Marine Weather and Tide Forecast for Port Huron, MI

AVIATION

A low pressure system approaching the north shore of Lake Superior is producing a broad SW wind field from the Midwest into the Great Lakes which draws warmer air into Lower Mi today. Low clouds initially range borderline MVFR/VFR in a combination of lingering Lake Michigan activation feeding into the surface front across Lake Huron and southern Ontario. MVFR becomes more confined to the area north of FNT during the morning and especially at mbS should light snow also contribute a visibility restriction while grazing the area until mid afternoon. Farther south toward DTW, VFR below 5000 ft clears to the north and east during the morning leaving just mid and high clouds in a strengthening warm sector for the afternoon that develops northward and holds through tonight. SW wind gusting near 30 knots becomes the aviation weather focus this afternoon and well into this evening as the steep surface pressure gradient favors gusts holding for a few hours after sunset.

DTW THRESHOLD PROBABILITIES...

* High for cig aob 5000 ft this morning. Low this afternoon and tonight.

PREV DISCUSSION
Issued at 346 AM EST Sat Dec 7 2024

DISCUSSION...

There will be a chance of snow through the early part of the day for those in Mid MI and the northern Thumb drier and warmer air begins moving into the region later this afternoon and evening. Overall there are not many surprises with the latest round of model guidance. The one notable change is the more aggressive push of drier air this afternoon and evening which should bring an end to the snow earlier. The forcing for the light snow will be the lead flanking isentropic arm of clipper that will track across southern Ontario today. Dry resident airmass will eat up a bit of the moisture as it tries to saturate from the top down. All the while the best upper level support will be well to the north with the warm front also getting pulled north through the early part of the day.
Also hurting snowfall totals will be the warm air advection with the bulk of the saturation occuring in the 0C to -10C layer, with poor saturation in the elevated DGZ. Low QPF less than a tenth of an inch will result in light snowfall maybe up to an inch for the northern Thumb with snow tapering off down to I69. Other issue today will be the wind again. There will be a 50 knot low level jet sliding through lower MI reaching down to around 900mb. Even with shallow mixing depths today, soundings and probabilistic guidance shows continued support for wind gusts up to around 30 mph this afternoon.

Warm air advection and shortwave ridging in a pseudo slit flow pattern will be short lived but will offer a couple above average days as highs increase into the 40s Sunday and upper 40s Monday. The pattern will offer a period of light rain as well Sunday night into Monday as the northern periphery a southern stream shortwave lifts into the region. The compact and strong wave will track through the Ohio Valley early Monday the northern part of the precip shield and a theta e surge lifting into southern MI. Overall it looks like the bulk of the moisture will be below 700 mb as it occurs beneath a upper level ridge sliding over at the same time. Rain will move in early Monday morning and will last into the evening before tapering off. Not much support for more than 0.25 inches of rain out of this system with local probabilistic guidance showing less than a 40% chance for anyone to exceed that amount.

Quick flip back to the cold side as the next northern stream trough digs into the Great Lakes by Wednesday. A cold front early in the day will usher cold air to the tune of -10C Wednesday morning, mid negative teens overnight and possible -20C by Thursday. This will drop highs back down to the 30s Wednesday and 20s on Thursday. It will also open the door for lake effect snow showers to impact the state once again.

MARINE...

A weak ridge of high pressure will slide across the Great Lakes this morning causing westerly winds to weaken to between 10 and 20 knots early today. A strong clipper system dropping into the northern Great Lakes will then cause winds to back to southwesterly and increase through the afternoon and evening. Gusts are forecast to reach gale force across Saginaw Bay and central/southern Lake Huron through this evening and a Gale Warning remains in effect. Small Craft Advisories have been issued across the nearshore waters for gusts of around 30 knots. This system will also bring an area of widespread snow today, mainly across Lake Huron.

Winds will begin to subside after midnight as the system departs east. A trailing cold front will ease across Lake Huron on Sunday but stall there as westerly wind continues to weaken through the day. This boundary will act as the warm front for the next system set to track in from the Midwest on Monday. Winds veering from southeast to southwest with this system look to remain below headline criteria at this time.

DTX WATCHES/WARNINGS/ADVISORIES

MI...None.

Lake Huron...Gale Warning from 4 PM this afternoon to midnight EST tonight for LHZ363-421-422-441-462>464.

Small Craft Advisory from 4 PM this afternoon to midnight EST tonight for LHZ442-443.

Lake St Clair...Small Craft Advisory from 4 PM this afternoon to 4 AM EST Sunday for LCZ460.

Michigan waters of Lake Erie...Small Craft Advisory from 4 PM this afternoon to 4 AM EST Sunday for LEZ444.

Low Water Advisory from 4 PM this afternoon to 10 AM EST Sunday for LEZ444.