Romeoville, Illinois 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

582
FXUS63 KDVN 060952
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
352 AM CST Sat Dec 6 2025

.KEY MESSAGES...

- A fast moving storm system is forecast to bring snow as well
  as mixed precipitation to the area Saturday night into Sunday
  morning. The winter weather advisory has been expanded to the
  south and east.

- Active northwest flow aloft is forecast to continue next week
  with the main storm track near the area. This will bring
  chances of precipitation every 36 to 48 hours.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 246 AM CST Sat Dec 6 2025

There are significant changes to the track of the upcoming fast
moving shortwave for tonight into Sunday morning resulting in
changes to the forecast for Saturday night. The GFS, ECWMF, and
Canadian have maintained a similar track to previous runs while
the NAM and CAMS have tracked farther to the north. The farther
north solutions are leading to precipitation type issues and
changes in amounts as the northward shift in the track allows
warmer air to be pulled into the area. Overall this reduces
forecast confidence in amounts and precipitation types across
the area especially for area south of Interstate 80.

The GFS, ECWMF, and Canadian have snow falling areawide with a
wintry mix along and south of a Fairfield to Galesburg line as
the shortwave and surface low track across northern Missouri.
This results in a widespread 2 to 4 inches of snow north of this
line with 1 to 2 to the south along with the possibility of a
glaze of ice. This more southern track also results in 5 to
possibly 6 inches of snow along the Highway 20 corridor. If this
solution looks more likely, further changes to the headlines are
possible along the Highway 20 corridor.

The NAM and CAMS have the shortwave and attendant surface low
tracking across southern Iowa now. This pushes the mixed
precipitation northward to along the Interstate 80 counties
during the evening hours with 1 to 3 inches of snow and 3 to 5
inches farther to to the north. A glaze of ice is possible
along and south of Interstate 80. After 06 UTC as the surface
low moves to the east of the area, cold air being drawn into the
system changes precipitation over to all snow quickly from
north to south.

All models have precipitation beginning around 00 UTC west of
the Mississippi River and expanding east of the river by 3 UTC.
Precipitation intensity areawide increase after 3 UTC or 9 PM
as large scale ascent increase and overspread the area. For
these reasons, made the decision to expand the winter weather
advisory to the south and east and across the area. SREF
probabilities show snowfall rates approaching 1 inch per hour so
snow may accumulate quickly for a time overnight.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 246 AM CST Sat Dec 6 2025

Overview: The storm track will remain over the area through the
long term period with the storm track (jet stream) meandering
back and forth with each passing clipper system. There is a
clipper forecast roughly every 36 to 48 hours that will produce
mainly light precipitation/snow chances as they pass near or
across the area.

Sunday On:

Snow is forecast to come to an end from west to east after 12
UTC Sunday. NW winds will increase behind the departing low and
could reach 20-30 mph, leading to some blowing and drifting snow
in open and rural areas. The gusty winds will advect a colder
air mass into the region with highs in the teens and 20s, and
overnight lows in the single digits above and below zero.

Warmer air will be drawn northward on Tuesday and Wednesday
ahead of another clipper that is forecast to move across the
area for the middle of the week. This will result in high
temperatures on Tuesday and Wednesday in the 30s with warmer
temperatures lingering into Tuesday night before the front moves
across the area. This system will pass farther to the north
than the one on Saturday night and depending on the track may
result in more of wintry mix across the area but this will
ultimately depend on the track of this system. Colder air will
spread back into the area behind this system.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1137 PM CST Fri Dec 5 2025

MVFR to possibly IFR ceilings are forecast to linger at eastern
Iowa TAF sites through 12 UTC. IFR ceilings are more likely at
kDBQ overnight then at the other locations. Guidance shows a
slight lifting of ceilings after 12 UTC but MVFR conditions
continuing through the day. Conditions are forecast to
deteriorate again after 00 UTC on Sunday as a storm system
spreads snow into the area from west to east. IFR conditions
are possible after 03 UTC but may hold off until later as more
intense snowfall overspreads the area overnight. Northwest
winds around 10 knots are expected overnight before turning to
the east after 21 UTC ahead of the snow. A wintry mix is
possible at KMLI and KBRL after 00 UTC but confidence is low in
this occurring at this time so it was left out of the TAFs for
this issuance.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...Winter Weather Advisory from 6 PM this evening to 6 AM CST
     Sunday for IAZ040>042-051>054-063>068-076>078-087>089-099.
IL...Winter Weather Advisory from 6 PM this evening to 6 AM CST
     Sunday for ILZ015-024>026-034-035.
     Winter Weather Advisory from 9 PM this evening to 6 AM CST
     Sunday for ILZ001-002-007-009-016>018.
MO...None.

&&

$$

SHORT TERM...Cousins
LONG TERM...Cousins/Uttech
AVIATION...Cousins