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FXUS63 KILX 282359

National Weather Service Lincoln IL
559 PM CST SAT NOV 28 2015

.SHORT TERM...(Tonight)

High pressure is building into the region slowly, but the stalled
front south of the Ohio River Valley is keeping the cloud cover in
place over the forecast area this afternoon.  Some showers remain in
the wake of the boundary as a small disturbance ripples through the
increased RH in the mid levels.  Not all of the echoes on radar are
producing precip, but south of I-70 is seeing a better chance, and
that will remain the trend through the overnight.  Drier air pushing
in from the north with the northerly winds overnight will continue
to erode the llvl moisture. As a result, the stratus may start to
erode as well, but mid level RH will keep the clouds in place for
the overnight hours.  Clouds will also keep the overnight lows from
bottoming out entirely, but any breaks in the clouds may allow for
some variability across the northern tier of the state.  The
southern half of the state will remain above freezing.

.LONG TERM...(Sunday through Saturday)

Models continue their trend southward with the main precip area on
Sunday, but several of the hi-res solutions do indicate some light
precip approaching the far southwest early Sunday morning. Forecast
soundings continue to indicate a very dry atmosphere from around
1200 to 5000 feet, so the main question is whether any precip will
get to the ground during this time frame, and what type of precip
it will be over far west central IL. NAM indicating the better
forcing/isent ascent will be to our west late tonight into Sunday
morning with any lingering precip drying up before it gets into
our area. The GFS is still holding on to the idea of some light
QPF pushing into west central IL by Sunday morning. Problem with
that is that temperatures in this area are forecast to be close to
freezing, but feel it will have a tough time getting to the ground,
so will continue with just slight chances in the morning hours over
far west central thru southeast IL and keep the precip type as rain
with temperatures a degree or two above freezing.

Large upper low finally gets a nudge to the northeast later Sunday
from an upstream shortwave approaching the Pacific Northwest on
Monday. This should help drag the frontal boundary well to our
south this afternoon up our way later on Sunday into Sunday night.
Other than the slight chances of precip over far west thru southeast
Illinois Sunday, the remainder of the forecast area looks dry with
the main push of rain late Sunday night and especially on Monday.
The latest ECMWF/Canadian and Short Range Ensemble indicate the
upper low to track to near Green Bay by Tuesday evening, while the
GFS is a bit further north. Using the ECMWF placement would put some
wrap-around flurries into our far northern area Tuesday night before
the system pulls away from our area on Wednesday.

In the wake of the storm system, seasonably cold weather will follow
for Wednesday and Thursday before we see temperatures gradually
moderate at the end of the week as upper level heights build over
the Midwest in response to another trof digging into the western
portion of the country. Mex guidance suggesting highs close to or
just above 50 by Friday and next weekend with little if any precip
indicated from the medium range models.


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

MVFR CIGS will continue to slowly scatter out across the central
Illinois terminals this evening under dry low-level northeasterly
flow, although mid-level VFR CIGS will remain. Northeasterly winds
should fall below 10 kts at most TAF sites this evening, and will
persist for the remainder of the 00Z TAF valid time.


.ILX Watches/Warnings/Advisories...


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