Marine Weather and Tide Forecast for Grosse Pointe Farms, MI

AVIATION

Dry and stable conditions maintained under the influence of lingering high pressure ensures VFR conditions persist tonight. Some intervals of thicker high based cloud may emerge at times, but skies will remain clear across the lowest 5000 ft. Modest winds from the northeast turning light/variable overnight. As winds become east- southeast, there remains some potential for higher low level moisture positioned over the eastern great lakes to lift toward the region Monday morning. This maintains a low probability for a period of lower cloud at high MVFR or low VFR to emerge early in the day.
Otherwise, another day of limited high based diurnal cu development beneath periodic thicker cirrus for Monday.

For DTW/D21 Convection... No thunderstorms expected through this TAF period.

THRESHOLD PROBABILITIES...

* None

PREV DISCUSSION
Issued at 339 PM EDT Sun Jun 15 2025

DISCUSSION...

Seasonable conditions persist into the evening with highs generally in the upper 70s to near 80 degrees in the Detroit Metro Area.
Exception to these temperature trends is around the Saginaw Valley and Thumb regions where a thin cloud deck held on through early afternoon to tamper daytime highs by a few degrees.

Broad upper level ridging takes control for the next few days, with the existing deformation axis eroding in its favor. The pattern shifts gradually to warmer and more humid conditions by mid-week, specifically as a train of shortwaves draw this airmass from the Mississippi River Valley into SE Michigan. Highs in the low 80s are expected Monday before 850 mb temperatures warm into the mid teens Tuesday and the upper teens Wednesday, equating to daytime highs at least in the upper 80s. A handful of LREF ensemble members project some urban areas could reach 90 degrees either day, but the temperature forecast will be highly sensitive to any convective cloud debris. This warmer airmass will be accompanied by return flow from the Gulf to push dewpoints into the mid to upper 60s, creating muggy conditions and priming the boundary layer for destabilization during peak heating each day.

Monday looks to remain mostly dry with a remnant subsidence inversion around 15.0 kft agl that caps convective prospects.
Surface pressure falls then commence late Monday night-Tuesday as a progressive northern stream shortwave attempts to phase with a slower cutoff low drifting toward the Ohio Valley. The latest 12z model suite keeps the two systems separate, which shears morning moisture transport to the south and east of the state line and effectively limits precipitation chances. The lagging surface trough then tracks through Tue afternoon-evening and takes of advantage of building surface-based instability. Lackluster wind shear will inhibit organized convection, although dry air entrainment may enhance downdrafts on an isolated basis to support gusty winds of 40+ mph in any storms.

Potential for organized convection increases Wednesday as strong synoptic forcing and wind shear overspread the Great Lakes. The caveat to this is how buoyancy evolves throughout the day Wednesday, as the Tuesday night wave looks to fully clear out existing instability. This is further complicated by possible MCS development Wednesday morning, with MCSs being notorious for disrupting theta-e transport. So while the global/regional models look fairly straightforward for Wednesday as of now, these types of setups can be tricky with all of the convective influence and mesoscale boundaries that can emerge. For now, this system passes the eye test for both a severe weather and heavy rainfall threat for the Wednesday afternoon-evening period. This is corrobated by national guidance, with a 15% outlook region from SPC and Marginal Excessive Rainfall outlook from WPC.

MARINE...

High pressure over eastern Canada maintains favorable marine conditions through this evening before drifting east across New England tonight. Light wind organizes out of the southeast on Monday but remnant ridging maintains dry and stable conditions. A warm front lifts into the Great Lakes on Tuesday which ushers in a warmer and more unstable air mass on moderate south wind. Showers and thunderstorms increase in likelihood by late in the day. An unsettled pattern persists through the rest of the week as a series of low pressure systems track through the region - showers and thunderstorms will be possible each day.

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