Peotone Weather

National Weather Service Forecast for: Peotone, IL Issued by: National Weather Service Chicago/Romeoville, IL

Updated: Thu, 27-Aug-2026 1:35am CDT

- Select Forecast - Peotone, IL Manteno, IL Beecher, IL Monee, IL Kankakee, IL Willmington, IL Braidwood, IL Manhattan, IL OakForest, IL Stelle, IL Ottawa, IL Amboy, IL Byron, IL Rockford, IL Quad Cities, IL Champaign/Urbana, IL Peoria, IL Bloomington, IL Springfield, IL Carbondale, IL Vienna, IL Culver, IN

Peotone, IL

Thursday Patchy Fog then Slight Chance Rain Showers Friday Patchy Fog then Sunny Saturday Mostly Sunny Sunday Mostly Sunny Monday Slight Chance Rain Showers then Mostly Sunny Tuesday Chance Showers And T-Storms then Slight Chance Showers And T-Storms Wednesday Chance Showers And T-Storms then Slight Chance Showers And T-Storms   Hi 80 °F Hi 81 °F Hi 80 °F Hi 86 °F Hi 88 °F Hi 88 °F Hi 87 °F   Overnight Patchy Fog Thursday Night Partly Cloudy then Patchy Fog Friday Night Partly Cloudy Saturday Night Mostly Cloudy Sunday Night Partly Cloudy then Slight Chance Rain Showers Monday Night Partly Cloudy then Chance Showers And T-Storms Tuesday Night Partly Cloudy then Chance Showers And T-Storms   Lo 64 °F Lo 60 °F Lo 59 °F Lo 65 °F Lo 70 °F Lo 70 °F Lo 70 °F

Forecast from NOAA-NWS for Peotone, IL.

129
FXUS63 KLOT 270806
AFDLOT

Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
306 AM CDT Thu Aug 27 2026

.KEY MESSAGES...

- Increasing heat and humidity is expected next week with
  periodic shower and storm chances.

&&

.DISCUSSION...
Issued at 306 AM CDT Thu Aug 27 2026

Surface high pressure continues to expand across the region
early this morning in the wake of yesterday`s cold front. This
will lead to a period of largely quiescent weather through the
end of the week. A lake breeze is expected to push inland today
which may provide enough lift for a few spotty showers or
sprinkles as a weak disturbance moves across the area (15%
chance). Coverage should remain very isolated if they even
develop given limited moisture availability and shallow cloud
depths. Otherwise rain-free weather is in store across the area
through at least Saturday afternoon with highs in the upper 70s
to lower 80s and comfortable humidity.

Mostly clear skies early this morning and again tonight may
allow for sufficient radiational cooling for shallow patchy fog
development, particularly along river valleys and typical fog
prone low spots outside of Chicago.

Looking ahead, the upper level pattern begins to transition
toward upper ridging building across the central CONUS with
multiple waves expected to traverse the Northern Plains and
Upper Midwest this weekend through much of the upcoming week.
The first of these waves may arrive as early as Saturday
night in the form of a decaying convective complex. Latest
guidance suggests that if this convection forms upstream it
would likely be outrunning the unstable airmass with southeast
extent and residual low-level dry air across the area would
likely limit the coverage of lightning or any potential severe
weather here locally.

The degree of heating as well as our shower and thunderstorm
chances for much of the upcoming week will be dependent upon the
strength of the aforementioned upper ridge. A stronger ridge
would result in warmer (potentially highs in the 90s) and more
humid conditions with the focus for greater thunderstorm
coverage ending up north of the area. In contrast, a weaker
upper ridge would support warmer conditions but to a lesser
degree (mid-upper 80s) paired with frequent rounds of showers
and thunderstorms. Suspect we may end up somewhere in between
these two scenarios and will continue to refine the details as
it gets closer. Stay tuned.

Petr

&&

.AVIATION /06Z TAFS THROUGH 12Z FRIDAY/...
Issued at 1247 AM CDT Thu Aug 27 2026

Forecast concerns for the terminals...

- Patchy fog possible near the Kankakee River Valley tonight.

- Lake breeze to result in an easterly wind shift at Chicago
  area terminals Thursday afternoon.


High pressure continues to settle into the Midwest and is
expected to remain in control over our weather through the TAF
period. Therefore, expect light northwest winds around 5-10 kts
to prevail through much of the period, though a lake breeze
will result in an easterly wind shift at ORD, MDW, and GYY
Thursday afternoon. Guidance is in generally good agreement on
the lake breeze arriving at ORD and MDW between 19z and 21z
(around 16-17z at GYY) but as is typical suspect some shifts in
timing may occur as we get closer. Winds will then become more
light and variable Thursday night as the center of the high
passes overhead. Otherwise, expect VFR conditions to prevail
through the forecast period.

While there is a chance (15-20%) for some shallow fog (3-5 mile
visibilities) to develop near and south of the Kankakee River
Valley tonight, it seems any fog should remain generally south
of the TAF sites. Finally, there is also a non-zero (10-15%)
chance for an isolated shower to develop along the lake breeze
Thursday afternoon. Given that moisture depths are somewhat
shallow confidence on shower coverage is too low to warrant a
TAF mention, but did introduce a BKN050 mention to the Chicago
terminals and GYY to tease this potential.

Yack

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...None.

&&

$$

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