Marine Weather and Tide Forecast for Lake Forest, IL

DISCUSSION
Issued at 215 AM CST Sun Nov 8 2026

Steady southwest winds along with an approaching axis of high clouds should limit further cooling overnight, with temperatures remaining more or less where they are at, in the lower 30s (rural low spots) to lower 40 (Chicago and along the lakeshore). Winds are expected to become increasingly breezy prior to daybreak ahead of a weak cold front, owing to earlier mixing into a low-level jet overhead. Winds turn more westerly behind the front later this morning, remaining breezy with occasional gusts up to 20-30 mph through sunset.

Upper ridging quickly builds back across the Upper Midwest today bringing a return of above normal temperatures through the first part of the week along with continued dry conditions.
Expect high temperatures in the upper 50s to around 60 today and Monday with low to mid 60s on Tuesday. Toward midweek, the northern stream upper jet begins to sag farther south which will allow a deepening shortwave trough to move across the area, bringing our next chance of showers (20-30 percent) on the north side of an associated developing surface low over central Illinois.

Ensemble guidance continues to support upper troughing and an eventual closed upper low developing across the eastern CONUS late in the week as a series of embedded shortwaves rotate over the broader Great Lakes region. In addition to bringing a return of cooler (more seasonable) temperatures locally, there remains a signal for lake effect precipitation developing over southern Lake Michigan during the late Wednesday night through Friday timeframe. The low-level flow orientation (and accordingly if and where the band sets up) will be dependent upon the strength and location of the deepening surface low to our east and the surface high over the northern Plains. These details are difficult to pin down this far out and will continue to monitor trends over the next few days. An early look at model soundings indicate the window for sufficient saturation within the DGZ may be very brief (if it occurs at all), which paired with the warm ground temperatures would likely limit or prevent any snow accumulations. Nevertheless, it does look like some locations near the lake could see their first snowflakes of the season.

Petr

AVIATION /12Z TAFS THROUGH 18Z MONDAY/
Issued at 519 AM CST Sun Nov 8 2026

There are no significant aviation forecast concerns for the current TAF period at this time.

Breezy westerly winds are expected today with gusts peaking at around 25 kts before the gustiness abates towards sunset. Some model guidance is hinting at a potential for fog late tonight into Monday morning, mainly near RFD and DPA. However, confidence in this fog developing and affecting the terminals is low at this time. Otherwise, VFR conditions are expected throughout the TAF period.

Ogorek

LOT WATCHES/WARNINGS/ADVISORIES
IL...None.
IN...None.
LM...Small Craft Advisory until 6 PM CST this evening for Winthrop Harbor IL to Burns Harbor IN.

Small Craft Advisory from 9 AM this morning to 3 AM CST Monday for Burns Harbor to Michigan City IN.