mon Feb 16 2026

DISCUSSION...

Areas of fog across SE Mi are most favored to be locally dense toward the Great Lakes shorelines where high clouds remain thin and wind is calm. Melting snow over the last few days is also keeping the boundary layer primed with moisture to sustain fog and haze through mid morning before SW wind increases across the region. High clouds are then on the increase out ahead of the next short wave system moving in from central Canada and the Midwest. Primary low pressure is well north into Ontario with a more subtle surface reflection along the southward extending cold front that moves into northern Lower Mi this afternoon. Increasing SW flow ahead of the surface wave ensures another day of temperatures well above normal. Highs in the lower 50s look reachable even with a greater cloud component compared to recent days. The clouds are within a ridge of higher moisture that builds in ahead of the surface low and cold front that moves into SE Mi this afternoon. There is a chance that moisture transport and isentropic ascent become adequate for some light rain to graze the Tri Cities and northern Thumb, however the bulk of precipitation occurs farther north where combined short wave support is greater. The trailing cold front moves in this evening and is expected to be a dry passage through SE Mi to the Ohio border by sunrise Tuesday.

Temperatures are held more in check Tuesday as the front stalls nearby to the south of the Ohio border. There is a substantial cloud component across Lower Mi along with easterly surface wind which combine to hold temperatures in the 30s along the Lake Huron shoreline increasing to mid 40s interior west of I-75/US-23. The new 16/00Z model runs are in good agreement on the maintenance of dry weather otherwise during the day as the 500 mb ridge axis moves overhead in advance of the well-advertised mid week low pressure system. This system activates the stalled front in textbook fashion Tuesday night as the surface low grows to cover much of the northern Plains. Model data indicate a 50 kt low level jet reaching into the Ohio valley with a generous supply of Gulf modified air to feed an all rain event for SE Mi. There are no big changes in the model treatment of this system in terms of track or evolution which maintains similar QPF expectations to the last few forecast cycles. Strong transport of Gulf modified air focused into the warm front across southern Lower Mi results in higher end rainfall totals for this time of year. Consensus of deterministic and AI runs offer a fairly coherent QPF axis across northern Lower Mi with the southern fringe across the northern Thumb and Tri Cities where totals reach the 0.5 to 0.75 inch range before the mid level dry slot quickly cuts off activity Wednesday afternoon. The northern Thumb is also still slightly vulnerable to a brief period of freezing rain at onset, however temperatures are projected to rise well above freezing as rainfall rate peaks after midnight. The warm sector of the system surges more strongly into the area south of I-69 by Wednesday afternoon, and this is where high temperatures likely reach the lower 60s. There is also some model spread showing up on the northward progress of the warm front resulting in a range of high temperatures from the upper 30s northern Thumb to lower 60s Ohio border for Wednesday afternoon.

There is a pause in precipitation Wednesday night and Thursday, in between the departing Wednesday system and the next larger scale wave that breaks away from the Pacific Coast long wave trough. This system moves inland and into the central Plains Thursday on a track into the western Great Lakes Thursday night and Friday where it merges with the leftover frontal zone from the Wednesday system. Longer range model runs indicate an occlusion over Lower Mi that favors rain at onset changing to a rain/snow mix as the system pivots through the area Friday and exits Friday night. Temperatures then drop back toward normal mid/late February readings for next weekend.

MARINE...

A weak cold front settles across the Great Lakes today, with wind ahead of it organizing out of the south to southwest at 10 to 15 kt. The front passes over Lake Huron this afternoon and evening with a chance of rain, then wind shifts to northwest and subsides tonight as a ridge of high pressure builds in. This high maintains benign conditions through Tuesday before an area of low pressure tracks from the Midwest into the region Tuesday night into Wednesday. Easterly wind will become gusty across Lake Huron, with ensemble probabilities favoring a window from daybreak Wednesday to early afternoon for gusts to 35 kt gales. Elsewhere, gusts to 25 to 30 kt will be possible. This system will also bring widespread precip with rain in the south, snow in the north, and wintry mix in between. A second low pressure system is likely to track into the Great Lakes from the Midwest on Friday with another round of widespread precipitation and gusty easterly wind.

HYDROLOGY...

A large low pressure system brings a reinforcing surge of warm air and widespread rain to the region Tuesday night and Wednesday. Rainfall totals are projected to range from 0.25" to locally 1" during the time from Tuesday evening to about noon Wednesday. The highest amounts are forecast across the Saginaw Valley and Thumb regions, closest to the track of the surface low. The rain will occur on top of a melting snowpack that has a Snow Water Equivalent analysis ranging between 0.5" to 1". The combination of rain and snow melt on frozen ground may lead to rises on area streams and rivers. Ponding of water on roads is also possible, especially where drains could be blocked by snow and/or winter debris.

DTX WATCHES/WARNINGS/ADVISORIES

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