Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 210149

Area Forecast Discussion
National Weather Service Lincoln IL
849 PM CDT Thu Apr 20 2017

Issued at 849 PM CDT Thu Apr 20 2017

Surface observations indicating the cold front that affected
central IL today has now reached Lawrenceville and is exiting
the forecast area. Stabilizing conditions behind the front will
bring an end to any shower/thunderstorm chances this evening while
brisk NW winds gusting up to 20 mph set in behind the front. Much
cooler temperatures will continue to advect into the area for lows
in the 40s to lower 50s. Minor updates for trends in PoPs and
winds this evening.


.SHORT TERM...(This evening through Friday)
ISSUED AT 309 PM CDT Thu Apr 20 2017

Surface low positioned over the Great Lakes this afternoon is
trailing a cold front through the Midwest and Eastern Illinois back
through to the Southern Plains. The cold front is easily discernible
on radar as well as in the obs, and scattered showers and
thunderstorms still exist in advance of the boundary...and will
likely continue through at least the early evening.  On the other
side of that, there should be a brief clearing in the overnight
hours before more clouds move in tomorrow...increasing through the
afternoon.  Overnight lows will drop into the 40s in central
Illinois this evening...and clouds and northerly winds will keep the
high temps tomorrow in the 50s.  Rain chances tomorrow will return
in the southern tier of the state as the stalled front slowly
reverses as a warm front in the afternoon hours.

.LONG TERM...(Friday night through Thursday)
ISSUED AT 309 PM CDT Thu Apr 20 2017

Friday night and into Saturday, precip chances will surge northward
as another wave ripples along the slow moving boundary, up into the
Midwest.  Rain will keep the temperatures down, particularly in the
southern half of the state, in the low to mid 50s. Areas to the
north should be a couple degrees higher, depending on the northern
extent of the showers that day.  Forecast slowly dries out Sat night
and into Sunday as a wave out of the northwest dives into the weak
trof aloft, amplifying the wave pattern over the eastern half of the
CONUS and moving out to the east. Sunday will be mostly dry, sunny,
and far more seasonable for Spring, with highs in the mid to upper

High pressure ridge slips eastward overnight Sunday into Monday
morning.  Southerly winds on the other side of the ridge sets up a
warm advection pattern that lasts at least through early Tuesday.
The forecast beyond that becomes somewhat sketchy with light pops in
the grids as the models work out the next series of short waves that
ripple across the country in mostly zonal flow.


.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 649 PM CDT Thu Apr 20 2017

VFR cigs expected the next 24 hours, however an area of near MVFR
cigs associated with the upper low moving eastward into the upper
Midwest will likely affect KPIA-KBMI-KCMI northward this evening
potentially into early morning until the upper low moves farther
east. In addition, scattered afternoon cloud cover around 3000 ft
AGL Friday could briefly become BKN. Winds NW 12-18 kts with
higher gusts this evening should diminish gradually through early
morning, turning northeasterly for Friday afternoon.




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