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fxus63 kilx 170515 
afdilx

Area forecast discussion
National Weather Service Lincoln Illinois
1115 PM CST Sat Nov 16 2019

Synopsis...
issued at 1101 PM CST Sat Nov 16 2019

A cold front will approach the region Sunday bringing a good chance
of rain to much of the area Sunday afternoon and evening. The
precipitation may begin as a wintry mix Sunday morning, but any
amounts should be light.

&&

Update...
issued at 832 PM CST Sat Nov 16 2019

Have updated grids this evening to reflect the trend of slowing
pcpn onset early Sunday. In addition to the delay, it suggests
that pcpn will likely begin after surface temps have climbed above
freezing. Still could have a brief period of mix, but the trend is
to lessen the threat of any glaze.

&&

Short term...(this evening through sunday)
issued at 327 PM CST Sat Nov 16 2019

A cold front will approach and move into central Illinois Sunday,
bringing a good chance of light precipitation to most of central
Illinois north of I-70 for mainly the afternoon and evening. However,
some warm advection aloft ahead of the front early in the morning
could result in a few morning showers, while temperatures at the
ground remain near or below freezing from overnight lows in the
mid to upper 20s. This looks to bring a slight chance of brief
freezing rain anywhere from Taylorville to Danville northwestward.
Although accumulations should be minimal, slick areas could
develop until warmer temperatures develop late in the morning.
Highs should reach the low 40s.

Long term...(sunday night through saturday)
issued at 327 PM CST Sat Nov 16 2019

Following sunday's system, northwesterly flow aloft will continue
across central Illinois as long wave troughing develops over the eastern
U.S. There will be a potential for some fast moving clipper type
systems in the region around Tuesday, but predictability is too
low for mentionable precipitation chances at this point.
Fortunately, temperatures look to be warm enough that
precipitation would likely be light rain.

A stronger system looks to eject out of the southwest U.S. For
Thursday, and have included likely precipitation. Precipitation
amounts in the neighborhood of half inch look possible.

Temperatures will follow a general warming trend through
Thursday, as highs remain in the 40s Monday then reach the 50s
for Wednesday and Thursday. Cold air trailing the cold front with
thursday's system should bring highs back into the lower 40s for
Friday and Saturday.

&&

Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1115 PM CST Sat Nov 16 2019

Cirrus shield now moving into western Illinois. Ahead of the
clouds vsbys have occasionally fallen into MVFR. Will include a
tempo br group at kspi and kdec until clouds overspread those
sites.

Model trend from 00z is to slow pcpn onset once again bringing
pcpn into kpia during the early afternoon and then slowly
eastward. NGM/NAM from 00z suggests pcpn becoming more scattered
as it moves east. Although will keep a predominate group at
western terminals, will phase that down to prob30 at kbmi and kdec
and finally just a vcsh at kcmi. Cigs should fall into MVFR everywhere
along and immediately behind the cold front moving through the
terminals. This would time out to be around 00z from I-55 west and
2-4 hrs later at kdec and kcmi.

The wind shift with the front during the evening should be from
180-210 to 280-310, however, speeds should remain mostly blo 10
kts.



&&

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

$$

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