347
FXUS63 KDVN 180535
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
1135 PM CST Wed Dec 17 2025

.KEY MESSAGES...

- Rain likely early Thursday, with highest probabilities
  (40-60%) of greater than 0.25" amounts east of Mississippi
  River. Slight chance (15-25%) of afternoon/early evening snow
  showers, with rapidly falling temperatures that may create
  slick spots during the evening commute.

- Windy conditions Thursday afternoon and evening, with a 40-50%
  chance of wind gusts over 40 mph.

- Dry conditions are expected Friday through Tuesday, with some
  large temperature swings. A persistent trend of above normal
  temperatures will be seen next week.

&&

.SHORT TERM /THROUGH THURSDAY/...
Issued at 209 PM CST Wed Dec 17 2025

A mix of sun and clouds was seen today, with temperatures rising
above freezing area-wide allowing for some snow melt. Temperatures
at 1pm ranged from 33 degrees in Independence, to 41 degrees in
Fort Madison and Keokuk. Strong 977mb surface low was analyzed
over southern Alberta at 18z, which will drag a strong cold
front through the region Thursday morning.

Increasing clouds and southerly winds are forecast this evening and
overnight with slowly rising temps. Strong WAA and moisture
transport evident by PWs rising into the 0.6-0.8" range and
dewpoints rising into the lower 40s in our south will support
scattered rain showers blossoming just prior to daybreak Thursday.
Still can`t rule out a rumble of thunder or two as steep mid level
lapse rates will be present. CAMs have rain continuing for much of
the morning ending from west to east by early afternoon.

Attention then turns to the strengthening west northwest winds and
falling temps behind the cold front. 12z HREF ensemble max
probabilities have increased in the past 12 hours with sporadic 40kt
gusts at a few sites within the CWA. Bufkit soundings also show
44kts at the top of the mixed layer and with a strong pressure
gradient in place (6mb 3-hr pressure rises) will see wind gusts
between 35-45 mph during the late afternoon and evening. This
is just below Wind Advisory criteria and after collaboration
with neighboring offices have decided to hold off on any
headlines for now with just a few sites hitting criteria for an
hour or two. An SPS may at least be needed for this hazard
tomorrow. We still have some time to reevaluate the models
before these strong winds develop, so stay tuned for updates.

Strong CAA will also commence in the late afternoon and evening with
temperatures falling 6-7 degrees in under 2 hours behind the front.
Below freezing temperatures are expected and with the morning rain
washing away much of the salt or treatment on roads and sidewalks,
we could see some slick spots develop during the evening commute if
the winds don`t evaporate all the water from the roads. Motorists
should use extra caution tomorrow night while driving due to
possible icy conditions. In addition, there continues to be a
signal for snow showers mid afternoon/early evening. Strong low
level fgen combined with some weak instability off the RAP may
support a brief window of rather robust snow showers (snow
squalls?) sometime between 2-6pm. One thing going against this
possibility is the snow showers may outrun the colder air at the
surface (flash freeze component) to make for a higher threat.
Will continue to message snow shower and reduced visibility
potential during the Thursday evening commute and will ramp up
messaging in threat increases further in the next 24 hrs. Winds
will remain breezy overnight, dropping wind chills below zero
Friday morning.

&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
Issued at 209 PM CST Wed Dec 17 2025

The colder side of the Thursday storm system will continue to
progress through the area Thursday night, lingering chances (20-30%)
of snow showers in the evening and plunging temperatures with
continued gusty winds into Friday morning. The colder temperatures
and winds should couple with the snow showers to result in reduced
visibilities as well as slick road conditions due to wet roads
becoming icy. The latest HREF ensembles suggest gusts up to 45 mph
are still possible in the early evening, and the ECMWF EFI values
for wind gusts after 00z/6 PM Friday range between 0.7 to 0.9, which
is a good signal for strong wind gusts to continue from Thursday
afternoon. With all this said, hazardous travel is possible for the
evening commute - something to keep a close eye on. Friday morning`s
low temperatures should fall to the single digits above zero north
of Interstate 80, with lower/middle teens to the south. Widespread
wind chills should also fall between 0 to -15 degrees for most
locations, so be ready for a very cold start Friday morning. A high
pressure ridge axis will sweep through the area during the daylight
hours Friday, leading to southerly return flow building in behind
the ridging. This will help temperatures rebound in the afternoon,
with highs in middle 20s northeast to the middle 30s southwest.

Friday night through the rest of the weekend: we will see a few
systems pass near or over the local area, but a lack of moisture
will keep precipitation chances at bay. The first system will remain
north of the area where better moisture will remain. For us, this
will only result in some cloudy skies overnight. The other system is
progged in the form of a weak cold front, which looks to sweep
through the area during the day Saturday. Again, higher moisture
should remain north of the area, so only some cloudy skies are most
likely to result from the fropa. Temperatures will warm up to the
upper 30s north to the middle 40s south for highs Saturday. Another
cold night looks possible Saturday night in the wake of the front,
with lows dipping to the lower teens north to lower 20s south.

Monday and Tuesday: model solutions differ quite a bit regarding
precipitation chances for the early part of next week. However,
confidence is much higher for a warming trend, with the LREF
ensemble probabilities of daytime highs above freezing around 70-90+
percent for both Monday and Tuesday. For those of you hoping for a
White Christmas this year, these temperatures aren`t a good sign as
much of our snowpack is very likely to melt further if these
temperatures come to fruition.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1127 PM CST Wed Dec 17 2025

WSR-88D VAD profiles shows LLWS is well underway across eastern
Iowa and northern Illinois. SHRA will rapidly develop 09-12z/18
as the dry air gives way to saturation with CIGS quickly
dropping to MVFR. HRRR model shows a potential of wind gusts
35-40 knots during the first frontal passage 12-17z/18.
Secondary front to bring another jump in sustained winds with
gusts up to 40 knots. 10-30 percent coverage of SHSN 21z/18
through 03z/19 have the potential of brief IFR/LIFR conditions
if they impact a TAF site.

&&

.CLIMATE...
Issued at 1204 PM CST Tue Dec 16 2025

A broad and anomalous 500mb ridge (588 dm or 99th percentile
per climatology for late December) will be across the central
CONUS next week. The 8-14 day temperature outlook from the
Climate Prediction Center shows 85-90% combined probabilities of
near/above normal temperatures for the December 23rd-29th time
frame. Normal highs for this period are in the lower 30s and
normal lows are in the middle teens. Should see some substantial
melting take place before and during Christmas across the
forecast area.

&&

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

&&

$$

SHORT TERM...Gross
LONG TERM...Schultz
AVIATION...08
CLIMATE...Gross