textproduct: Detroit/Pontiac

KEY MESSAGES

- A Cold Weather Advisory is in effect this morning for the first episode of dangerous cold wind chills.

- Snow showers today are expected to produce a dusting to less than an inch of accumulation, with a low chance for isolated snow squalls.

- Windchills Thursday morning are expected to be in the 10 to 15 degree below zero range and windchills Friday morning are expected to be in the 15 to 20 degree below zero range.

AVIATION

Wave of light snow has crossed into the southern terminals this morning leading to a minor VFR decrease in visibilities. Ceilings have lowered to MVFR at all terminals, and should mainly hold at this classification for the bulk of the daylight hours. Snow shower character transitions to lake effect by the midday hours as low- level winds veer northwesterly with the passing Great Lakes system. This affords slightly higher potential to reach IFR visibilities during any briefly higher snowfall rates. Southwest winds veer WNW with time, gusting to around 25 knots. Snowfall tapers off around nightfall with scattering ceilings and weaker winds settling westerly for the overnight hours.

For DTW...Light snow at times today, mainly VFR visibilities with MVFR ceilings. Additional light lake effect possible Wednesday.

DTW THRESHOLD PROBABILITIES...

* High for ceiling at or below 5000 until 00Z.

* High in precipitation type as snow.

PREV DISCUSSION

Issued at 333 AM EST Tue Jan 27 2026

DISCUSSION...

Steady drop in temperatures during the late evening with a southwesterly gradient wind of 20 to 30 mph was sufficient to cause windchills of 15 to 20 below zero across Southeast Michigan. The coldest windchills have occurred over the southern forecast area, south of the I 69 corridor as cloud was able to temper the surface temperature drop across the north. While windchills will likely rise heading into sunrise, will keep the Cold Weather Advisory in effect.

Upper level low pressure circulation digging into Lake Superior is sending a wave of 750-600mb warm advection through Southeast Michigan during the pre-dawn hours. Upstream radar mosaic and surface observations earlier supported widespread visibility restrictions in falling snow of 1/4-2SM. Heaviest activity has occurred in closer proximity to the radar sites (lower elevation sampling) with an obvious Lake Michigan moisture enhancement contribution. Z values have weakened as the warm advection wave pushes through Southeast Michigan and snowfall rates will be less. Forecast soundings support fairly high static stability from the surface up to 12.0 kft agl this morning. Nonetheless, will continue numerous/likely wording for light snow with accumulations this morning with just a couple of tenths of accumulation with low liquid equivalent. Significant cold advection in the 2.0 to 6.0 kft agl layer is forecasted to occur during the late morning and early afternoon hours. Steep, conditionally unstable lapse rates are highlighted in the forecast soundings so snow showers or isolated snow squalls will be possible. Latest hires time lagged ensemble supports surface winds in the post cold front environment early this afternoon of 25 to 35 mph. Still some question on the coverage of snow shower banding and how far eastward any snow bands will progress or extend. Preference was again to go with a high PoP/low QPF this afternoon. The grids will have total snowfall amounts today of around 1/2 inch. Locally higher amounts will be possible particularly north of the I 69 corridor dependent on duration of banding this afternoon.

The arctic pattern is forecasted to persist throughout the remainder of the work week and at least into the first half of the upcoming weekend. Not a lot of moisture advection is forecasted during the coming days, but given the thermal profile will likely see chances for perpetual flurries or at times light snow showers. The big forecast question will be the need for additional Cold weather and windchill headlines this week. For Tonight/Wednesday morning, the cold air intrusion is shown to undergo a quick moderation with 850mb temperatures warming a few degrees to -18-19C. Do think clearing will take place tonight so the question comes down to surface winds. Data suggests a surface wind of around 5 mph late tonight and latest 5.0 NBM places 50th percentile for Apparent Temperatures at around -8 to -10F tomorrow morning. Will not be issuing a Cold Weather Advisory for Wednesday morning this forecast package. The next arctic intrusion will reinforce the eastern NOAM trough and bring 850mb temperatures down to -22C for Thursday and Friday. The current forecast has low temperatures Thursday morning between 0 to 5 below, with readings Friday morning of between 7 to 10 below. Windchills are expected to bet 12 to 15 below zero Thursday morning and 15 to 20 degrees below zero Friday morning. Cold Weather Advisories will likely be needed at some point during the late week.

Some filling of the trough with rising geopotential thickness supports not as extreme temperatures this weekend. Still cold, however, with below normal temperatures windchills Sat/Sun night ranging 5 below zero to 5 above zero. No significant moisture advection or precipitation event anticipated.

MARINE...

Another arctic front will track through the Central Great Lakes today. Southwest winds ahead of the front early this morning, with gusts around 30 knots expected. A few brief gusts to marginal gales over the open waters of Central Lake Huron are also in play. Snow showers will accompany the front, transitioning to localized lake effect activity this evening and tonight over Lake Huron with northwest winds leading to a Lake Superior-norther Lake Huron connection. Low level winds back to the west by Wednesday morning and look to be around 20 knots or less through the day, as yet another arctic front and cold airmass arrives. Very cold airmass (negative mid 20s at 850 MB) will lead to lake induced trough on Thursday, with northerly winds kicking in to finish the work week. Wind speeds look to remain under 30 knots.

DTX WATCHES/WARNINGS/ADVISORIES

MI...Cold Weather Advisory until 10 AM EST this morning for MIZ048-049- 053>055-060>063-068>070-075-076-082-083.

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