Marine Weather and Tide Forecast for Caseville, MI

DISCUSSION

An axis of rain is extending across nrn Illinois into cntl Lower Mi along a region of enhanced mid level frontogenesis. Ample moisture transport along a 50 knot low level jet is resulting in excellent theta e convergence along the elevated portion of the front. This will translate across Se Mi during the 09Z to 15Z time frame as the stronger low level inflow translates across Se Mi. Elevated instability is forecast to be fairly weak during the morning, limiting the thunder potential. Rainfall amounts will be a little higher across the Saginaw Valley and thumb regions (half to one inch) where the mid level FGEN will be more persistent. Veering of the low level inflow and a progressive mid level short wave will result in a brief duration of the stronger FGEN forcing across the south, likely keeping rain totals under a half inch. The associated surface low rippling along the front is forecast to track along or just south of the I-94 corridor this morning. Warm moist air in the warm sector will hold temps in the 50s, while locations to the north see temps largely in the 40s under weak post frontal cold air advection. Several hi res solutions indicate additional scattered shower development across the Saginaw Valley/thumb region late this afternoon/evening as a secondary short wave moves across cntl Lower Mi.

Mid level confluence will then expand across the region tonight into Saturday allowing surface high pressure and dry air to dominate. The degree of dry air and anticyclonic flow will result in a clearing trend tonight and allow a good deal of sun during the first half of the day Saturday. Ensemble guidance supports highs in the 50s Saturday, with cooler readings along the lakes.

Expansion of the long wave ridge toward the eastern seaboard during the latter half of the weekend will establish deep layer southwest flow across the Great Lakes, leading to a significant warming trend.
The initial influx of warm moist air Saturday night into Sunday will provide the next chance for showers. The passage of the associated surface warm front will drive the warm sector into Se Mi Sunday.
Ensemble members strongly suggest Sunday highs well into the 70s, with the possible exception of the thumb region. Warm sector mixing will also lead to a windy day Sunday. A few ECMWF ensemble members indicate peak wind gusts over 40 MPH. This will all be dependent upon how quickly the warm sector expands into Se Mi. Seasonally warm and moist air is forecast to prevail through much of next week.
While this is still a bit far out in the forecast, the projected instability parameters combined with the strong wind fields raise concerns for episodes of severe weather next week.

MARINE

Additional opportunities for showers this morning, including a few rumbles of thunder further south, while some light snowfall is possible for the north/central Huron basin. The responsible upper level wave moves across the northern Great Lakes throughout the day with rather weak northwesterly gradient winds (prevailing below 15 knots). High pressure then builds in from the west to start the weekend with drier and weaker flow flipping south-southeasterly.
Active weather will be possible again Sunday through Wednesday due to several passing disturbances. Potential exists for gusts to gales, mainly late Sunday into Monday, for portions of Lake Huron.

HYDROLOGY

Widespread rain will affect the area this morning. The more persistent rain will occur across the Saginaw, Tittabawassee and Cass River basins. There is high probabilities for a half inch to three quarters of an inch in this area, with low probabilities to exceed an inch. These amounts are not expected to result in notable rises on area rivers. The metro Detroit and Ann Arbor regions will see a shorter duration of rain, with lower probabilities for amounts to exceed a half inch.

PREV DISCUSSION
Issued at 1146 PM EDT Thu Apr 9 2026

AVIATION...

A tightening gradient of geopotential heights in combination with a marine release off of Lake Huron will lead to a strengthening baroclinic zone and easterly wind over the forecast area. Strong low level jet and 850mb frontogenesis leads to widespread rain from north to south through 15z. Rainfall rates are expected to be good enough for IFR conditions/ceilings. Low confidence exists in Thunderstorms and will amend as needed. Wave of low pressure should result in a fairly abrupt end to rainfall Friday morning with organized subsidence ending precipitation. MVFR stratus is expected for much of the day Friday.

For DTW...TEMPO for rain showers between 03-06z with prevailing IFR rain 11-15z Friday.

DTW THRESHOLD PROBABILITIES...

* Medium for ceilings at or below 5000 ft tonight. High Friday.

* Low for thunderstorms this evening. Low for thunderstorms Friday.



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