Area Forecast Discussion
Issued by NWS Central Illinois

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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

000
FXUS63 KILX 291935
AFDILX

Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
235 PM CDT Wed Oct 29 2014

.SHORT TERM...(Tonight)
ISSUED AT 234 PM CDT WED OCT 29 2014

Surface high continues to build into the region this evening.
Despite the quiet weather, a wave moving into the upper trof will
usher some moisture into ILX in the form of clouds.  Time heights
showing arrival of cirrus and a slow transition to more mid clouds
as the early morning hours progress.  Light and variable winds will
assist in efficient radiational  cooling under the clearer skies.
Frost threat is better in the eastern half of the state under the
ridge axis in the early morning hours. The winds slowly pick up a
more southerly component a few hours before dawn in the western
half, pushing slightly warmer air into the area and keeping the
temps from bottoming out.


&&

.LONG TERM...(Thursday through Wednesday)
ISSUED AT 234 PM CDT WED OCT 29 2014

An extended period of below normal temperatures is on tap across
central and southeast Illinois for the next several days. The
coldest period will extend from Friday to Sunday, with a hard freeze
likely early Saturday and Sunday mornings. Do not plan to go with a
Freeze Watch at this time since the freezing conditions are more
than 48 hours out in time, but will continue to highlight the risk
in the Hazardous Weather Outlook and Weather Story Graphics. While
this will be the first hard freeze across the forecast area, it is
"normal" (or late in many areas) for a first freeze to occur in late
October. Halloween Trick or Treat conditions will be less than ideal
with actual temperatures in the upper 30s or lower 40s and Wind
Chill values around 30 degrees.

Other than the chilly temperatures, the main forecast concerns
revolve around rainfall chances tomorrow with a weak wave, as well
as with a stronger system for the beginning of the next work week.
For tomorrow, a short wave, currently digging southeast out of the
northern Rockies, is progged to pass just southwest of the forecast
area. A quick shot of WAA/isentropic ascent ahead of the wave,
mainly Thursday afternoon/early evening, should be able to squeeze
out some light showers. However, the rainfall is not expected to be
significant. A much stronger wave, currently diving into
Saskatchewan and Manitoba, will track across the Great Lakes/Midwest
on Friday. While this system is potent, it will be moisture starved,
with most of the associated precipitation expected to fall
north/east of the forecast area as it passes through. However, this
system will be accompanied by gusty winds and will help usher in the
airmass that will provide our hard freeze for the weekend.

Upper level ridging will begin to build into the area by late in the
weekend into early next week. The ridge will break down by later
Monday into Tuesday as a strong disturbance of Pacific origin pushes
east toward the area. The frontal system driven by this wave will be
accompanied by showers. The risk of showers may be prolonged since
the front will become nearly parallel to the upper level flow and be
a slow mover. However, the model guidance is still not in good
agreement (or with great run-to-run consistency) regarding how quick
the front will ultimately be. So, how long the rainfall risk will
linger beyond Tuesday is still subject to debate.


&&

.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
ISSUED AT 102 PM CDT WED OCT 29 2014

VFR through the overnight. Some diurnal element to the clouds over
the north and central portions of the state. Even though some
clearing is expected tonight around sunset, more clouds will
continue to build into the region from the north. Cirrus after
midnight, spreading southward into the early morning hours. Time
heights showing a drop of the cigs steadily from 12z on...to more
of a low deck by mid day at the latest for all ILX terminals.
Starting the trend, with bkn in BMI CMI and PIA... sct in the
south through tomorrow morning. Light and variable winds through
the overnight becoming more southerly tomorrow morning as the
ridge axis slips eastward.


&&

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

$$

SHORT TERM...HJS
LONG TERM...Bak
AVIATION...HJS






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