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fxus63 kilx 230200 
afdilx

Area forecast discussion
National Weather Service Lincoln Illinois
900 PM CDT Thu Aug 22 2019

Synopsis...
issued at 330 PM CDT Thu Aug 22 2019

Scattered showers and isolated thunderstorms will occur south of
I-72 into early evening, and linger in southeast Illinois much of
tonight as a frontal boundary pushes southward through southeast
Illinois. Dry, cooler and less humid conditions are on tap across
central Illinois from Friday through Sunday night as high
pressure settles into the Great Lakes region. Chance of showers
and thunderstorms will return to the prairie state on Monday into
Tuesday as a upper level disturbance and frontal boundary moves
into Illinois.

&&

Update...
issued at 900 PM CDT Thu Aug 22 2019

Precip has ended across most of the area, except for the extreme
southeast parts of the County Warning Area. However, this will not last long and
should be out of the area around midnight. Along, either side, and
south of I-70 clouds will continue into the overnight hours. So,
will be making some adjustments to location of pops/wx and
adjusting cloud cover to account for trends in satellite loops.
Remainder of the overnight forecast looks fine. Update will be out
shortly.

&&

Short term...(this evening through friday)
issued at 330 PM CDT Thu Aug 22 2019

Had several reports of brief small funnel clouds along a frontal
boundary south of I-72 past couple of hours. Have some moisture
convergence along this boundary that is slowly moving southward
and currently aligned from near Carrollton to Taylorville to
Tuscola to south of Danville. Could see a few more funnel clouds
along this boundary has it heads toward I-70 in a few hours. More
scattered showers and isolated thunderstorms were south of I-70
and tracking eastward. Laps convective available potential energy were 1000-1500 j/kg south of
boundary and to support isolated thunderstorms into early evening
in southeast. Kept chance of showers in southeast Illinois after sunset
thru much of tonight, though gradually diminishing from the north
overnight as frontal boundary pushes south of the County Warning Area. Cooler lows
overnight range from upper 50s north of I-72 and mid 60s se of
I-70.

1024 mb Canadian high pressure over western/northwest Ontario and
ridging southward into the upper Midwest, will settle into Lake
Superior area by sunset Friday, pushing the front south into the
Tennessee River valley and southern Arkansas. Brunt of County Warning Area should be dry on
Friday with more sunshine (partly to mostly sunny skies), though
kept slight chance of showers in far se Illinois early Fri. A bit
stronger NE winds on Friday to usher in less humid air into
central and southeast Illinois. Highs Friday in the upper 70s to near 80
degrees.

Long term...(friday night through thursday)
issued at 330 PM CDT Thu Aug 22 2019

Canadian high pressure to Camp out over the Great Lakes region
on Saturday and start drifting eastward on Sunday but still
influencing central il's weather. This high pressure will bring
delightful weather to central and southeast IL, with dry wx and
comfortable temperature and humidity levels. Lows Friday and
Saturday night in the mid to upper 50s, coolest NE County Warning Area. Highs Sat
in the upper 70s and upper 70s to near 80f on Sunday. Lows Sunday
night mostly in the lower 60s.

Medium range models dig a northern stream short wave trof into the
northern plains and Midwest on Monday and bring a good chance of
showers and some thunderstorms to the area by Monday afternoon
into Monday night. Best chance of showers and isolated
thunderstorms shifts into eastern/se Illinois on Tuesday with slight
chances over the Illinois River valley, as upper level trof axis shifts
eastward and front moves east into Indiana by midday Tue. Highs
Monday in the lower 80s, then a few degrees cooler on Tuesday.
Looks like a break in convection chances Tue night and possibly
into Wed, then another chance of showers and thunderstorms by
late Wed afternoon and Wed night as another upper level trof
shifts se into Illinois with a secondary frontal boundary moving in.

&&

Aviation...(for the 00z tafs through 00z Friday evening)
issued at 625 PM CDT Thu Aug 22 2019

VFR conditions will prevail at all taf sites next 24hrs. Thicker
clouds have shifted south and based on satellite loops should
continue to shift south and east away from all taf sites. So all
sites will scattered high clouds this evening and overnight. With
a boundary in southern Illinois tomorrow, some mid clouds could advect
back into the I-72 corridor area tomorrow morning. Plus a little
bit of cumulus is possible as well. So for late morning through the
afternoon will have few cumulus with scattered mid clouds at
spi/Dec/cmi. Pia and bmi could see some cumulus as well, but higher
scattered clouds. Winds will be light and variable this evening
through overnight, then east winds expected at around 10kts at all
sites for late morning through afternoon.



&&

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

$$

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