Marine Weather and Tide Forecast for Auburn, MI

AVIATION

General trend is for low cloud (sub-5.0 kft) to linger through early Friday morning as cooler post-frontal flow has activated Lake Michigan and Lake Huron. There is a low chance for clouds to scatter this evening, but would be brief as winds veer to the NE and redirect downstream moisture overhead. High pressure slides across lower Michigan tonight, which lowers inversion heights and increases chances for MVFR conditions through 12z Friday. Winds eventually shift offshore Friday morning as diurnal heating ramps up to result in a clearing trend that persists through the rest of the TAF period.

For DTW/D21 Convection... Thunderstorms are not in the forecast through Friday.

THRESHOLD PROBABILITIES...

* High for ceiling 5000 ft or less today, moderate this evening, high between 04z and 12z Friday.

PREV DISCUSSION
Issued at 348 AM EDT Thu Jul 17 2025

DISCUSSION...

Morning surface observations reveal the progression of the approaching cold front which is now closing in on Lansing (as of 07Z). Muted upstream precipitation response, in the wake of the boundary, lends further confidence in lowering PoPs locally today as it translates across Southeast Michigan through the next 6 hours.
00Z global models have fallen in-line with prior CAMs in limiting QPF for the Southeast Michigan with the FROPA. Forecast soundings indicate column winds veering from SW to W which has led to steady drying, plus warming within the 800-700 mb layer leads to a capping inversion. This scenario pertains to most of the forecast area, but closer to the Tri-Cities and Thumb regions, instability lingers a bit longer. Paired with closer proximity to the surface low (and MCV), left some Chance PoPs until mid-morning, but residual activity should largely be thunderless. Post-frontal airmass supports some healthy coverage of stratocumulus through the diurnal cycle.
Becoming breezier with time as flow veers toward the northwest amidst sub-700 mb anticyclonic flow tracing back to northwest Ontario. This produces a surface thermal gradient of about 10F between highs over Metro Detroit (lower 80s) and the Tri-Cities (lower 70s). Seasonably cool overnight with lows dipping into the 50s, beyond Metro Detroit.

Surface high pressure passes over Lower Michigan Friday, on its way toward the eastern Great Lakes. Base of the thermal trough axis extends its gradient over the region, marked by a brief intrusion of 850 mb temperatures in the single digits (Celsius) during the morning hours. Lower column warming ensues as the day progresses, attributed to the shift toward a weak return flow pattern which transitions to light southerly gradient winds. Still subjectively pleasant for mid-July standards Friday with highs in the 70s and dewpoints in the 50s, perhaps lower 60s closer to the MI/OH border.

Dynamic zonal flow aloft, marked by 110+ knot jet streak at 250 mb, centers over the northern Great Lakes Saturday. Potential exists for periods of showers and storms Saturday with multiple features of note poised to impact the region. An MCS rolls across The Plains, clipping southern Lower as it anchors to a basal shortwave trough Friday night into Saturday. Meanwhile, a shall cyclonic circulation drifts east into northern Lower offering weaker precipitation intensity. MLCAPE values are expected to rise locally as the ThetaE plume gets shoved downstream, across Lake Michigan. Moisture advection will also be reinforced by a low-level shift to southwest flow. This lends a more favorable convective environment should glancing forcing materialize. Timing details still need to be worked out, especially as it relates to the southward redirection of height falls along the MCS. Becoming drier and cooler again Sunday as the longwave trough departs, but ridge amplification over north-central CONUS builds in early next week. Anticyclone over The Southeast builds into the Lower Mississippi Valley mid-week as +590 dam geopotential heights extend into southern Lower. Ridge running shortwave features offer additional thunderstorm chances while temperatures trend back to 90F.

MARINE...

Compact low pressure tracks east across Saginaw Bay and central Lake Huron early this morning bringing scattered thunderstorms. Gusty west wind will overspread western Lake Erie into Lake St. Clair this morning and a Small Craft Advisory is in effect. The cold front then pushes across the area through the rest of the morning with gusty northwest wind ensuing in its wake. This will reach the 20 to 25 kt range during the late morning and afternoon with waves in excess of 4 feet developing over parts of Lake Huron. These waves are likely to impact parts of the nearshore around the tip of the Thumb and a Small Craft Advisory is in effect there as well. Winds then gradually veer around to the north-northeast this evening while decreasing to 15 knots or less. Broad high pressure builds into the area on Friday, promoting light and variable winds. Southerly wind arrives on Saturday to bring the next humid and unstable air mass back into the region.

DTX WATCHES/WARNINGS/ADVISORIES
MI...Beach Hazards Statement until midnight EDT tonight for MIZ049.

Lake Huron...Small Craft Advisory until midnight EDT tonight for LHZ421-441>443.

Small Craft Advisory until 4 PM EDT this afternoon for LHZ422.

Lake St Clair...None.
Michigan waters of Lake Erie...None.