Marine Weather and Tide Forecast for Flint, MI

AVIATION

A cold front will progress across the terminals early this morning bringing widespread MVFR ceilings with pockets of IFR ceilings and scattered light snowfall that may reduce visibility to MVFR and IFR conditions. Total snow accumulations are expected to be well less than an inch. Greater snow potential and greater VSBY/CIG reductions are expected across FNT and mbS with lesser VSBY/CIG reductions across the southern metro terminals. Snow showers come to an end before 12Z as post frontal winds out of the west pick up around 11-12Z with gusts to around 20 knots. Cold airmass will result in a return to lake effect regime off Lake Michigan this afternoon with low clouds persisting through the afternoon. Aside of any scattered lake effect flurry activity, a passing system to the south brings low chance for VFR light snowfall during the afternoon for the metro terminals. Will highlight with a PROB30 group. Dry air will try to scatter out some clouds after 00Z this evening.

For DTW...Best chance for snow showers will be between 07Z and 11Z.
Weak forcing should result in mainly a dusting of accumulation overnight.

DTW THRESHOLD PROBABILITIES...

* High in ceilings below 5000 feet through this morning and afternoon.

PREV DISCUSSION
Issued at 330 PM EST Fri Dec 12 2025

DISCUSSION...

For the remainder of the afternoon and evening... A stratus deck has filled back in across SE MI which will sustain into the overnight hours under an established low-level inversion. Overnight, a strong PV anomaly now extending into northern Minnesota will continue to drive south into the northern Great Lakes. This will push a cold front over Michigan through the morning hours and will bring the chance for light accumulating snow. Both the shallow moist isentropic ascent up through 750mb ahead of the front and shallow convergence along the cold front itself will provide forcing for light snow chances overnight. Snowfall totals will range from trace amounts, up to a half-inch, with snow chances ending by 12Z.

Strong cold air advection behind the front will bring decreasing temperatures through the day and will maintain a shallow but stark mixing layer which will produce wind gusts on the order of 20 to 30 mph. Cold temperatures in conjunction with breezy conditions will produce wind chills around 0 degrees to the low single digits across SE MI by the afternoon hours. Flurries will remain possible given the shallow but strong lllr and sufficient 0-1km moisture, but moisture depths are too shallow to sustain accumulation. The one exception will be around I-94 and locations south in the afternoon and early evening as an upper-level wave rounds into the Ohio Valley. The northern precipitation shield of this feature has low- end chances to clip southern Michigan which can bring light accumulations up to a half-inch. The updated forecast will hold Pop values to 20% up around the I-94, increasing to 50% near the border.

The upper-level wave will continue to deepen across the Great Lakes through the weekend which will reinforce this significant cold air intrusion. While the magnitude of the wind speeds are not out of the normal, ensemble v-wind anomalies highlight the rarity of a sustained due-northerly fetch for mid-December, maximizing cold air transport. 850mb temperatures drop to near -20C and 700 mb temperatures to -26C by Sunday morning. Temperatures drop to around the 0 degree mark Sunday morning with wind chills ranging from -15F to -10F. A cold weather advisory will be under consideration for parts or all of the cwa for Sunday morning. Temperatures remain capped in the 20s for a high on Sunday, returning into the single digits overnight, with a return back into the 20s by Monday.
Overall, expect temperatures to run roughly 20 to 25 degrees below normal through Monday.

A Pacific wave will arrive onshore by the midweek which will deepen east of the Rockies before arriving across Michigan Thursday. Flow will back to the southwest in response to this wave, bringing temperatures back to near normal values Tuesday and likely above normal Wednesday-Thursday, with Thursday having the best chance to see temperatures peak aoa 40 degrees. While near the end of the forecast package, ensembles are showing moderate convergence highlighting moderate ivt ahead of a cold front on Thursday, bringing increasing confidence for rain showers.

MARINE...

Southwesterly winds will be slowly increasing through the rest of the day and overnight ahead of an approaching arctic front tied to a low pressure system that will track across Ontario tonight. Winds will turn westerly overnight behind the front and will increase with gusts up to 30 knots possible across parts of central and southern Lake Huron. Winds will remain elevated in the upper 20 knot range through Saturday with the coldest of the arctic air arriving late Saturday and overnight which will cause a boost to the winds to around 30 knots across the southern basin. At this time, guidance suggests we'll stay below 35 knot gales but that will be something to watch in the coming days. A long duration Small Craft Advisory is in effect this evening through Monday morning to account for this cold unstable airmass and period of wind and waves. The cold airmass and elevated winds will also lead to potential snow squalls and freezing spray as well.

DTX WATCHES/WARNINGS/ADVISORIES
MI...None.
Lake Huron...Small Craft Advisory until 4 AM EST Monday for LHZ421-441.

Small Craft Advisory until 4 PM EST this afternoon for LHZ422.

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