Marine Weather and Tide Forecast for Gibraltar, MI

DISCUSSION

Thermal trough takes brief residence today with temperatures currently in the 20s forecast to rebound into the 30s and lower 40s this afternoon. A dry column will support a good amount of sunshine today, though lake moisture advecting through within cyclonic flow supports a diurnal flare-up of high-based cumulus. Steep lapse rates and deep mixing result in a 20 to 25 mph breeze which holds wind chills in the 20s and 30s.

An energetic 170 kt upper jet working into the PNW this morning will drive the next period of active weather late tonight into Friday. A compact and vigorous shortwave at the nose of this jet and subsequent ageostrophic response will produce a powerful clipper that tracks across northern MI during the day Friday. Sharp exit region ascent precedes the system in a brief burst of snow expected to occur over a ~4-6 hr period mainly between 2am and 10am. Surface wet bulb temps at onset will be in the mid to upper 20s, then rise to the mid 30s through the morning as higher temps and dew points arrive from the southwest. This allows for accumulating snowfall overnight which transitions to melting snow later in the morning.
SLRs near 12:1 result from the impressive lift, which is forecast to produce 1-3 inch accumulation north of M-59. Highest confidence in 3 inch amounts, with about 20-30% chance to see 4 inches, exists in northern Bay/Midland/Huron Counties and considered these areas for a Winter Weather Advisory, but decided to let the next shift assess morning model data for higher confidence. South of M-59, 0 accumulation to a wet 1 inch is expected before melting ensues.
Additional rain/snow showers are possible the rest of the day but with accumulation unlikely.

11.12z NAEFS/ECMWF ensemble MSLP mean deepens the low to ~988mb as it tracks across Lake Michigan Friday morning. This is near the 0.5th percentile for this time of year, and will note that 12.00z deterministic runs generally depict a slightly stronger system. The resulting gradient will bring strong wind through the day Friday.
Initially from the south as the 50-65kt LLJ passes overhead during the morning, wind will veer around to west as the low reaches Lake Huron in the afternoon. There is still an appreciable amount of model spread wrt wind magnitude at the surface, driven by placement of the LLJ core, variable stability in the warm sector during the morning, and depth of moisture/stratus that works through during the afternoon which will affect mixing heights and lapse rates. Do have enough confidence at this stage to issue a High Wind Watch for all of the area, with current guidance supportive of a high end Advisory but with room for headline adjustment in later forecast packages as needed. The going forecast will call for wind gusts of 50 to 55 mph with a morning peak associated with the passing LLJ, and then a secondary peak during deepest mixing in the afternoon. Highest confidence in the higher gusts will be south of I-94 where the gradient is maximized and low-level moisture may be less of a limiting factor.

The next 170 kt upper jet streak arrives over the PNW late Saturday, this one digging more meridionally and driving a trough down to the Gulf Coast late this weekend. This highly dynamic wave kicks off deep cyclogenesis over the corn belt which spreads a band of elevated warm frontal snow across the Great Lakes Saturday night into early Sunday. Several inches of accumulation will be likely before the elevated forcing lifts north, possibly with a brief transition to wintry mix as a warm nose arrives midday. The latest NBM advertises 50-100% probability for 2+" for areas north of I-94 by 00z Mon. Also of note is 60% probability for 6+" in the Saginaw Valley, which will be positioned tenuously close to the system's heavy deformation axis based on current guidance. Confidence is increasing for the surface low center to track across Lower MI Sunday night, suggesting brief residence time within the warm sector and potential for thunderstorms overnight. Gusty winds and snow showers ensue Monday into Tuesday as much colder air is dragged in.

MARINE

Northwest flow continues in the wake of a cold front. The favorable fetch across north and central Lake Huron along with elevated mixing depths from colder air aloft will allow for breezy conditions through the morning. Wind gusts around 30 knots will be likely, with isolated gust to gales through 10AM EDT. Winds decrease through the late morning and afternoon hours as a ridge of high pressure briefly fills in across the region.

Attention then quickly turns a clipper low pressure system that moves in across northern lower Michigan and northern Lake Huron tomorrow morning. A very strong pressure gradient will accompany this seasonably strong low pressure system which will result in a rapid uptick in sustained winds and gusts, along with winter weather. Given the strength of this system, gust to high-end gales and sustained winds to gales are expected. A Gale Warning has been issued for all marine areas. Additionally, there will be a window for storm force gusts through the day tomorrow, south of the low pressure system. There are still small deviations as to where storm force gusts will be possible pending this track of the low, but Lake Erie to Lake St. Clair will be locations will have potential for these stronger gusts, with additional lowered chances across the Saginaw Bay and southern Lake Huron.

This low pressure system exits the area tomorrow night but will pull in colder air in its wake, sustaining breezy conditions through early Saturday.

PREV DISCUSSION
Issued at 1145 PM EDT Wed Mar 11 2026

AVIATION...

Low level dry air advection is making good progress across western Lower Mi, marked a rapidly advancing clearing line. This clearing will make its way across the terminals during the first hour or two after TAF issuance. The clear skies will offer some degree of decoupling in the boundary layer, leading to some degrease in wind speeds/gusts into the early morning hours. Deepening daytime mixed layer will lead to a slight uptick in winds Thursday afternoon. Dry low level air will limit afternoon clouds to just some higher based cu.

DTW THRESHOLD PROBABILITIES...

* High for ceilings at or below 5000 feet very early in the forecast period.



DTX WATCHES/WARNINGS/ADVISORIES
MI...High Wind Watch from late tonight through Friday evening for MIZ047>049-053>055-060>063-068>070-075-076-082-083.

Lake Huron...Gale Warning from 4 AM Friday to 4 AM EDT Saturday for LHZ361>363- 421-422-441>443-462>464.

Small Craft Advisory until 4 PM EDT this afternoon for LHZ421- 441>443.

Lake St Clair...Gale Warning from 4 AM Friday to 4 AM EDT Saturday for LCZ460.

Michigan waters of Lake Erie...Gale Warning from 4 AM Friday to 4 AM EDT Saturday for LEZ444.