130
FXUS63 KILX 082315
AFDILX

Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
615 PM CDT Fri Aug 8 2025

.KEY MESSAGES...

- Seasonably warm and humid conditions will prevail on Saturday,
  with a heat index of 100-105 degrees likely west of I-55.

- A significant threat of flooding will set up over parts of the
  Midwest this weekend, though it is likely to be focused just to
  our northwest. Concerns for any potential flooding in our area
  would be highest near Galesburg.

&&

.SHORT TERM...  (Through Late Saturday Afternoon)
Issued at 230 PM CDT Fri Aug 8 2025

Fairly quiet across the forecast area this afternoon, with
seasonably warm and humid conditions. Our area is currently
influenced by a ridge of high pressure aloft extending out of the
Desert Southwest, and that will continue into Saturday. With
tomorrow`s temperatures and dew points fairly similar to today,
potential for heat index values to be above 100 degrees are
highest northwest of the Illinois River. However, confidence in
reaching advisory level (105) is not high enough to pull the
trigger quite yet.

.LONG TERM...  (Saturday Night through Next Friday)
Issued at 230 PM CDT Fri Aug 8 2025

Main concern during this period is thunderstorm potential and
associated heavy rainfall.

Water vapor imagery shows a well formed upper low spinning over
northeast Montana and southern Saskatchewan this afternoon. Global
models show an elongating trough south of it through the weekend,
helping to sharpen the ridge as shifts more toward the eastern
Great Lakes. HREF precipitable water values ramp up to around 2
inches or so from western Missouri into southern Wisconsin by late
Saturday afternoon. A corridor of heavy rain is likely to set up
in this region Saturday night, as an incoming cold front runs into
the ridge and stalls out. Latest WPC Day2 and Day3 excessive
rainfall outlooks introduced a moderate risk in this area, but
staying just off to our northwest (near the IA/IL border).
However, WPC rainfall guidance suggests 3-4 inch potential in the
far northwest CWA near Galesburg, while the NBM is a little tamer
at 1.5-2 inches. Most of the high-res guidance is suggesting any
such flooding issues in our area would be after midnight Saturday
night, with another MCS also developing Sunday night. Will need to
watch this area for potential flood headlines. Severe-wise, with
the storm timing pretty late in the night, the severe threat is
not especially high, but a few stronger wind gusts can`t be ruled
out late Saturday night.

With the areas southeast of I-55 more under the influence of the
ridge, rain chances will be fairly minimal through the weekend.
The upper trough over the Plains starts making some slow eastward
progress early next week, but with the main focus remaining west
of I-55, any convection further southeast will likely be more of
the pop-up variety until around Tuesday.

In the longer range, global models show the next trough starting
to dig south along the West Coast late in the week. This would
amplify the upper ridge across the Plains once again, with a
gradual warming trend developing late week. Long range ensembles
suggest this would continue into the following week as well, with
CPC 8-14 day outlook featuring 60-70% chance of above normal
temperatures for August 16-22.

Geelhart

&&

.AVIATION...  (For the 00z TAFs through 00z Saturday Evening)
Issued at 615 PM CDT Fri Aug 8 2025

VFR conditions will prevail at all sites next 24hrs. This evening
and overnight, skies will just have few cirrus. Tomorrow, late
morning, a few CU will develop again with scattered cirrus. Winds
will be south tonight with speeds around 10kts. South winds again
tomorrow with gusts to a little over 20kts...similar to today.

Auten

&&

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

$$