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fxus63 kilx 060231 
afdilx

Area forecast discussion
National Weather Service Lincoln Illinois
831 PM CST Thu Dec 5 2019

Synopsis...
issued at 300 PM CST Thu Dec 5 2019

Clouds will be on the increase across central Illinois tonight as
a weak disturbance passes well south of the region. A few light
rain showers may develop as far north as the I-70 corridor late
tonight into Friday morning...with dry weather expected to
persist further north.

&&

Update...
issued at 828 PM CST Thu Dec 5 2019

Cloud cover has rapidly expanded across central Illinois this
evening resulting in overcast conditions for most of the area.
Have slowed temps falling this evening with faster arrival of
clouds and bumped up overnight lows a bit, mainly across the
northern half of the County Warning Area. Meanwhile, showers have developed over
southeast MO and far southern Illinois this evening. Short term guidance
does suggest this may expand north into portions of central
Illinois overnight, however, 00z kilx raob indicate a deep low
level dry layer which will be tough to overcome. Have kept pops
mainly along and south of I-70 despite some models bringing precip
further north. Think if any precip does develop further north it'd
only be a sprinkle.

&&

Short term...(this evening through friday)
issued at 300 PM CST Thu Dec 5 2019

A cold front currently extending from Minnesota to the Texas
Panhandle will push eastward over the next 24 hours...bringing
clouds and cooler weather to central Illinois. A vigorous short-
wave trough noted on 20z/2pm water vapor imagery over eastern
Colorado will interact with the boundary to produce light rain
from the Ozarks northeastward into the Ohio River valley late
tonight into Friday morning. Model solutions have all trended
further south with the precip, with consensus confining the
showers to locations along/south of I-70. Even where precip occurs
across the southeast kilx cwa, total rainfall will only amount to less
than one tenth of an inch. The cold front will cross the
Mississippi River by midnight...then will drop south of I-70 by
midday Friday. Once it departs, skies will rapidly clear from
northwest to southeast...with abundant sunshine expected across
most of central Illinois by Friday afternoon. Temperatures will be
several degrees cooler than today, mainly in the lower to middle
40s. In addition, brisk north/NE winds gusting to around 20mph will
make it feel even cooler.

Long term...(friday night through thursday)
issued at 300 PM CST Thu Dec 5 2019

High pressure will settle into the region Friday night, bringing
clear skies and very light winds. Thanks to nearly ideal
radiational cooling conditions, overnight lows will dip into the
lower to middle 20s. As the high departs and southerly boundary
layer flow resumes, a warming trend will get underway over the
weekend. Highs on Saturday will remain in the 40s, but will
rebound into the lower to middle 50s by Sunday.

As has been well-advertised for the past several model runs, a
significant trough will dig into the Midwest/Great Lakes early
next week bringing a winter-like airmass into central Illinois.
Rain will develop in advance of the system Sunday night into
Monday, then will gradually change to snow before coming to an end
Monday night. Given the forward speed of this feature and the fact
that the cold air will lag behind the trailing cold front, think
any snow accumulations will be minimal. The main weather story
will be the windy and sharply colder conditions noted on Tuesday
when afternoon high temperatures only reach the upper 20s and
lower 30s. As lows plunge into the single digits and teens,
corresponding wind-chill values will drop to near zero by Tuesday
night. After that, chilly conditions will persist through Thursday
before the upper trough lifts into New England and a zonal flow
pattern tries to re-establish by the end of next week.

&&

Aviation...(for the 00z tafs through 00z Friday evening)
issued at 513 PM CST Thu Dec 5 2019

South winds and VFR conditions are in place ahead of an
approaching cold front. Winds will veer to the south-southwest/SW ahead of the
front with increasing mid and high clouds this evening. Overnight,
winds will veer to the northwest then north as the front passes through
the terminals. A few hours of MVFR ceilings may develop in the
wake of the front, but should scatter/clear out during the day
Friday. North winds will be gusty behind the front, into the low
to mid 20 kt range, then should gradually ease through the day.



&&

Ilx watches/warnings/advisories...
none.
&&

$$

Update...deubelbeiss

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