725
FXUS63 KLOT 040516
AFDLOT

Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
1216 AM CDT Sun Oct 4 2026

.KEY MESSAGES...

- Dry weather with seasonable temperatures are expected through
  much of the upcoming week.

&&

.DISCUSSION...
Issued at 1251 PM CDT Sat Oct 3 2026

The sun is shining and a look out the window (and most area
webcams) show the sky with a brilliant blue color. Temperatures
have climbed into the mid 60s under the sunshine with upper 60s
expected for the high temperature today. GOES satellite water
vapor imagery shows an amplifying wave over the eastern Dakotas
and west-central Minnesota presently. Showers and isolated
storms accompany the reflected surface front with the wave and
are expected to track east through the overnight. The forecast
leaned on the HRRR/RAP solutions (as they are doing a pretty
good job at current conditions in the northern Plains) which
keeps most, if not all, of the precipitation in Wisconsin
tonight. A sliver of slight chance PoPs were kept in the
northern tier counties just south of the Wisconsin state line,
but given the amount of dry air over Illinois, confidence is
higher in just a few sprinkles compared to a wetting rain.
Soundings show lapse rates aloft that are not terrible
overnight, but instability should weaken as the system crosses
the Mississippi River keeping the risk for lightning at bay. The
system should mostly pass over harmlessly, switching southeast
winds to the northwest behind the front and ushering in a
cooler, drier air mass.

Any mid-level cloud cover that moves over northern Illinois
tonight with the system should help quell any localized shallow
fog chances tomorrow morning. As winds turn to the northwest,
temperatures will fall into the low 40s. Given the northerly
flow expected tomorrow, high temperatures were nudged down
slightly, but with cloud cover decreasing through the day,
temperatures should once again return to the upper 60s with
areas along and south of I-88 reaching the low 70s. Clearer
skies are expected tomorrow night which will help drop
temperatures back down to the low 40s with rural areas having a
better chance at touching the upper 30s.

Seasonable temperatures will prevail through the week. High pressure
will help maintain mostly drier conditions, although another
wave over the northern Plains heading to Wisconsin mid-week
will be monitored. Guidance continues to favor the track of the
system north of Illinois so, for now, no precipitation is in the
foreseeable future.

DK

&&

.AVIATION /06Z TAFS THROUGH 12Z MONDAY/...
Issued at 1216 AM CDT Sun Oct 4 2026

A fast-moving disturbance continues to shift eastward across
the region. A few sprinkles will be possible as an arcing NE/SW
band of mid-level cloud cover drifts east across the Chicago-
area terminals through late tonight and will show brief VCSH
mentions at ORD, MDW, and DPA to account for this.

Winds are becoming southerly at this time and will slowly veer
out of the southwest overnight before turning out of the
northwest with the passage of a cold front after daybreak. A few
intermittent gusts up to 20 kts will be possible at times, but
look too infrequent to add at this point. Light NW winds will
then continue through the night into Monday morning.

Carlaw

&&

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

&&

$$

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