868
FXUS63 KDVN 181058
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
558 AM CDT Sat Oct 18 2025

.KEY MESSAGES...

- A Dense Fog Advisory is in effect until 10 AM this morning
  west and northwest of the Quad Cities.

- There are periodic chances for showers and thunderstorms into
  early Sunday morning.

- Windy conditions are expected tonight into Sunday, and again
  on Tuesday.

- Seasonable mid to late October weather is forecast for much
  of next week with no significant precipitation expected.

&&

.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 300 AM CDT Sat Oct 18 2025

Today:

A potent 500mb shortwave/vorticity max will dig into the
Central Plains and lower portion of the Midwest. This will lead
to cyclogenesis across the Lower Great Lakes region and focus
the heaviest rainfall to our east across portions of central to
eastern Illinois into much of Indiana and Lower Michigan. Across
eastern Iowa and northwest Illinois, expect a warm and quiet
day with highs in the lower to upper 70s.

Another round of showers and possibly embedded/scattered storms
is expected to develop tonight as large-scale ascent increases
in association with the aforementioned sharp mid-level wave. The
steadier rain and therefore the highest amounts are expected
east of the Mississippi River where a half inch or more is
possible. Lighter amounts of around 0.10" to 0.25" are more
likely west of the river. Some of the storms late this evening
through 11 PM tonight could be strong with the HREF showing 500+
J/kg of MUCAPE south and east of the Quad Cities. The primary
threats are gusty winds, hail, and lightning. As the low begins
to wrap up near/east of Chicago, the cold front and a tight
pressure gradient will surge through the region. This will
result in strong NW winds tonight gusting 30-40 mph, aided by
2-4mb/3hr isallobaric rises and cold air advection isentropic
downglide.

Sunday: Cooler and breezy (NW 25-35 mph) with highs in the
upper 50s to lower 60s. Certainly a more fall-like feel to the
day with the cooler temps and gusty winds!

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Issued at 300 AM CDT Sat Oct 18 2025

Another deep upper trough is forecast to dig into the Midwest
and Great Lakes early next week with an attendant surface low
tracking north of the local area across the Great Lakes. After a
brief warm up ahead of the trough on Monday, cooler more
seasonable temperatures are expected for the middle of the
week. We`ll stay on the drier and windy southwest flank of the
early week system, so rain chances will be on the low side for
Monday night into Tuesday (20-40%, highest in the northeast).
The surface low tracking across the Great Lakes will set up a
tight pressure gradient across Iowa and Illinois, leading to
strong NW winds gusting 30-40 mph through the day on Tuesday.

Frost is possible north of I-80 Tuesday night, which will
depend on how quickly a surface ridge builds in behind the
departing low. The NBM has lows in the mid/upper 30s with the
coldest temperatures across the north. Confidence remains low
due to uncertainty on lingering clouds and if steady NW winds
last through the overnight period. Temperatures trend back above
normal for late in the week.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 547 AM CDT Sat Oct 18 2025

Areas of fog, locally dense, will impact CID and DBQ this
morning through 14-15Z/Sat. Then VFR is expected to prevail
area-wide through the day, before the next round of showers and
isolated storms develops mainly after 00Z/Sunday, which may be
accompanied by brief MVFR. NW winds will quickly increase
tonight as a cold front surges through the region, with gusts
between 25-30 kts likely.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...Dense Fog Advisory until 10 AM CDT this morning for IAZ040>042-
     051>053-063>065-076-077.
IL...None.
MO...None.

&&

$$

SHORT TERM...Uttech
LONG TERM...Uttech
AVIATION...Uttech