Marine Weather and Tide Forecast for Pinconning, MI

AVIATION

Surface ridging briefly backs winds to the west-southwest this morning ahead of a weak cold front that is just now entering northern Lower Michigan. This front will be the focus for shower activity beginning late this morning and expanding in coverage throughout the afternoon. Very steep low level lapse rates extend up through 10.0-15.0 kft agl leading to weak instability this afternoon. A rumble of thunder cannot be ruled out as a result, while a more likely outcome is graupel and/or wet snowflakes mixing in with rain. Well-mixed profiles will also support gusts to 25 knots, peaking this afternoon as the cold front tracks through. Post-frontal airmass will be drier affording a clearing trend again overnight as high pressure returns to the airspace.

DTW THRESHOLD PROBABILITIES

* Low for ceilings at or below 5000 feet now through late morning.
Medium late this morning through the evening.

* Very low for a rumble of thunder this afternoon between 17z and 23z.

PREV DISCUSSION
Issued at 305 AM EDT Sun Apr 19 2026

DISCUSSION...

Satellite trends this morning show a definitive back edge to the clouds with clearing working into the forecast area. Morning sunshine will give way to afternoon clouds. Not making any changes to the temperature forecast but temperatures today may be a touch mild, conditional to the radiational cooling that occurs ahead of sunrise.

Composite H3-H5 trough axis and associated absolute vorticity maximum will track directly over Southeast Michigan this afternoon.
Plan views of 300mb winds depict an additional northern stream jetlet merger into the broader left entrance region over the eastern contiguous US resulting in ageostrophy and increased 850mb frontogenesis over Southeast Michigan between 17-23z. Cooling aloft provided by the shortwave in combination with minor low level thetae advection is expected to result in steep lapse rates from the LCL at 6.0 kft agl upwards to 17.0 kft agl. Given the dynamics and the relatively high convective depths, feeling is that coverage of shower activity will be fairly high. Therefore, intermittent cellular showers are anticipated this afternoon and increased PoPs to greater than 60 percent for most of the area. Saturation through the DGZ does bring the potential for some melting snowflakes particularly north of Metro Detroit, but the more likely scenario for mixed phase precipitation is brief graupel/snow pellets. Cloud ice supports a potential for lightning see SPC SWODY1. Inverted V supports gusty wind potential with the showers, perhaps 30 to 40 mph possible.

Stout cold air advection with polar air mass brings high confidence and high certainty that surface temperatures will drop into the middle to upper 20s after midnight tonight. NBM provides an interquartile range on temperatures late tonight of between 23 to 30 degrees. With collaboration considerations, upgraded to a Freeze Warning from 11 pm this evening until 11 am Monday morning.

Strong 1000-500mb geopotential height rises and confluence aloft will support high pressure on Monday with ridging persisting into the daytime on Tuesday. Cool, below normal temperatures (40s) are expected Monday before moderating significantly Tuesday afternoon (60s). Warm advection in combination with exit region dynamics may provide enough ascent for some scattered shower activity particularly over the southern forecast area Tuesday evening/night.
The current forecast has slight chance PoPs south of Detroit.

High amplitude ridge is forecasted to build into much of eastern North America for the end of the week. A notable warming trend with upper 70s temperatures and dewpoints in the 50s possible.

Not the highest of confidence in the deterministic solution space for next weekend as recent model runs are suggesting more progressive weather across the Great Lakes. Huge sensible weather variance exists across the region as timing and southward extent to occlusion of central United States low pressure system will matter. For now, the cold front is forecasted to push into Southeast Michigan Friday night and Saturday morning per ECMWF and GFS.

MARINE...

A persistent pressure gradient maintains breezy westerly wind through the morning. A cold front tracks across the area this afternoon, bringing a chance for rain/snow showers and potential for a rumble of thunder. Small Craft Advisories remain in effect during the day for Lake St. Clair and western Lake Erie where the westerly flow ahead of the front will become gusty to around 25 kt. Behind the front, wind shifts northwest and gradually increases to the 20 to 30 kt range across Lake Huron tonight. Additional Small Craft Advisories go into effect this evening for the Lake Huron nearshore waters as wave heights build over 4 feet. High pressure builds directly into the Great Lakes on Monday allowing winds and waves to subside. Gusty south wind then develops Monday night into Tuesday ahead of the next cold front tracking across the upper Midwest.

DTX WATCHES/WARNINGS/ADVISORIES
MI...Frost Advisory until 10 AM EDT this morning for MIZ053-060>063- 068>070-075-076-082-083.

Freeze Warning from 11 PM this evening to 11 AM EDT Monday for MIZ053-060>063-068>070-075-076-082-083.

Lake Huron...Small Craft Advisory from 8 PM this evening to 10 AM EDT Monday for LHZ421-441>443.

Lake St Clair...Small Craft Advisory from 10 AM this morning to 8 PM EDT this evening for LCZ460.

Michigan waters of Lake Erie...Small Craft Advisory from 10 AM this morning to 8 PM EDT this evening for LEZ444.