Lake Thunderbird Illinois Weather Forecast Discussion

920
FXUS63 KDVN 071901
AFDDVN
Area Forecast Discussion
National Weather Service Quad Cities IA IL
201 PM CDT Tue Oct 7 2025
.KEY MESSAGES...
- Patchy frost possible late tonight along the Highway 20 corridor,
  with more widespread patchy frost potential Wednesday night
- Near-normal temperatures expected to continue through Thursday
  before another warm-up occurs by the upcoming weekend
- With the exception of Thursday night and late next weekend,
  another dry week is on tap for the area
&&
.SHORT TERM /THROUGH WEDNESDAY/...
Issued at 200 PM CDT Tue Oct 7 2025
The cold front that brought the first measurable rainfall in nearly
two weeks to our area has exited the region earlier this morning,
and a much more autumn-like air mass has moved in. Northerly flow
over the area has led to temperatures in the mid-60s across the area
this afternoon, which is much closer to normal for this time of the
year.
Tonight, a large area of high pressure will build across the western
Great Lakes region, expanding southward over the Corn Belt. Clear
skies tonight and light winds should result in a cool night, with
lows in the upper 30s north to the lower/mid 40s south. Given the
proximity of the high, combined with clear skies and light winds,
efficient radiational cooling is expected. With that said, decided
to trend tonight`s lows near the 25th percentile of the model
spectrum. There is the potential for some patchy frost late tonight,
mainly along the Highway 20 corridor.
Upper-level ridging and the high pressure system looks to dominate
the region for Wednesday, so expect another sunny and seasonal day,
with highs warming to the lower 60s north to the upper 60s
south.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Issued at 200 PM CDT Tue Oct 7 2025
Wednesday night looks to be yet another chilly night as the surface
high looks to strengthen over the Great Lakes region. The ECMWF
ensembles indicate MSLP values around 97% of climatology, with
central pressure around 1033 hPa, so quite a strong system. Another
favorable radiational cooling night is expected, and I have leaned
towards the 25th percentile once again for lows, which suggests lows
in the middle to upper 30s across the area. Patchy frost potential
looks to be slightly more widespread Wednesday night, with locations
along and north of Interstate 80 most favored.
Thursday through Sunday: the high pressure system looks to shift to
the east, with southerly return flow building back in Thursday. This
should result in a slight warm up, with highs in the middle to upper
60s. This warm-up will only continue, with highs back in the 70s by
Saturday, and even some lower 80s possible Sunday. In terms of
precipitation, chances appear to be pretty meager, with only a 10 to
30% chance of showers Thursday night into Friday morning per the NBM
via weak fropa. LREF ensemble soundings show quite a bit of dry air
below the 850 mb level, so measurable rainfall looks to be hard to
come by.
Next Monday looks like a (slightly) higher chance of showers (20-
40%) for Sunday night and Monday as another front approaches from
the west. This has a better potential for measurable rainfall over
the area, but timing details remain uncertain at this time.
&&
.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1215 PM CDT Tue Oct 7 2025
SKC will continue to expand across the area this afternoon, with
northerly winds around 10 knots. Winds will weaken this evening
into early Wednesday morning, remaining from the north to
northwest, and then turn more northeasterly during the daylight
hours Wednesday.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...None.
IL...None.
MO...None.
&&
$$
SHORT TERM...Schultz
LONG TERM...Schultz
AVIATION...Schultz

NWS DVN Office Area Forecast Discussion