Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 211731
AFDILX

Area Forecast Discussion
National Weather Service Lincoln IL
1231 PM CDT Mon Apr 21 2014

.DISCUSSION...
ISSUED 1037 AM CDT Mon Apr 21 2014
Cold front still to the NW and showers moving in ahead of the cold
air this morning. SW starting to see some brief showers...and
expect to spread through the afternoon. For now, isolated thunder
in southern WI. However, the showery nature of the rainfall allows
for some breaks in the clouds and diurnal heating to kick in.
Pockets of sunshine will contribute to some increased instability
as the day progresses. Still some dry air to work through out
there as the leading edge of the approaching precip still getting
eroded in the eastern half of the CONUS. Made some minor
adjustments to the morning pops...and the high temps as
well...dropping them just a bit as clouds and showers move in and
limit the overall temp rise. That being said...anyone that gets a
little bit of sunshine will likely be a couple degrees warmer.



&&

.AVIATION...
ISSUED 1224 PM CDT Mon Apr 21 2014
Majority of rainfall is from VFR cigs, with a +RA and reduced vis
from heaviest shower from SPI to BMI to briefly IFR. SHRA through the
afternoon with VCTS possible. Current lightning mostly confined to
the north and northwest near the front and better dynamics. Best
chance for iso ts is later this afternoon, but keeping with the
vcts for now as sunshine starting contribute to pockets of
increased instability. Cooling tops on sat imagery showing
increased vertical development. SW to W flow ahead of
boundary...switching around to NW behind fropa from 04z-07z. An
additional concern is the development of some MVFR cigs behind the
boundary...but will keep out of the fcst for now to see if the
cloud deck fills in and persists.


HJS
&&

.PREV DISCUSSION...
ISSUED 330 AM CDT Mon Apr 21 2014

SHORT TERM...Today through Thursday night

00Z models in fair agreement next few days and have trended quicker
with moving cold front east of IL by overnight Thu night. Have
therefore lowered pops overnight Thu night.

First wx system to affect IL today and tonight is 1009 mb low
pressure just north of nw MN with its cold front into eastern NE
and central KS. Scattered showers and thunderstorms ahead of this
system over IA and western MO to spread east across IL during the
day and mainly holding off until the afternoon especially eastern IL.
Another mild day in the mid to upper 70s with mildest readings
over eastern IL as skies become mostly cloudy to overcast. Cold
front to sweep east across IL this evening with showers likely
along with a few thunderstorms this afternoon/evening. Rain
chances diminish by overnight and mainly east of I-57 early overnight
as skies clear from west to east overnight behind cold front. Lows
tonight range from mid 40s nw of IL river to near 55F se along the
Wabash river by Lawrenceville.

Weak high pressure ridge settles into IL by Tue evening and brings
fair skies Tue and Tue night along with cooler temps. Highs in the
low to mid 60s Tue/Wed with upper 60s se IL and sw areas. Lows
tonight 35 to 40 and could be some patchy frost over east central
IL where lows get in the mid 30s overnight Tue night with clear
skies and light winds.

A stronger storm system near the west coast to bring isolated waa
convection nw of IL river Wed and Wed night though better chances
with warm front to be further north of our CWA. Models consistent
is showing strong low pressure passing north of IL Thu/Thu night
though timing differences yet with passage of cold front, either
Thu afternoon or Thu evening. Likely chances of showers and
thunderstorms Thu and lingering over Thu evening especially
eastern IL. Will need to watch potential for strong to severe
storms Thu afternoon/evening.

LONG TERM...Friday through Monday

Dry conditions return Friday as models have shifted the wrap
around moisture further north by low pressure over WI/MI. So
removed the slight chance of rain showers ne counties Friday
with partly to mostly sunny skies. Highs Fri to range from the
mid 60s north of Peoria to the mid 70s se of I-70. Dry conditions
prevail Friday night and most of Saturday as clouds increase by
Sat. Highs Sat in the upper 50s from I-74 north to mid 60s se of
I-70. GFS is trending further south with next storm system early
next week and keeping central IL mostly dry Sun/Mon. ECMWF is more
aggressive in bringing moisture ne into central/se IL by early
next week. Will continue chance pops of showers and isolated
thunderstorms from Sat night through Monday. Highs Sunday similar
to Sat highs while a bit cooler Monday with highs 55-60F.

07


&&

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

$$







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