Area Forecast Discussion
Issued by NWS Central Illinois

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS63 KILX 270930

National Weather Service Lincoln IL
330 AM CST FRI NOV 27 2015

.SHORT TERM...(Today)

A cold front currently located from near Springfield to Bloomington
will continue to progress eastward today...reaching Lawrenceville
around 6 p.m. Behind the front...a rapid change from south winds 15-
20 mph to north winds around 15 mph with gusts 20-25 mph will take
place. Mild temperatures in the upper 50s and low 60s ahead of the
front will drop off rapidly into the 40s and even some upper 30s
from around the Illinois River northwest. Many locations will see
cooler temperatures in the afternoon than the morning as a result. A
band of widespread rain and scattered heavier showers ahead of and
behind the front should result in rainfall amounts of around an inch
most areas through 6 p.m. today. By 6 a.m...most of the heavier
rainfall will already be concentrated along and east of the I-55
corridor where a plume of 1 to 1.25 inch precipitable water will
continue. Cooler air will gradually settle in from the north behind
the boundary...which will remain fairly saturated but not as rich in
moisture as regions ahead of the front. Although heavier showers
will produce some local visibility issues for travelers...any frozen
precipitation will be absent through the daytime today for central


.LONG TERM...(Tonight through Thursday)

November will end on a wet note across central and southeast IL
as split upper level flow to continue across the country into early
next week with two upper level waves to affect our area. A cold
front near the Wabash river at 00Z/6 pm today will continue to
slowly press southeast toward the Ohio river tonight and likely
continue rain chances behind the front tonight though diminishing nw
of the IL river. and stay close to there this weekend as a series of
surface low pressure waves lift ne along it. Meanwhile 1041 mb
Canadian high pressure over the Dakotas will ridge eastward into the
upper Great Lakes regions this weekend. This will try to bring drier
weather to areas from Peoria northward Sat and Sat night while rain
chances continue over central and especially southeast IL where
heavier rains will be.

Very high precipitable water values are 1-1.5 inches through
Saturday and highest in southeast IL, and even surpass 1 inch in
southern areas into Monday. Also will be getting some moisture from
Hurricane Sandra near the west coast of Mexico this weekend.
Rainfall amounts will be as much as 1.5-2.5 inches se of I-55 while
much lighter amounts over the IL river valley where most of rain
there will occur today. Flash Flood guidance values are 1.5-2 inches
per hour, 2-3 inches in 3 hours and 3-5 inches in 6-12 hours. So
well below these values and will not issue a flood watch. But some
rivers and streams in southeast IL like the Little Wabash river at
Clay City will likely go above flood stage this weekend.

Lows tonight to range from the lower 30s nw of the IL river, to the
lower 40s in southeast IL southeast of I-70. Cooler highs Sat in the
lower 40s central IL and mid 40s southeast IL. Just a few degrees
higher on Sunday in the mid 40s central IL and upper 40s southeast
IL. 00Z models are lifting moisture back north into central IL
during Sunday night and Monday as strong cutoff 500 mb low 548 dm
over NV ejects into the central plains Monday with surface low
pressure deepening and tracking ne into the upper MS river valley by
Tue morning. This system appears to bring mostly rain to the area
from Sunday night through Monday night and then diminishing from the
sw on Tue. Did continue a chance of mix precipitation over the IL
river valley overnight Monday night into Tue but qpf amounts are
fairly light then so not expecting much accumulation if snow does
occur. Brunt of precipitation shifts ne of central IL Tue night and
dry on Wed as storm system pulls away and high pressure drifts east
into the central plains by mid week. Seasonably cool temperatures to
prevail during much of next week with highs mostly in the 40s and
lows in the upper 20s and lower 30s from Tue night on.


.AVIATION...(For the 06Z TAFS through 06Z Friday night)

A slow moving frontal boundary will gradually shift across the
central Illinois terminal area tonight, likely clearing KCMI by
shortly after sunrise. VFR and mostly rain free condtions prevail
ahead of the front, with conditions rapidly falling to IFR with
widespread rain as the front passes by. The low CIGS/VSBYs &
rainfall or drizzle, once they arrive, should linger for the
balance of the 06Z TAF valid time. The wind shift with FROPA
should be significant, changing from almost due south to due


.ILX Watches/Warnings/Advisories...


AVIATION...BAK is the U.S. government's official web portal to all federal, state and local government web resources and services.