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FXUS63 KILX 020309

National Weather Service Lincoln IL
909 PM CST TUE DEC 1 2015


Current forecast looks on track with pcpn entering the cwa in the
northwest and west late this evening and then slowly spreading
eastward overnight. Most of pcpn is rain, but have had one report
of a mix of rain and snow in northern Knox county. Clouds also
slowly moving in with clearing still in the east and southeast.
Will take a look at clouds and may need to make some adjustments
there. If no cloud updates needed, then not update will be sent,
otherwise look for an update in next couple of minutes.


.SHORT TERM...(Tonight)

Large upper low spinning over north central Iowa early this
afternoon, with various shortwaves rotating counter-clockwise around
it. Snow showers have been advancing eastward across Iowa through
the day with some mixed precipitation being reported as far east as
Cedar Rapids by 2 pm. Cirrus clouds over the southeast parts of the
forecast area have been thinning the last few hours, and earlier
stratocumulus over the northwest corner has moved away, but a large
shield of lower clouds is advancing across the Illinois/Iowa border.

Main concern for tonight remains with precipitation timing. HRRR
model has been suggesting some increase in precipitation further
south across Missouri this afternoon, ahead of an upper wave near
Kansas City, and some echoes are starting to be seen in northern
Missouri with light rain as close as Kirksville. A surface boundary
ahead of it is progged to sharpen a bit as it moves into central
Illinois this evening, with PoP`s gradually increasing as the
boundary arrives. Currently thinking most areas east of I-55 should
remain dry until after midnight, until a second wave currently over
southeast Nebraska swings into the area. Have increased PoP`s a bit
and went likely (60%) for a couple hours north of Bloomington after
about 3 am. With temperatures near or just above freezing, a
rain/snow mix should gradually change to snow, but accumulations
still expected to be mainly a quarter inch or less with slightly
higher totals north of I-74. Mainly sprinkles/flurries are expected
south of I-72, and areas south of I-70 likely to remain dry until
early Wednesday morning.

.LONG TERM...(Wednesday through Tuesday)

The large 500 mb low we have watched inch its way out of the
Rockies late in the weekend and early this week will be edging east
across far southern Wisconsin Wednesday and into extreme northwest
Indiana by early evening. This system will bringing cooler
conditions to the forecast area along with scattered snow showers,
especially across the north, which may mix or change to light rain
or sprinkles in the south during the afternoon. The stronger lift is
forecast to push in early Wednesday morning and gradually shift east
of the area during the afternoon. If we are going to see any
accumulation along and north of I-74, it would be in the morning, as
surface temperatures are expected to rise into the mid and upper 30s
by mid-afternoon. The snowfall should total less than one inch
across the north, with little, if any accumulations further
south. The precip threat should shift east of the forecast area by
late afternoon or early evening as the 500 mb trof axis edges east
into Indiana by then.

Upper level heights will gradually build across the Midwest by the
end of the work week as a trof moves into the western part of the
country. This will bring unseasonably mild weather back into the
region starting on Friday and holding into at least the first few
days of next week with afternoon temperatures closing in on 50
degrees far north and well into the 50s elsewhere. Models continue
to show their differences, at least compared to 24 hours ago, with
respect to shortwave energy coming out of the southwest portion of
the country late this weekend and especially into early next week.
The latest ECMWF indicated a closed 500 mb low pushing across
south-central Illinois on Monday, whereas the GFS was much further
south. The Euro solution puts rain back into at least the southern
half of the forecast area, where the GFS track keeps us dry. No
reason to make any significant changes early next week based on
what we saw today with the 12z runs, so will continue to keep
only slights going in the southerly quarter of the forecast area
on Monday with the above normal temperature regime holding into a
good portion of next week.


.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)

Skies are currently clear at all TAF sites, but still believe
clouds will advect over the sites later this evening from the an upper level system slowly moves east into the area.
Clouds will be above 3kft at the start but then fall to MVFR
levels during the overnight and early morning hours. Based on HRRR
and NAM12 RH fields, looks like there will be several hours of a
break in the clouds before more MVFR clouds advect into the area
for later in the morning through the afternoon. Southwest winds
will become westerly after midnight as the main surface trough
moves through the area. Wind speeds should remain around 10kts of
less through the night and then increase in the late morning
through afternoon. Light rain showers will be possible this
evening, but with the lower clouds coming in later and temps
cooling off, it will switch to light snow showers. Models not
indicating lots of pcpn, and think it will be more scattered and
isolated, so just going with VCSH most places and a tempo group
after midnight in the north, closer to the forcing.


.ILX Watches/Warnings/Advisories...


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