387 
FXUS63 KILX 021714
AFDILX

Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
1214 PM CDT Sat Aug 2 2025

.KEY MESSAGES...

- Smoke from wildfires will persist over central Illinois today,
  though the greatest concentrations will remain aloft. At the
  surface moderate air pollution is expected, though is an
  improvement from yesterday.

- Comfortable humidity levels will be in place through the weekend
  along with below normal temperatures. Any precip should hold off
  until next week.

&&

.DISCUSSION...
Issued at 158 AM CDT Sat Aug 2 2025

High pressure will persist over the Great Lakes region through 
the weekend, leading to significantly lower humidity levels and 
below-normal temperatures across central Illinois. Northeast 
winds, gusting to around 15 mph, are anticipated from late morning
through this evening and will continue to advect 50-degree dew 
points into the region, reinforced by deep mixing. This low-level 
northeast flow will help maintain temperatures below the normal 
high of 85-86 degrees. Highs are expected to be in the upper 70s 
to around 80 today and will warm by another degree or two on 
Sunday.

In addition, wildfire activity upstream will continue to advect 
smoky and hazy conditions into the region, though impacts will be 
mainly aloft today. Regional observations indicate that the 
earlier reported reduced surface visibility across the region has 
generally improved with most sites now above 6SM visibility 
overnight. Near-surface smoke is projected by the HRRR/RAP to be 
in much lower concentrations across central Illinois today. EPA 
projections still show moderate air quality pollution, but this 
remains an improvement from the unhealthy quality yesterday. 
Aloft, westerly flow will advect in additional high-level smoke 
through the remainder of the weekend.

The surface ridge axis will gradually shift eastward through the 
upcoming week, causing surface winds across central Illinois to 
veer southeasterly. While not the most efficient return flow, dew 
points are expected to gradually increase, reaching the 60s early 
in the week and eventually the 70s by midweek. A blocky upper 
ridge will be present over the southwest CONUS for much of next 
week, positioning central Illinois near an area of split flow 
downstream. Consequently, significant forcing areas are absent, 
with the main storm track and jet stream retreating well 
northward. Precipitation chances will be largely confined to 
isolated to widely scattered afternoon/evening convective activity
due to the lack of notable synoptic forcing.

Deubelbeiss

&&

.AVIATION...  (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1214 PM CDT Sat Aug 2 2025

The circulation around high pressure centered over WI today 
continues bring light northeasterly breezes to the central IL
terminals, as well as re-circulate smoke over the region. Surface
observations continue to suggest VFR visibilities continuing for
the upcoming 24 hours, however periods of MVFR cannot be ruled out
and will need to be watched for.

37

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$