903
FXUS63 KILX 270544
AFDILX

Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
1244 AM CDT Thu Mar 27 2025

.KEY MESSAGES...

- Periods of showers are expected through Thursday, with thunder
  chances arriving Thursday evening. Any strong to severe storm
  chances in this time frame appear to be during the evening
  hours, with an elevated hail threat.

- Better severe weather chances look to be Sunday afternoon,
  though trends have been to refine the threat more near and south
  of I-70.

- Friday will be the warmest day of the upcoming 7-day period,
  with highs getting close to 80 degrees in many area.s

&&

.DISCUSSION...
Issued at 244 PM CDT Wed Mar 26 2025

Lingering showers moved out of southeast Illinois by mid morning
today, and while clearing took place for awhile, plenty of fair-
weather cumulus has developed over central Illinois. GOES channel
7 imagery has shown a number of hot spots over the last several
hours, from numerous controlled burns, with smoke plumes also
appearing on radar.

Through Thursday Night:

High pressure will slowly drift across the region this evening,
before scattered showers begin to develop after midnight in an
area of warm air advection to our southwest. Main focus looks to
be from northern Missouri into south central Illinois overnight,
though a few of the high-res models suggest some activity by early
morning closer to I-74. Most widespread activity should be
Thursday morning, then diminishing for a time from the northwest.
Thunder chances during this period appear low, though training
echoes suggest some potential for streaks of heavier rain
accumulations. SPC Day2 outlook maintains a level 1 (marginal)
risk of severe weather. This appears more likely during the
evening, as the warm front lifts north and elevated storms take
advantage of MUCAPE values near 1000 J/kg to produce some isolated
large hail. Rain chances diminish from south to north overnight as
the warm front lifts north of the area.

Friday through Sunday:

Friday still is slated to be the warmest day of the forecast
period, with high temperatures in the upper 70s to around 80. Rain
chances begin to return late Friday night as a plume of Gulf
moisture is drawn northward with a shortwave moving across the
lower Mississippi Valley. NBM PoP`s appear to be a bit aggressive
with Saturday morning rain chances over central parts of Illinois,
perhaps tied more toward the further south position of the warm
front to our north (near I-80 vs. central Wisconsin as shown by
the international models). With that more southern position, the
GFS is also a little faster and stronger with the late weekend
storm system, suggesting there could be more of a dry slot Friday
night. In terms of the Sunday severe weather threat, recent
SPC outlooks have been trending a bit further south, with morning
guidance model guidance suggesting more of an area near/south of
I-70 being the greater threat.

Monday through Wednesday:

Recent runs of the European model have been developing another
storm system over the central Plains on Tuesday, moving into the
Midwest on Wednesday. Only a few of the GFS ensembles are
suggesting such a solution, with the positioning highly variable.
The various machine learning guidance is keeping the severe threat
to our south during this period, but it would be worth watching
this time frame as models begin to resolve this system. In the
meantime, the new work week starts off on the cool side, but
trends back to a milder weather pattern by mid week.

Geelhart

&&

.AVIATION...  (For the 06z TAFs through 06z Thursday Night)
Issued at 1219 AM CDT Thu Mar 27 2025

VFR conditions to persist into Thursday morning amid increasing
mid-level clouds. Periods of MVFR ceilings will overspread all
central Illinois terminals between 18z-00z as a surface warm front
lifts across the area, providing occasional rain showers. Surface
winds will also become predominately southeasterly during this
time, increasing to about 10 kts with peak afternoon gusts around
20 kts. Then, after a brief period in which VFR conditions return
Thursday evening, additional scattered showers and thunderstorms
will develop late in the TAF period. Confidence and coverage of
thunderstorms at any one terminal remains uncertain, and so we have
handled this potential with a PROB30 group.

MJA

&&

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

$$