213
FXUS63 KILX 270737
AFDILX

Area Forecast Discussion
National Weather Service Lincoln IL
237 AM CDT Mon May 27 2024

.KEY MESSAGES...

- Scattered thunderstorms (20-30% chance) will pose a threat of
  gusty winds this afternoon into the evening, primarily between 4
  PM and 9 PM. There is a level 1 of 5 risk of damaging winds.

- Tuesday afternoon/evening will also feature scattered storms
  capable of gusty winds (20% chance), mainly north of I-74.

- High pressure takes control for the latter half of the week,
  with dry weather Wednesday through Friday.

&&

.SHORT TERM...  (Through Late Tonight)
Issued at 237 AM CDT Mon May 27 2024

Early Monday morning, sfc low pressure was positioned over the
Great Lakes region, with an attendant cold front extending
through north- central IN into east-central IL. As of 2am/07z the
front had moved past a Danville to Taylorville line, but had not
yet reached Paris- to-Effingham. A few spotty showers have
developed near and just ahead of the front, so kept some low
chance PoPs during the first few hours of the forecast period.
These showers should be east of the area by daybreak today.

Today, central IL will be in the post-frontal airmass, which will
feature persistent northwest winds gusting 20-30 mph. A digging
shortwave will approach from the northwest by mid-afternoon,
leading to scattered showers/storms. Instability progs are rather
weak, less than 750 J/kg, but forecast soundings have consistently
shown a deep- inverted V profile beneath the cloud bases, which
are expected to be over 4000 feet. Efficient evaporative cooling
beneath these cloud bases could lead to sporadic strong downdrafts
capable of producing strong wind gusts. This assessment is
supported by high- res guidance, as the 27.00z HREF indicates a
20-40% chance of gusts over 45 mph with these storms. There is a
marginal risk (level 1 of 5) for damaging winds. Other severe
hazards (hail, tornadoes) are not expected.

Radar estimates suggest that nearly all of the CWA has received
at least a half inch of rain since Friday, and a majority of the
CWA has received over 1". That will hopefully stymie any blowing
dust concerns with these gusty thunderstorms.

Erwin

.LONG TERM...  (Tuesday through Sunday)
Issued at 237 AM CDT Mon May 27 2024

Tuesday looks fairly similar to Monday, with continued cyclonic
(northwesterly) flow and another shortwave approaching during the
afternoon which could kick off more showers/storms, mainly north
of I-74 (20% chance). Forecast soundings for Tuesday show similar
signatures to Monday, so gusty winds will once again be possible
with any storms that form.

Conditions are looking quite enjoyable Wed thru Fri as upper level
ridging set up over the central Plains, resulting in
strengthening, broad sfc high pressure over the Upper
Midwest/Ontario. These features will gradually shift east during
the latter half of the week, but will provide mostly dry weather
Wednesday-Friday while temperatures steadily warm each day. By
Fri, highs return to near normal, around 80F. Dewpoints in the
upper 40s/low 50s will make it feel quite refreshing.

Into the weekend, the upper ridge shifts east while a trough
approaches from the west, returning precip to the forecast Sat-
Sun. Early indications are that the severe weather potential with
this system is quite low, owing to limited moisture return.

Erwin

&&

.AVIATION...  (For the 06z TAFs through 06z Monday Night)
Issued at 1158 PM CDT Sun May 26 2024

A cold front will continue to push through the central IL
terminals for the first few hours of the forecast period, with
little or no chance for any precipitation developing along the
front at this point. However, an area of MVFR cigs is poised just
upstream, and is expected to move over most of the area overnight.
Lifting and dissipation of this cloud cover should result in VFR
conditions by 13Z-16Z. Another shortwave will arrive in the
afternoon, resulting in widely scattered showers and thunderstorms
mainly near and north of the I-74 corridor until around 04Z. Winds
NW around 10 by 06Z-11Z, increasing to 12-16 kts with gusts 20-25
kts by 16Z. Winds decreasing after 01Z.

37

&&

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

$$