Romeoville, Illinois 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

213
FXUS63 KDVN 241116
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
516 AM CST Wed Dec 24 2025

.KEY MESSAGES...

- Above normal temperatures will continue through Saturday.

- Today will see increasing low level moisture, with drizzle and
  fog possible into Christmas Day.

- A brief period of sharply colder weather is expected Sunday &
  Monday.

&&

.SHORT TERM /THROUGH THURSDAY/...
Issued at 233 AM CST Wed Dec 24 2025

Quiet conditions overnight initially favored fog formation, but
increasing high clouds have helped limit radiational cooling,
and given our lack of snow cover, we have not crashed beyond
cross-over temperatures in many areas as of 2 AM. Thus, today
will continue to focus on the advection of moisture over top our
relatively cool air mass. From a broad view, this situation
should generate widespread low clouds, damp conditions, and
possibly dense fog in the cool season, but looking at the latest
CAMs, fog formation is not as strongly favored as earlier
forecasts. Still, with a warm front set up just south of the CWA
today through Christmas, I think the message of damp, cloudy,
and seasonally mild is still highly confident.

Moisture will push north today, from mid morning to late morning
today. Thus, sunrise hours will be OK, but by around lunch, it looks
gloomy and by afternoon and evening, plenty of drizzle will be going
on as the warm front pushes north.  Tonight, I don`t see much lower
level lift, but with plenty of low clouds and some fog, it could
drizzling at times too. ...Essentially Rudolph`s Weather...

Christmas Day looks damp and gloomy for sure, but not as much of a
lock for dense fog as data showed in past model runs. Drizzle or
rain looks likely again in the evening, as a weak wave of low
pressure moves through our southerly counties. In addition, fog
may spread in Christmas night, a problem that could linger at
night until the upcoming cold front.

Highs today and Christmas day appear near 40 in the north, and in
lower 50s in the south area.  Overnight temperatures in the lower
30s north to lower 40s south area expected.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Issued at 233 AM CST Wed Dec 24 2025

The mild pattern is expected to confidently last through Saturday,
ahead of a strong cold front and low pressure over the Great Lakes,
with highs in the upper 40s to upper 50s/low 60s on track Friday and
Saturday. With cloud cover continuing to be over the area in the
overnight hours, lows in the mid 30s to upper 40s should be be
expected Thursday night.

A progressive, but rather strong shot of cold air is expected to
sweep through the upper Midwest Saturday night through Monday, with
sharply colder temperatures and lows in the + single digits (we`d be
well below zero if we had snow cover). Highs Sunday and Monday are
expected to be in the 30s, and 20s. Though potent, this shot of cold
air is already modifying through the mid part of next week. Highs
returning to the upper 20s to mid 30s are expected.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 501 AM CST Wed Dec 24 2025

VFR conditions will start the TAF period, but we will start to
see conditions deteriorate through the day as a system
approaches the area. This weak system will bring through low
cigs, with light rain and drizzle possible as well. Between
15-18z, we will see MVFR cigs (1500-2500 ft)move in from
southwest-northeast, with IFR cigs moving in after 18z. Best
chances for LIFR cigs will be in areas of light rain/drizzle,
especially after 21z this afternoon. After 00z this evening, we
will continue to see cigs between 500-1000 ft, with fog
developing throughout the area. There remains some uncertainty
on the timing of fog, but we can expect a steady decrease in vis
between 00-06z. These conditions will remain until at least 12z
Thursday.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...None.
IL...None.
MO...None.

&&

$$

SHORT TERM...Ervin
LONG TERM...Ervin
AVIATION...Gunkel