Thomas, Illinois Weather Forecast Discussion

048
FXUS63 KDVN 251121
AFDDVN
Area Forecast Discussion
National Weather Service Quad Cities IA IL
621 AM CDT Thu Sep 25 2025
.KEY MESSAGES...
- Patchy fog this morning, some of which could become dense
  mainly in river valleys and low lying areas.
- Extended period of dry conditions and above normal
  temperatures expected today through early October, with
  comfortable humidity.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 233 AM CDT Thu Sep 25 2025
Early morning surface analysis shows a large area of high
pressure across the central CONUS stretching from the southern
Plains to the upper Midwest. Aloft, an upper low was seen
rotating over the Great Lakes centered over northwest MI. Closer
to home, a small area of stratus was forming in north central IL
with the rest of the area under clear skies per GOES 19
Nighttime Microphysics channel.
Today...with dewpoint depressions already near zero in some
areas, patchy fog will be possible prior to sunrise especially
in river valleys and low lying areas. Any fog, will quickly burn
off after 9 am. Otherwise, another pleasant day is in store
with mostly sunny skies and light winds. Forecast soundings show
similar mixing depths to what occurred yesterday so highs
should be close to readings yesterday, with values reaching the
upper 70s.
Tonight...a weak wave to drop south out of MN and may bring an
increase in high clouds. Otherwise, quiet and dry conditions
will be seen with lows dropping into the lower 50s.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 233 AM CDT Thu Sep 25 2025
Friday-Saturday Night...blocking pattern aloft to bring warm
and dry conditions with large diurnal temperature swings. Above
normal highs in the low to mid 80s and lows in the low 50s will
make for beautiful weather for any outdoor plans.
Early Next Week...all deterministic and ensemble model
solutions continue to show a building upper level ridge
overhead bringing above normal temperatures and continued dry
conditions. Both the NAEFS and ENS ensemble tables show this
500mb ridge to be near or at the highest end of climatology for
the Midwest, resulting in high confidence warmth and dry weather
for the rest of September. If we don`t receive any more rain at
MLI, we would have seen the 6th driest September on record with
only 0.71" rain. Taking a look at temperatures, widespread highs
in the middle 80s will be possible especially on Monday. The
NBM distribution for MLI now has 59% of members with highs that
are 84 degrees or higher. For those wanting summer warmth but
without the oppressive humidity, then next week will be your
ideal weather.
&&
.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 621 AM CDT Thu Sep 25 2025
Some MVFR fog is possible early this morning, mainly for our
northern TAF terminals. Otherwise, VFR conditions will prevail
through the period with light north-northwest winds. Daytime
cumulus clouds will also be common this afternoon.
&&
.CLIMATE...
Issued at 233 AM CDT Thu Sep 25 2025
The latest 8-14 day temperature outlook from the Climate
Prediction Center shows very high probabilities (70%) of above
normal temperatures for the Oct 2nd to Oct 8th timeframe. Normal
highs for this period are in the upper 60s/lower 70s and normal
lows are in the mid to upper 40s. While above normal
temperatures are likely, the humidity levels will be tolerable.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...None.
IL...None.
MO...None.
&&
$$
SHORT TERM...Gross
LONG TERM...Gross
AVIATION...Schultz
CLIMATE...Gross

NWS DVN Office Area Forecast Discussion