Area Forecast Discussion
Issued by NWS Central Illinois

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FXUS63 KILX 221502

Area Forecast Discussion
National Weather Service Lincoln IL
1002 AM CDT SAT OCT 22 2016

Issued at 1002 AM CDT Sat Oct 22 2016

15z/10am surface analysis shows ridge axis extending from the
Great Lakes to the western Gulf, with southerly return flow
developing across central Illinois. Skies are mostly sunny around
the area: however, a patch of WAA cloud cover is noted on latest
visible satellite imagery sliding southeastward out of northern
Illinois. Based on satellite loops, it appears these clouds will
spill into the NE KILX CWA around Champaign and Danville this
morning, temporarily creating partly to mostly cloudy conditions.
Models indicate this area of mid-level moisture will push further
eastward later today, so am expecting a return to mostly sunny
skies across the board by early to mid-afternoon. High
temperatures will range from around 60 near the Indiana border to
the middle to upper 60s in the Illinois River Valley.


.SHORT TERM...(Today and tonight)
ISSUED AT 329 AM CDT Sat Oct 22 2016

The ridge axis associated with a large surface high currently cuts
across the forecast area from the southwest to the northeast. As the
ridge axis slips further to the southeast during the period,
southerly return flow will cause temperatures to warm. Today`s
expected highs in the 60s, and tonight`s expected lows in the 40s,
are closer to normal than they have been the past couple of days.
Otherwise, a dry airmass is expected to be in place through the
period. This will keep our quiet weather going with minimal cloud

.LONG TERM...(Sunday through Friday)
ISSUED AT 329 AM CDT Sat Oct 22 2016

Pleasant fall weather will continue Sunday across central and
southeast IL with even milder temperatures as surface high pressure
settles over the southeast states. Sunny skies and breezy southwest
winds gusting 20-25 mph should push highs into the 70-75F range on
Sunday afternoon, with warmest readings from Springfield sw. 850 mb
temps elevate to 12-14C on Sunday and supports these milder readings.

1009 mb surface low pressure to track across the upper MS river
valley Sunday morning, into the southern great lakes on Sunday night.
This will push a cold front southeast across central IL Sunday
evening and existing southeast IL overnight Sunday night. This front
has very limited moisture to work with and should come through dry
which models have been consistent on. Lows Sunday night in the mid
to upper 40s, with Galesburg reaching the lower 40s. A fair amount
of sunshine expected Monday as 1030 mb high pressure settles into
the Midwest behind the cold front, with more seasonable highs in the
low 60s central IL and mid 60s southeast IL with NNE winds 5-10 mph.
High pressure ridge passes east of IL into IN by Monday evening with
fair skies and a seasonably cool night in the low to mid 40s
(coolest readings near IN border). Another dry day expected Tue with
highs again in the low to mid 60s, with clouds increasing over
northern CWA ahead of next approaching wx system.

IL is in a nw upper level flow early next week, and transitions to a
semi-zonal and progressive upper level flow by middle of next
week. This to bring mid level short wave and associated surface
low pressure east into western IA by 12Z Wed and into
central/northern IL Wed night. Have 20-40% chance of showers and
isolated thunderstorms moving into areas from the IL river nw
overnight Tue night. Showers then likely spreading eastward across
the rest of central and southeast IL during Wed and Wed evening
with a chance of thunderstorms. Highs Wed range from lower 60s
northern CWA to upper 60s in southeast IL with Lawrenceville near
70F where showers arrive later in the day. Showers to diminish
from west to east after midnight Wed night with just slight
chances of showers near the IN border Thu morning. Clouds to
decrease from west to east during the day Thu. Cooler highs in the
lower 60s Thu with some upper 50s northern CWA.

Extended models differ with wx pattern later next week and stayed
close to consensus with dry conditions Thu night and Friday and
highs in the 60s. Upper level heights to stay above normal late
next week, keeping colder Canadian air locked north of our area.


.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
Issued at 633 AM CDT Sat Oct 22 2016

Quiet/VFR aviation weather conditions expected through the 12Z TAF
valid time. Cloud cover will be minimal through the period.
Variable winds will trend southwesterly as return flow develops on
the back side of a departing ridge of high pressure.


.ILX Watches/Warnings/Advisories...


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