804 
FXUS63 KILX 242325
AFDILX

Area Forecast Discussion
National Weather Service Lincoln IL
625 PM CDT Mon Jun 24 2019

.SHORT TERM...(This evening through Tuesday night)
ISSUED AT 250 PM CDT Mon Jun 24 2019

Latest surface map shows the cold front is near the Illinois/Iowa
border southwest into central Missouri. Earlier cloud deck is well
to our east, and we're more in a diurnal type pattern. Scattered
thunderstorms have been developing ahead of the front, where
CAPE's are 1500-2000 J/kg. Bulk shear remains quite minimal,
though, so any stronger storms are likely to be more of the
pulse-type. Bulk of the rain should be east of the forecast area
by early evening, though with the front near I-57 by 7 pm, some
lower PoP's will be kept in that area until near sunset.

Next focus is on Tuesday afternoon and evening, involving the
shortwave currently moving into western North Dakota. Made some 
significant changes to the PoP's late afternoon into the evening,
going with 60% PoP's across the far northwest by evening. Latest
SPC Day2 outlook greatly expanded the slight risk, which is now
over the northwest 2/3 of the CWA. Latest NAM and GFS bring 
CAPE's over 3000 J/kg west of the Illinois River by late 
afternoon. A number of the high-res models focus more on a line of
storms forming in southern Iowa and dropping through western 
Illinois, with a separate segment closer to Lake Michigan. With
shear again nothing to write home about, not expecting a large
outbreak, but potential for stronger wind gusts and hail is there. 

.LONG TERM...(Wednesday through Monday)
ISSUED AT 250 PM CDT Mon Jun 24 2019

Longer range continues to show a very warm and humid pattern into
next weekend, as upper level ridging amplifies over the Plains.
850 mb temperatures rise to around 19C by Friday, and rise a 
little more through the weekend. High temperatures will gradually
creep upward and will be near 90 by the weekend, with peak heat
index values in the mid 90s.

This sort of a pattern will keep rain chances lower. The main
concern is with a shortwave riding over top of the ridge Thursday
night and Friday. GFS is quite generous with the rain amounts all
the way down to the Ohio Valley, while the European and Canadian 
models keep the activity to our north. Think the drier solution is
more reasonable. A stray storm can't be ruled out, but will only
mention silent 20 PoP's across the northern CWA for now. Other
thunderstorm activity across the region will be more in the form
of ridge-riding MCS complexes, with the Great Lakes region more
likely to be the recipients. 

&&

.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 624 PM CDT Mon Jun 24 2019

A cold front has already progressed past all of the TAF sites, as
evidenced by their gusty west winds at 14G24KT. Drier air will
filter into the area, helping to diminish most of the remaining
clouds. There will be a rapid decrease in winds as sunset
approaches, and decoupling takes place in the boundary layer.
Advancing high pressure will provide VFR conditions for a majority
of the day on Tuesday. However, gusty southwest winds will develop
by mid-day. The late afternoon storms that are expected to roll 
out of Iowa into our NW counties could affect PIA very late in 
this TAF period. MVFR conditions would be likely at PIA if that
occurs. Better chances of storms will come early Tue evening for
the TAF sites.

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Geelhart
LONG TERM...Geelhart
AVIATION...Shimon