Area Forecast Discussion
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FXUS63 KILX 261746

Area Forecast Discussion
National Weather Service Lincoln IL
1246 PM CDT WED OCT 26 2016

Issued at 1038 AM CDT Wed Oct 26 2016

Moisture channel imagery and upper air this morning illustrate
shortwave from southeast MN to central KS. Wave is relatively
weak, with SPC page displaying limited shear and main instability
further south of IL, ahead of frotn over southewest MO and OK.
Surface low over IA progged to continue to track to the east
today. 850mb and surface analysis shows moisture axis into mo with
drier air in IL. As front moves to the east, some scattered pcpn
possible with front, with moisture just ahead of boundary for
southern 1/2 of cwa. For the northern half, better dynamics with
low center moving east over northern IL. So better minor lift and
this will keep better chance of pcpn in northern 1/2 of region
today and early this evening.


.SHORT TERM...(Today and tonight)
ISSUED AT 328 AM CDT Wed Oct 26 2016

An area of low pressure, currently over western Iowa, will
track eastward to northern Indiana by midnight tonight. The
trailing cold front is expected enter the by this afternoon, and
exit the forecast area to the east by shortly after midnight.
Showers and thunderstorms are likely along and ahead of the
frontal boundary, and will begin to push into the forecast area
from the west later this morning. Severe weather is not
anticipated with any of the storms given the very modest shear
profiles and instability anticipated. It will be a pretty nice day
ahead of the front with widespread 60s anticipated. Some readings
over 70 are likely south of I-70. On the down side, it will be
rather cloudy, and gusty southerly winds are expected. Drier
conditions will filter into the area overnight behind the front.
Overnight lows will be mild for late October, bottoming out in the
mid 40s to lower 50s.

.LONG TERM...(Thursday through Tuesday)
ISSUED AT 328 AM CDT Wed Oct 26 2016

1011 mb low pressure over western IA will track eastward to
western Lake Erie by 12Z/Thu and over Lake Ontario by sunset Thu.
Showers will already be east of IL by sunrise Thu with clouds
decrease from the west during the day as 1024 mb high pressure
moves into IL/IN with skies becoming partly to mostly sunny Thu
afternoon. Cooler highs in the upper 50s and lower 60s with
mildest reading sw CWA. Lows Thu night in the low to mid 40s,
coolest over east central IL.

Cool down will be brief as breezy southerly winds develop on Friday
as surface high pressure ridges drifts off to the mid Atlantic
States and a cold front moves into central parts of MN and Nebraska.
Some upper level ridging into IL on Friday as well with 500 mb
heights rising just above 582 dm. Highs Fri of 70-75F and warmest
over west central IL. Milder lows Fri night in the upper 50s to
near 60F. Even warmer on Saturday with highs in the mid to upper 70s
with partly to mostly sunny skies and sw breezes.

00Z forecast models trending further south with some frontogenetic
forcing on Sat night with a chance of showers over northeast CWA
by overnight Sat night especially from I-74 northeast. A frontal
boundary will press southward over central IL overnight Sat night
and into southeast IL on Sunday. Lows Sat night in the low to mid
50s. Highs Sunday range from the low to mid 60s from I-74 north to
the lower 70s south of I-70.

Temps warm back up on Monday (Halloween) with increasing southerly
flow ahead of another approaching cold front moving into MN and
eastern Nebraska by Monday afternoon. Also have upper level ridging
back into the Ohio river valley. Highs Monday back into the mid 70s.
The cold front will push southeast over central IL overnight Monday
night into Tue and currently appears to pass through dry with
limited moisture to work with. A bit cooler highs Tue over central
IL ranging from mid 60s by Galesburg and Lacon to near 75F by


.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1242 PM CDT Wed Oct 26 2016

Radar shows pcpn band crossing central IL at TAF issuance time.
Some instability on the forward edge of the band. This is enough
for scattered area of storms. Some development still possible on
the forward edge and so brought down cigs in tstms early, then
scattered showers until the front approachs by early evening.
Lower cigs with the front will bring conditions down to ifr, which
will last all night and then during late morning some improvement


.ILX Watches/Warnings/Advisories...


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