Clinton, Iowa 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

286
FXUS63 KDVN 252338
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
538 PM CST Thu Dec 25 2025

.KEY MESSAGES...

- Dense fog likely to become widespread again tonight into
  Friday morning.

- A strong system will affect the area on Saturday night and
  Sunday with a period of showers and embedded storms (20-30%)
  followed by windy and much colder conditions arriving Sunday
  afternoon/night.

- Wind chills around zero to 15 below zero are forecast Sunday
  night and Monday morning.

&&

.SHORT TERM /THROUGH FRIDAY/...
Issued at 138 PM CST Thu Dec 25 2025

Low clouds and fog are making for a dreary Christmas day across
the region. Strengthening easterly winds occasionally gusting
to 20 mph is drawing dew points down into the 30s along and
east of the Mississippi River and north of I-80, which has
allowed for marked improvement in visibilities. However, fog
persists in our far west/southwest in the deeper moisture
(dew points in 40s) and weak low level convergence where it also
remains dense. Fog will likely set in elsewhere tonight and
likely widespread dense, but it`s unclear just how quickly
this will occur. But, as a weak surface low and attendant
low level convergence approach late this evening and overnight
do expect widespread dense fog necessitating an expansion of the
Dense Fog Advisory. Attendant theta-e advection should foster
burgeoning drizzle, and time-height cross sections would
indicate even the potential for deep enough saturation and lift
to support some light rain with low measurable amounts (few
hundredths of an inch) particularly across the northeast half of
the area. As the low moves through overnight temperatures will
rise through the 40s with 50s from QC metro especially
south/east. Then, as it departs Friday morning winds will shift
around from the northwest and this will usher in drier air
leading to the fog lifting by mid to late morning. Increasing
subsidence may bring about some cloud breaks but overall still
looks to be partly to mostly cloudy. Temps look to remain above
normal Friday with temperatures largely hanging around in the 40s
the rest of the day after the early morning peak.

&&

.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
Issued at 138 PM CST Thu Dec 25 2025

A transitory bout of low to mid level ridging will result in dry
conditions Friday night into Saturday. Soundings show the
potential for some low level moisture remaining trapped beneath
a subsidence inversion, which could support at least partly
cloudy skies. Extent of clouds will play pivotal role in
temperatures and given uncertainty felt NBM 50th percentile was best
to roll with for lows Friday night (mainly 30s). On Saturday, the
ridging will shift east allowing for increasing southerly return
flow/warm advection to commence leading to above normal
temperatures. Current forecast has 60s in the far south for highs
on Saturday with a gradient to cooler 40s in the far north.
These temperatures particularly south of I-80 could be a bit
optimistic especially with a signal for decent warm/moist advection
that will likely produce additional lower clouds.

Saturday night and Sunday the weather looks to turn active with
a sharp return of winter on Sunday. This is due to a 2 part system
with a northern stream trough digging through the Northern Plains
Saturday night, which continues to trend a bit slower and
stronger as it interacts with southern stream energy ejecting from
California. This will lead to a develop surface cyclone in the
Central Plains Saturday night that will quickly advance through the
region on Sunday. Increasing ascent associated with positive
vorticity advection and frontal convergence in concert with rapid
moisture advection aided by a veering S/SW LLJ 40+ kts should result
in a burgeoning rain shield that sweeps across parts of the service
area Saturday night/early Sunday. Currently the favored area is
roughly the southeast 1/3-1/2 of the service area. This should be a
fairly quick hitting slug of rain, but intensity could be moderate
to briefly heavy with amounts over 0.5 inch in spots as PWATs climb
to around 0.75 to 1 inch. Given the lack of frozen ground in this
area not anticipating much in the way of hydro issues. Can`t rule
out also some thunder with elevated instability advecting northward
into the region with the latest LREF depicting mean MUCAPE of 100-
200 j/kg into the south with up to 500 j/kg not too far away into
parts of central IL/MO.

Following the low will be a strong cold front by Sunday afternoon/
evening leading to plummeting temperatures on strong NW winds.
Bufkit soundings show around 40 kt atop the mixed layer and with
favorable momentum transfer via deep unidirectional flow and
cold advection we may be looking at advisory level gusts over
45 mph possibly. It looks as though we`ll have the potential to
see some light snow within an area of post-frontal mid level
frontogenesis. Question is whether this is just flurries or
could we see a period of light snow and minor accumulations for
some. Currently the indications are that much of the moisture
will be shunted off ahead of the cold air to where flurries would
appear to be favored. But, this remains something to watch given the
continued slowing of the system, which could allow for more moisture
to work with. The brunt of the cold arrives Sunday night into
Monday morning as temperatures bottom out in the single digits and
teens. Combine these with the brisk winds and it will feel
bitter cold with wind chills lowering into the range of zero to
15 below.

Monday through New Year`s Day, starting to see more consensus toward
a northwest flow pattern. This would support staying colder /near
normal/ and would favor periodic clipper systems. There is
however, considerable uncertainty on where the main baroclinic
zone and favored track of these clippers will lay out with seemingly
more consensus toward near or northeast of our area, which if occurs
would be mainly dry. Again, this is uncertain right now and can
change, so stay tuned especially if you have any New Year`s plans
across the Midwest and Great Lakes.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 528 PM CST Thu Dec 25 2025

MVFR to LIFR conditions to start the period low clouds and MVFR
visibilities at the TAF sites. Conditions are forecast to
deteriorate this evening as fog redevelops at area TAF sites and
ceilings further lower with widespread VLIFR conditions possible
especially between 3 to 12 UTC as a surface low moves across
the area and winds become light across the area. Once the
surface low passes to the east by 12 UTC Friday, winds will turn
to the northwest and visibilities begin to improve to MVFR late
morning into the afternoon. Ceilings will slowly improve after
18 UTC.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...Dense Fog Advisory until 9 AM CST Friday for IAZ051-063-
     076>078-087>089-098-099.
IL...Dense Fog Advisory until 9 AM CST Friday for ILZ025-034.
MO...Dense Fog Advisory until 9 AM CST Friday for MOZ009-010.

&&

$$

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