Marine Weather and Tide Forecast for Estral Beach, MI

DISCUSSION

The cutoff upper low responsible for the early morning MCS continues to meander over the upper Midwest today. Sunny conditions are expected through the daylight hours as mid-level subsidence dominates in the wake of the morning convection. Deep southwesterly flow brings in a secondary warm sector with highs reaching the mid 80s. Strong daytime mixing will cause dew points to fall to the lower to mid 50s - offering a less humid feel compared to yesterday.
Southerly wind becomes breezy to around 20 to 25 mph, eventually advecting in dew points back into the mid to upper 50s by the evening. Meanwhile, mid-level cooling commences late in the day as the upper trough begins to pivot into the central Great Lakes, allowing instability to build as 700-500mb lapse rates increase to around 8 C/km. Forcing is disorganized through the early evening hours suggesting little potential to overcome the resident cap near 700mb.

After 00z, upper flow becomes increasingly unbalanced at the nose of a 90 kt jet streak as the trough takes on a negative tilt - providing better support for synoptic lift and convective initiation as a pre-frontal surface trough lifts northeast across the area.
Given the timing near and after sunset, there remains uncertainty regarding whether the cap will erode and instability (~750 to 1000 J/kg MLCAPE) will become realized at the surface before storms move through. Bulk 0-6km wind shear of 40 to 50 kt is supportive of a broken line of strong to severe storms with damaging wind and large hail the main threats. Severe potential is highest between 8pm and 1am before the trough sweeps through, then lingering showers and sub- severe storms may persist into the morning hours as the cold front trails behind. Most areas will receive around or less than 0.25" of rain tonight, but localized areas may see up to around 1".

The stacked low pressure system slowly advances into northern Lake Huron on Saturday with a much cooler air mass working in through the day. Highs reach the 60s as a tight pressure gradient produces gusty westerly winds to 30 to 40 mph. Moisture wrapping around the low and weak instability will bring a continued chance for light showers at times through the day. Mid-level ridging then begins to settle into the area Sunday into the early work week to favor surface high pressure with dry and cool conditions. The next period to watch will be Tuesday night into Thursday as a closed low tracks from the Midwest toward the Great Lakes and Ohio Valley. This will provide the next opportunity for showers and storms.

MARINE

Southerly 15-20kt winds develop today following the passage of last night's warm front as the surface low tracks over Lake Superior.
Stubborn areas of fog likely linger through at least the morning though with dewpoints falling, expectation is the decreasing humidity should allow for a gradual diminishing trend for the latter half of the day. Respectable cold front is set to sweep across the region late tonight supporting another round of showers and thunderstorms in advance. Set up is not as favorable compared to Thursday night with coverage likely limited to a broken line with any strong to severe embedded storms being more isolated in nature.
Moderate west-southwest winds follow Saturday with the strongest winds (20-30kts) expected over the southern half of the region where the gradient is strongest. Small craft advisories are warranted for most if not all nearshore waters as a result. Low fully departs Sunday shifting winds to the northwest. Gusts peak near 20kts during the day before weakening overnight as weak high pressure slides overhead.

PREV DISCUSSION
Issued at 1232 AM EDT Fri May 16 2025

AVIATION...

Squall line producing very strong winds, large hail, isolated tornados, and persist downpours continues to work from west to east across the terminals tonight. Gusts in excess of 60 knots and at least one confirmed tornado have been reported upstream with this system. Trends continue to favor MVFR visibility reductions in the main rain band, with brief IFR reductions noted at mbS and FNT.
Timing the exit is the main forecast concern for the next TAF cycle as the lingering back-edge will be slower to depart from DTW and DET near the very beginning of the TAF window. The line should fully clear east of all sites by 07Z. Post-frontal VFR conditions move in early Friday and throughout the day. Surface flow weakens, backing from southwest to southeast during the afternoon. Additional showers and storms possible late Friday evening.

For DTW/D21 Convection... A decaying line of strong to severe thunderstorms crosses DTW during the 05-06Z time window.

THRESHOLD PROBABILITIES...

* Medium for ceiling 5000 feet or less toward midnight through sunrise the low through Friday.

* High for thunderstorms tonight, mainly 05-06Z Friday, then low confidence after 00Z Saturday.



DTX WATCHES/WARNINGS/ADVISORIES
MI...None.
Lake Huron...None.
Lake St Clair...None.
Michigan waters of Lake Erie...None.