FXUS63 KILX 170128
AFDILX

Area Forecast Discussion...Updated
National Weather Service Lincoln IL
828 PM CDT Fri May 16 2025

.KEY MESSAGES...

- After the recent severe weather and dust storm, the weekend
  looks much tamer.

- Gusty winds will continue into Saturday, especially north of
  I-72/Danville.

- An extended period of high rain chances is expected Monday
  through Wednesday, though severe weather potential is highly
  uncertain at this time.

&&

.UPDATE...
Issued at 828 PM CDT Fri May 16 2025

The severe weather has pushed well to our east and south with the
arrival of sunset, and the unusual dust storm that impacted parts
of the area lifted northeast out of the area a couple hours ago.
Still seeing some stronger wind gusts, especially near the I-74
corridor, though they have shifted to the west. Will keep the Wind
Advisory going across the northern CWA for now, with the HRRR
suggesting some gusts near 40 mph will continue the rest of the
evening.

Main forecast updates were to remove the remaining rain chances
for this evening, as well as update the dew point grids and sky
trends.

Geelhart

&&

.DISCUSSION...
Issued at 143 PM CDT Fri May 16 2025

A mid level disturbance lifting northeast out of the central Plains
will bring an opportunity for severe thunderstorms to the region
this afternoon and evening. In its wake, conditions turn dry and
cooler for the upcoming weekend. Early next work week, thunderstorm
chances will return with the approach of another trough lifting out
of the Great Plains.

***** SEVERE WEATHER RISK THIS AFTERNOON-EVENING *****

At 2pm, surface temperatures were in the mid to upper 80s across
central IL, with dewpoints ranging from the low to mid 60s south
of roughly I-70 to low 40s west of the IL River. The more abundant
moisture continues to surge north in advance of a mid-upper level
disturbance lifting towards the region from the Central Plains,
though this will eventually be limited by ongoing upstream
convection across east-central MO. As these storms build
northeast along the dryline and move into central IL, they will
pose a risk for all severe hazards, including large-significant
hail, destructive downburst winds; meanwhile, the risk for
tornadoes will be higher in southeast and east-central IL where
low level moisture is higher and hence LCL heights are lower.
While convective mode is depicted in virtually every CAM as
discrete to start, there may be a tendency towards upscale growth
into a MCS capable of widespread damaging winds. Fortunately,
these storms will be moving quickly, so the threat will be
rapidly diminishing from west to east and we'll update the watch
accordingly. By 9pm (if not sooner), the storms should be out of
here.

***** GUSTY WINDS TODAY ****

South-southwest winds will continue to gust 30 to 40 mph today, with
some potential for sporadic gusts up to 50 mph especially across
our western counties where winds aloft will be increasing with the
approaching upper level trough. HRRR/RAP Bufkit soundings suggest
top of channel winds could exceed 50 kt at times mainly west of
the IL River, but we suspect a slight dry bias may be resulting in
erroneously high values; nonetheless, we'll be monitoring surface
observations in case we need to expand the Wind Advisory to
include more counties. In addition, these strong winds could
result in some localized blowing dust which could degrade
visibility for motorists, especially considering we already had a
few reports of such blowing dust yesterday and winds are running
slightly stronger today. These strong winds, combined with dry low
levels (RH values < 30%) across our north/northwest counties, are
resulting in increased fire weather danger which will continue
through the evening. See the fire weather section below for more
information on that.

***** DRY AND COOLER THIS WEEKEND *****

The upper trough will shift east and surface high pressure build
into the region in its wake tomorrow/night, giving us a dry and
seasonably cool weekend with daily highs in the low to mid 70s.
Tomorrow may actually feel a bit chilly given northwest winds
gusting to around 30 mph. The next opportunity for precipitation
will arrive Sunday night/Monday into Tuesday of next week as another
system lifts out of the Central Plains. A lot remains unclear about
that system, including its arrival time and warmth/moisture return
ahead of it, which suggests vast uncertainty surrounding both
precipitation amounts and any severe weather potential. However, a
strong push of cool advection appears increasingly likely towards
the middle of next work week; blended guidance from NBM brings highs
into only the low to mid 60s by Wednesday.

Bumgardner

&&

.AVIATION...0Z TAFS THROUGH 00Z SUNDAY/...
Issued at 632 PM CDT Fri May 16 2025

Line of strong to severe storms east of I-55 along the I-70
corridor will continue to move east, exiting the forecast area
by 1z. Otherwise, mostly VFR conditions are expected the period,
with some morning low VFR to MVFR stratus.

Strengthening LLJ may lead to some LLWS this evening into
tonight, especially for the I-55 and I-72 corridors, so have
added mention to KBMI/KSPI/KDEC. Westerly winds remain strong to
breezy through the forecast period, with gusts 20 to 30 knots.

SG

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 11 PM CDT this evening for ILZ027>031-037-
038.

&&

$$