textproduct: Detroit/Pontiac

KEY MESSAGES

- Areas of freezing fog can be locally dense through the morning mainly north of I-69.

- Above normal temperatures resume this afternoon and continue through mid week.

- The next precipitation event is on schedule for Tuesday night and Wednesday. It is an all rain event with wintry mix nearby to the north of the Tri Cities and northern Thumb.

AVIATION

A broad cirrus shield presently in place across roughly Port Huron to Coldwater will continue to progress southeast through the morning hours. The development and expansion of freezing fog north of the cirrus shield has ramped up over through the mid-morning hours with highly variable coverage and density, ranging from IFR to MVFR visibility restrictions. Decreasing visibility trends down to LIFR remain possible and would be most likely across KMBS and KFNT as this is where better radiational cooling resides outside of the cirrus. As the cirrus shield progresses out of Southeast Michigan, some lowered visibility trends will be possible for locations south just prior to sunrise. After sunrise, lingering freezing fog will dissipate, leading to vfr conditions for the remainder of the day.

DTW THRESHOLD PROBABILITIES...

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

PREV DISCUSSION

Issued at 343 AM EST Sun Feb 15 2026

DISCUSSION...

Light and variable to calm wind and clear sky present a favorable fog/freezing fog setup mainly north of M-46 leading up to sunrise, and along and north of I-69 as cirrus peels away early in the morning. Locally dense visibility restriction is most likely in the Tri Cities and northern Thumb based on upstream observations and persistence of clear sky and calm wind to wring out full radiational cooling. Visibility trends will be monitored for later updates.

For the rest of today we have a diffuse surface pressure pattern across Lower Mi in between larger scale systems in the SE States and central Canada. After the fog, prospects for clouds are tied to a 500 mb short wave within the larger scale zonal flow that moves over Lower Mi this afternoon. It brings broken coverage of mid and high clouds again mainly north of I-69 along with limited coverage of stratocu within the weak surface pressure reflection late in the day and this evening. Still no precipitation indicated and the clouds are only a minor obstacle to another round of warm afternoon temperatures. Highs in the mid to upper 40s look good inland from the lakeshores with a few reports around 50 again toward metro Detroit and the Ohio border where full sun is more likely.

Surface high pressure builds in from the mid MS valley but with a less favorable fog setup tonight, limited by increasing high clouds and late developing south wind. The clouds thicken ahead of the next northern stream short wave which also nudges the surface ridge eastward before morning. The primary 500 mb wave is well north of Lake Superior however secondary Midwest low pressure produces a warm front capable of a larger cloud footprint across the Great Lakes during Monday. Mid level moisture transport also appears capable of spotty light rain grazing the Tri Cities and northern Thumb judging by model depictions of theta-e advection. Otherwise, the highlight for Monday is increasing SW wind that brings the next step in the warming trend leading to afternoon highs reaching the lower 50s.

The Monday system does have a trailing cold front which brings just a minimal air mass change as arctic air is contained across Canada. Wind veering SW to easterly combined with clouds nudge temperatures down a few degrees Tuesday but still well above normal for mid February. NBM guidance does a reasonable job reflecting the effect of wind direction with high temperatures limited to the mid 30s along the Lake Huron shoreline to upper 40s interior west of I-75.

The front stalls south of the Ohio border and quickly transitions to a warm front that becomes the focus for the beginning of the main precipitation event Tuesday night and Wednesday. Mid range deterministic solutions in the new 00Z model run are in good agreement on the current Pacific Coast closed low moving through the Rockies and into the Plains by Tuesday. This results in a broad area of strong surface cyclogenesis that has access to the moisture from Gulf modified air that is strongly transported northward along and north of the front Tuesday night. Generous QPF in widespread rain showers are the result across southern Lower Mi as the warm front moves northward but not entirely through the region until later Wednesday morning. There is enough cold air nearby to the north to monitor for potential wintry mix in the Tri Cities and northern Thumb where evening low temperatures are near freezing at precipitation onset then rise above after midnight.

Rain continues Wednesday morning until the mid level dry slot and low level warm sector of the system surge into the area by afternoon. Guidance high temperatures are trending upward compared to recent forecast cycles and are now in the lower 60s in the Detroit metro area compared to records the upper 60s for 18 Feb. Readings drop back into the 40s and 50s for Thursday as the track of the next low pressure system is also west of Lower Mi. The long wave trough axis also holds from central Canada through the Plains helping keep arctic air out of the Great Lakes through Friday.

MARINE...

A weakening trough settles into the Great Lakes today within a weak pressure pattern overall, ensuring light wind and waves for ice- free areas. Areas of marine fog will be possible through the morning with low predictability on location and longevity. South wind then increases to around 10 to 15 kt on Monday as a slightly stronger trough arrives. A ridge of high pressure maintains benign conditions through Tuesday before a more active pattern takes shape from Wednesday into next weekend. A frontal boundary will stall in the vicinity of the Great Lakes with multiple low pressure systems bringing rain, snow, wintry mix, and potential for gusty easterly winds during this period.

DTX WATCHES/WARNINGS/ADVISORIES

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