106
FXUS63 KDVN 081049
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
449 AM CST Mon Dec 8 2025

.KEY MESSAGES...

- An active pattern continues this week with several storm
  systems passing near or over the area with some chances for
  precipitation. However, the overall precipitations will be
  light.

- If surface temperatures don`t recover as forecast on Tuesday
  into Tuesday night, light freezing rain is possible across the
  area.

- Windy conditions are possible Tuesday night into Wednesday
  morning with gusts up to 40 mph possible.

- Another surge of arctic cold will settle into the Midwest for
  the end of the week and weekend. This arctic cold is be
  monitored for any potential cold headlines.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 201 AM CST Mon Dec 8 2025

A weak shortwave trough continues to move across the area early
this morning and producing clouds and a few flurries as it
moves eastward across the area. Temperatures at 2 AM remain in
the single digits above and below zero with light winds. Wind
chills have been as low as -15.

This shortwave is forecast to exit to the east early this
morning with winds turning to the south through the day. Today
will not be as cold as yesterday with high temperatures in the
lower to mid 20s.

Cloud cover will increase Monday night as another shortwave
passes to our north and grazes are far northwest Illinois
counties with light snow or flurries. Additionally, winds are
forecast to strengthen tonights with gusts up to 20 knots and
not much change in temperatures from today with lows in the
upper teens to lower 20s.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 201 AM CST Mon Dec 8 2025

Northwest flow aloft is forecast to continue across the region
through the remainder of the long term period with several
shortwaves/clippers passing through the area or nearby.

The shortwave from Monday night is forecast to shift to the east
on Tuesday. There is some uncertainty with the forecast on
Tuesday as winds turn to the south with speeds of 10 to 15 MPH
and gusts up to 20 MPH through the day. Models show
considerable warming across the area on Tuesday with high
temperatures ranging from the upper 30s along the Highway 20
corridor to the mid 40s in far northeast Missouri, far southeast
Iowa, and west central Illinois. The NBM has 50 to 90 percent
probabilities across the area over 40 degrees with the highest
probabilities across the south. However, snow cover across the
region may limit this warming with some models limiting high
temperatures area wide to the 30s. There will also likely be a
very shallow inversion across the area as well which may limit
winds.

Another shortwave trough is forecast to move across the area
Tuesday night and bring a cold front across the area by 12 UTC
on Wednesday. Model soundings show another strong inversion
across the area with very strong winds within the inversion.
Model soundings do show this inversion mixing out behind the
front with very deep mixing occurring across the area and the
potential to access 50 to 65 knots in a 5000 to 7000ft layer if
this mixing does occur. Increased winds Tuesday night into
Wednesday morning with the NBM 90th percentile winds with winds
gusting to near 40 MPH especially Tuesday night.

Due to the temperature forecast, models have precipitation
beginning as a mix before quickly changing over to all rain. Forecast
rainfall amounts are light with most locations receiving a
tenth of an inch or less. However, areas with snowpack will
behave like the surface temperature is at freezing with some
accumulation of ice possible. This will be something to keep an
eye over the next couple of days.

Wednesday night through Thursday night
Assessment...medium (40-60%) confidence on light accumulating snow
occurring

All global models show a weak upper level disturbance moving through
the area late Wednesday night into Thursday. The Boehmke rule is
satisfied, thus the precipitation will be in the form of snow.

In looking at the NBM 10-90th percentiles, the maximum water
equivalent would be around 0.10 inches with a higher probability of
it being less. With overnight temperatures expected to be in the
teens, the snow has a higher probability of being the dry, fluffy
type (i.e. rain/snow ratios greater than 12 to 1). In using the mean
water equivalent of 0.03 inches, such a ratio would translate into
just under an inch of accumulation for the likely max amount. Most
areas would thus see a dusting of accumulation.

There are timing differences between the models which translates
into on 30-50 percent chances for snow. I fully expect the snow
chances to slowly increase as the week progresses.

The bulk of the snow looks to be during the day Thursday with snow
beginning late Wednesday night and ending Thursday evening.

Friday through Sunday
Assessment...a certainty (>99% confidence) of another arctic surge
into the Midwest

The global models show another arctic surge into the Midwest for the
end of the week and into the weekend. The trigger will be the
passage of an arctic cold front either very late Thursday night or
during the day on Friday.

The strength of the arctic surge associated with the front raises a
strong potential for flurries or snow showers along with wind gusts
of at least 30 mph. Right now the model consensus has Friday dry but
I suspect this will change as the week progresses.

After the arctic front passes, well below normal temperatures will
be seen Friday night through Sunday. The wind will be slow to
diminish Friday night. The situation needs to be watched but the
potential is there for cold headlines Friday night into Saturday and
again Saturday night into Sunday. Of the two nights, the probability
of a cold headline is higher for Friday night than it is for
Saturday night.

The Friday night through Sunday time frame will be mainly dry.
However, there is a weak upper level disturbance that will move
through the area Saturday night that could produce light snow or
flurries. This far out the signal is quite weak but the model
consensus is generating 15 percent chances for light snow.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 419 AM CST Mon Dec 8 2025

A MVFR deck with ceilings around 3 KFT contiunes to slowly move
westward from Illinois into KMLI and KDBQ. Satellite trends show
these clouds slowly eroding from the east and expect VFR
conditions to develop by 15 UTC areawide. Current light and
variable winds will turn to the south from west to southeast by
18 UTC and increase to 5 to 10 knots. After 00 UTC, winds will
become southerly and increase to 10 to 15 knots with the
potential of gusts up to 25 knots overnight. A disturbance
moving passing to our north after 00 UTC will bring MVFR
ceilings to KCID, KDBQ, and KMLI overnight. KBRL is forecast to
remain VFR through the period.

&&

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

&&

$$

SHORT TERM...Cousins
LONG TERM...Cousins
AVIATION...Cousins