textproduct: Chicago

KEY MESSAGES

- Low chance for showers for northwest IN tonight/Sunday morning.

- Near record high temps possible and gusty southwest winds Monday.

- Active pattern next week with a series of cold fronts, precipitation chances and then turning colder into next weekend.

DISCUSSION

Issued at 201 AM CDT Sat Oct 10 2026

Despite mostly clear skies early this morning, temps are holding in the mid 50s to lower 60s thanks to strong low level winds just above the surface. Temps will likely remain nearly stationary until daybreak and begin a steady climb into the lower 80s for highs today for most locations. Southerly winds will gust into the 20-25 mph range at times today and favor a southeasterly direction this afternoon, which will keep temps cooler near the IL Lake Michigan shore.

The remnants of Isaias are expected to pass generally east of the local area with perhaps just a few showers across northwest IN tonight into Sunday morning and its possible much of northwest IN will remain dry. Low temps tonight look to drop into the 50s for most areas. Temps will be a few degrees cooler on Sunday for the eastern parts of the cwa and easterly winds may keep areas near Lake Michigan a few degrees cooler, but temps well inland across the western parts of the area may still reach the upper 70s/near 80 Sunday afternoon.

An upper ridge will build across the area Sunday night into Monday bringing a very warm day to the region as high temps are expected to reach the lower to mid 80s across the entire area. Southwest winds may also gust into the 20-30 mph range. A possible limiting factor for both the temps and the winds will be cloud cover. But with low temps only dropping into the upper 50s/lower 60s by Monday morning, highs in the lower/mid 80s is certainly possible and in line with guidance. If these temps were to materialize, they will be close to record highs for October 12.

A cold front is expected to move across the area starting early Tuesday morning and then likely pushing south of the area by early/mid afternoon. Its speed/timing will have a large impact on temps which may still reach the upper 70s/lower 80s across the southern cwa. Precipitation chances look fairly low during this time period, but a few showers and possibly a few thunderstorms are possible. Still appears a storm system will develop over the Plains midweek, which will lift a warm front back across the area with one or two cold fronts moving across the area late next week. Still quite a bit of uncertainty for how this will all unfold, but the ensembles still show good consistency for a push of much colder air next weekend. cms

AVIATION /06Z TAFS THROUGH 12Z SUNDAY/

Issued at 1226 AM CDT Sat Oct 10 2026

Forecast concerns for the terminals...

- Low-level wind shear threat tonight

- Occasionally breezy winds Saturday afternoon with gusts around 20 kt possible

Mid-level ridging is spreading over the Midwest and Great Lakes which will keep dry and generally quiet weather in store for this TAF period. However, a stout (30-40 kt) low-level jet has developed overhead and is generating some low-level speed and directional shear around 1500 ft AGL. The jet is forecast to weaken towards daybreak which will allow the threat for LLWS to wane.

Otherwise, expect increasing VFR cirrus clouds through the period as the blow-off from the tropical system in the southern CONUS drifts overhead. While it does look like winds will increase Saturday afternoon as the decaying tropical system nears the Ohio River Valley, the overcast skies look to limit overall mixing which may make gusts more infrequent. Therefore, have opted to forego any gusts in the TAFs but some occasional 18-22 kt gusts will be possible. Regardless, directions will remain southeasterly through the period.

Yack

LOT WATCHES/WARNINGS/ADVISORIES

IL...None. IN...None. LM...None.