Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 290553

Area Forecast Discussion
National Weather Service Lincoln IL
1153 PM CST Mon Nov 28 2016

Issued at 912 PM CST Mon Nov 28 2016

Rain is departing quickly to the northeast as dry air in the mid
levels arrives on brisk SW winds. Clouds are also clearing quickly
on the heels of the back edge of the rain. The NAM is indicating
we could see some low stratus could redevelop later tonight.
However, steady westerly winds the rest of the night should help
to preclude a strong low level inversion and low clouds from
developing, which is in line with the GFS.

Despite the clearing of clouds, which usually means colder night
time lows, steady winds should keep mixing in the low levels and
lows slightly warmer. Lows should settle out in the upper 30s NE
of the IL river, with mid 40s south of I-70.

Updated forecast info is already available.


.SHORT TERM...(This evening through Tuesday)
ISSUED AT 230 PM CST Mon Nov 28 2016

Rather large storm system located over the northern Plains and
making its way into the Upper Midwest this afternoon is the dominant
feature on the weather map today.  The cold front associated with it
is slow-moving, while plenty of warm air and moisture streams out of
the south up and into Central Illinois.  This, in combination with a
few shortwaves making their way around the larger scale trof, is
resulting in plenty of showers and thunderstorms for Central
ILlinois.  These showers are anticipated to come to an end later
this evening, clearing from west to east by midnight.  Overnight
lows still well above norms for the end of November.  Winds will
weaken from this afternoon, but still stay a little gusty at least
through the early evening.  Tomorrow will be a much quieter day,
with the skies clearing and temperatures a bit warmer with all the

.LONG TERM...(Tuesday night through Monday)
ISSUED AT 230 PM CST Mon Nov 28 2016

The main cold front associated with the weather system that brought
precip to the area will finally move through the CWA Tuesday night.
This will allow more normal temps to be ushered into the area for
the remainder of the week and into the weekend. Even with the area
remaining in cyclonic flow through most of the week, dry weather is
expected through the rest of the week and into the first part of the
weekend. High pressure will finally build into the region at the end
of the week and into Sat. For the rest of the weekend, the model
show considerable differences. The ECMWF develops a large weather
system in the southern Miss valley and drives it north-northeast
into the Ohio valley. This solution allows colder air to drop into
the area, resulting in a higher potential of precip for Sat night
through Sun night. Obviously with the colder air, the precip type
would likely be snow. On the other-hand, the GFS just has a weak
wave moving through the zonal flow, through the area. Temperatures
are not colder and the any precip would be light and a probably a
mix of rain and snow, with mainly rain during the daytime hours. Due
to the differences being stark, best to keep a blend of the models
going that far out, keeping pops on the low side in the chance
category. Temps will likely be slightly below normal so precip type
will end up being a mix of rain and snow. This being the second day
in a row of the models being this different leads to low confidence
in the forecast for the nothing to get excited about at
this time.

Again, temps will be above normal again tomorrow, with plenty of
sunshine and less windy. Beyond tomorrow, temps will fall to just
below normal, or around normal, for the remainder of the forecast


.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1153 PM CST Mon Nov 28 2016

One initial concern is for LLWS conditions as winds diminish in
our NW counties. PIA may see 3 hours of LLWS conditions before the
winds in the 2K Ft level diminish. The other terminal sites have
stronger winds lingering longer, and will diminish at the surface
in concert with the low level jet winds.

The rains and MVFR clouds have departed to the northeast of all
our terminal sites, with CMI just clearing in the last 30 mins.
VFR conditions should prevail for the remainder of the TAF period,
with help from steady winds the rest of tonight preventing much in
the way of fog to form under mostly clear skies.

The forecast soundings are indicating we could see a wave of mid-
level clouds progress across Illinois tomorrow, but there will be
little affect on aviation.

Winds will remain gusty for a few more hours for our eastern
terminals. Gusts will become less strong later tonight. Winds
tomorrow will sustain in the 12-15kt range from the south.




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