textproduct: Chicago

KEY MESSAGES

- Temperatures will remain generally above average through the upcoming 7 days.

- Aside from a chance for rain well south of I-80 Saturday night, primarily dry weather is in store until precipitation chances return midweek next week.

DISCUSSION

Issued at 245 PM CST Thu Feb 12 2026

An early spring-like weather pattern will set up over the next week for the region, favoring above to at times well above normal temperatures, though with variability in the details.

Tonight through Saturday Night:

Tonight will feature above average but relatively chilly temperatures (20s) as surface high pressure slowly shifts eastward. Friday will the warmest day for the area as a whole since back prior to the 3-week long cold stretch from mid January into the start of this month. With no snow cover, plenty of sunshine, modestly breezy southwest winds (especially southeast 1/2 to 2/3 of the area), and sub-freezing dew points, setup looks prime for temps in range of the warmest guidance. This supported highs in the low-mid 50s in the grids. Decent radiational cooling Friday night coming off the mild afternoon will yield lows in the upper 20s to lower 30s.

On Saturday, east-southeast winds along the Illinois shore will result in notably cooler temps (low 40s) than on Friday. Away from the IL shore, our forecast highs are similar to those of Friday, though mid and high level overcast may keep things a bit cooler than currently depicted. A southern stream short-wave will track well south of our area this weekend. Rain on the northern periphery of the system would reach into areas well south of I-80 (primarily near/south of the IL and Kankakee Rivers) Saturday evening and overnight if the consistently farther north ECMWF/EPS mean solution comes to fruition. Meanwhile, most of the remainder of the guidance has continued to favor even southern sections remaining dry. Even in a EC/EPS scenario, there likely would be a very sharp cut-off north of wherever the northern periphery of the rain sets up. As such, a gradient from ~40-50% PoPs south of US-24 to less than 15% near/north of I-80 appears reasonable.

Sunday through Thursday:

Sunday will be another unseasonably mild day away from Lake Michigan, reaching the mid to locally upper 50s. A lake breeze shifting inland during the afternoon will limit highs to the upper 40s to lower 50s near the lake, cooling to the low-mid 40s behind the lake breeze. Following a mild Sunday night (low-mid 30s), Monday looks quite mild based on progged 925 mb to 850 mb temps, though mid and high cloud cover may keep things in check, relatively speaking, with the official forecast (mid- upper 50s) still about 20 degrees above average. The question into Tuesday is whether a weak cold front pushes takes on backdoor characteristics and settles southward, which will have large implications on temperatures, especially closer to the lake.

The main weather of interest next week will come Wednesday through Thursday as trough ejection from the southwest results in broad lee cyclogenesis over the central and northern High Plains. As is to be expected, there's plenty of uncertainty in the regarding the specific evolution of key features at the surface and aloft. The position and trajectory of the dominant/consolidated surface low will determine how much of the area gets into the exceptionally mild warm sector on Wednesday (highs well into the 60s). Precipitation wise, showers (with a non-zero chance for elevated convection) are possible near or north of the system warm front Tuesday night into Wednesday morning.

A cold front should move across the area sometime on Wednesday, knocking temps down some on Thursday. Details are quite muddy late in the workweek, with a signal for a follow-up short-wave that may arrive as early as Wednesday night into Thursday. Note that any deeper synoptic system later next week will likely have well above average moisture content to work with, problematic for any areas that see heavy rain on top of thawing out but still frozen ground. Given the large ensemble spread, PoPs on Thursday are only in the 20-30% range for now.

Castro

AVIATION /00Z TAFS THROUGH 06Z SATURDAY/

Issued at 520 PM CST Thu Feb 12 2026

No significant aviation weather concerns for the 00Z TAFs.

Weak surface high pressure will drift off to the east of the terminals tonight, with a period of light/variable winds (easterly with a slight lake breeze enhancement this evening for ORD/MDW). With the surface high east of the area Friday, winds will turn southwesterly around 10 kts with a few gusts into the mid-upper teens possible during the afternoon. Any gusts should end with sunset Friday evening. Otherwise, VFR, mainly clear conditions are expected throughout the forecast period.

Ratzer

LOT WATCHES/WARNINGS/ADVISORIES

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