textproduct: Detroit/Pontiac

KEY MESSAGES

- Wind gusts of 45 to 55 MPH are forecast today; a few gusts to 60 MPH remain possible. A high wind warning remains in effect until 9 PM.

- Widespread snow showers will occur today, with some snow squalls possible. Snow and blowing snow will reduce visibilities.

- Cold air with the winds will hold wind chill readings in the single digits and teens today.

- Seasonally cold conditions will prevail through the end of the week.

AVIATION

Windy conditions in the wake of a cold front will remain prominent through the day as wind direction continues to veer from 240-260 degrees to 280 to 300 degrees. Sustained winds between 20 to 30 knots are expected with gusts ranging from 35 to 45 knots. An isolated gust up to 50 knots cannot be ruled out. The push of colder arctic air will also activate widespread lake effect snow with embedded heavy snow showers/snow squalls. The heavier snow showers are expected from the morning into the early afternoon and will be capable of producing LIFR visibility restrictions. MVFR ceiling develops some breaks late in the day and snow showers decrease in coverage and intensity towards the evening. Wind gusts intensity also to drop off late tonight but gusts to 30-35 knots remain possible overnight.

For DTW... Very windy conditions continue to ramp up through the morning and afternoon hours with gusts peaking around 45 knots. An isolated gust up towards 50 knots cannot be ruled out. Light snow expected through the day with some embedded snow squalls possible between 14Z-19Z. Squalls will be capable of producing a quick 1-2 inch of snow accumulation.

DTW THRESHOLD PROBABILITIES...

* High for ceiling below 5000 feet today.

* High for crosswind threshold exceedence through the evening.

* High for precipitation type as snow.

PREV DISCUSSION

Issued at 300 AM EST Mon Dec 29 2025

DISCUSSION...

Regional satellite loop shows a dual upper low; a weakening and shearing low over MO/IL and a rapidly deepening compact upper low racing across Nrn Lower Mi. The increasing mid level height falls associated with this upper low over the nrn Great Lakes is driving rapid deepening of the associated surface low, now located over nrn Lake Huron and projected to move into Georgian Bay by daybreak. The central pressure is expected to drop to around 978 mb by 12Z, roughly a 22 mb drop within 24 hours. This low, already occluded, will lift northeast into Quebec this afternoon as the compact mid level low remains fairly progressive.

The deepening and compact nature of this system is resulting in strengthening wind fields across the Great Lakes. Post cold frontal subsidence allowed brief gusts above 40 MPH last evening. More aggressive ongoing low level cold air advection concurrent with the increasing wind fields will increase the probabilities for gusts above 45 MPH this morning, with 45 to 50 knots expected within the deepening mixed layer. A sfc trough axis is forecast to move across Se Mi from northwest of southeast between 12Z and 18Z. There will be a veering of the winds from SW to WNW in the wake of this trough. Steepening of the low level lapse in the wake of this feature will sustain decent mixing and strong winds into the evening. There has been a bit of a downward trend in wind gusts potential with the 00Z model suite. Guidance is still supportive of a long duration of 45- 55 MPH wind gusts. This and to account for a potential for some slight overachievement on mixing will support maintaining the current high wind warning.

Deep layer wrap around moisture is forecast to pivot across Se Mi from roughly daybreak through early-mid afternoon within a region of weakening mid level deformation. The better larger scale ascent is forecast between 15Z and 18Z, warranting high snow probabilities during this time period. Increased boundary layer convergence along the aforementioned sfc trough and some Lake Mi enhancement will occur within a favorable thermo dynamic profile to produce some intervals of higher intensity snow showers. Based on the timing of the ascent, this will mainly be focused between 12Z and 18Z today. Convective snow probabilities are quite high for an inch or two of accumulation. There is a low chance for three inches from the northern Detroit suburbs up through the I-69 corridor and thumb. Given the winds, precise snowfall measurements may prove futile. The combination of gusty winds, sub freezing temperatures and brief heavy snow showers will likely pose some hazardous travel conditions. The transition to northwest flow this afternoon and evening will limit remnant lake effect into Se Mi.

Through the remainder of the week, an eastern Canadian upper low will sustain seasonally cold air across the Great Lakes. A progressive weak short wave/clipper will provide a high probability for light snow late Tues/Tues night, with limited accumulation (under two inches). A little stronger short wave forecast to pivot around the base of the upper low is forecast to deliver a reinforcing short of arctic air Wednesday into New Years.

MARINE...

A powerful low pressure is system passing over northern Lake Huron near peak intensity this morning. Strong SW to WSW wind will persist to its south this morning with strong gales expected and even some gusts to storm force possible. These strong winds will cause water levels to drop below low water datum at Saginaw Bay and western Lake Erie where Low Water Advisories are in effect. As the low departs east this morning, a surface trough will shift wind direction to NW and allow a surge of arctic air to spill across the area. Frequent strong gales continue through the afternoon and evening with gusts to storm force at times. Storm Warnings remain in effect for all of Lake Huron while Gale Warnings are in effect for Lake St. Clair and western Lake Erie. Snow squalls increase in coverage through the day, and heavy freezing spray will impact Lake Huron as well. Potential for storm force gusts dwindles this evening with gales likely to continue overnight into Tuesday morning before tapering off. A northwest flow pattern persists through much of the week, offering additional snow showers and occasional freezing spray. The next clipper arrives late Tuesday which brings an uptick in NW wind Wednesday but this looks to stay below gale force at this time.

DTX WATCHES/WARNINGS/ADVISORIES

MI...High Wind Warning until 9 PM EST this evening for MIZ047>049- 053>055-060>063-068>070-075-076-082-083.

Lake Huron...Storm Warning until 11 AM EST Tuesday for LHZ361>363-421-422- 441>443-462>464.

Heavy Freezing Spray Warning until 11 AM EST Tuesday for LHZ361>363.

Low Water Advisory until 4 PM EST this afternoon for LHZ422.

Lake St Clair...Gale Warning until 7 AM EST Tuesday for LCZ460.

Michigan waters of Lake Erie...Gale Warning until 7 AM EST Tuesday for LEZ444.

Low Water Advisory until 1 AM EST Tuesday for LEZ444.