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Area forecast discussion...updated aviation 
National Weather Service St Louis MO
655 am CDT Wed Aug 27 2014

Synopsis:
issued at 237 am CDT Wed Aug 27 2014

Front is slowly making progress into the County Warning Area early this morning
and is currently stretching from near Kansas City, Missouri to
Quincy, Illinois. Some isolated thunderstorms continue to pop up
here and there on outflow boundaries across eastern Missouri and
west central Illinois, with a better defined cluster of convection
now taking shape across far northwest Missouri. Temperatures
remain mild with all locations still in the 70s this morning.

Cvking
&&

Short term: (through tonight)
issued at 237 am CDT Wed Aug 27 2014

Elevated convection will continue to develop across northern
Missouri early this morning with scattered thunderstorms forecast
through the lunch hour across the northern counties of the County Warning Area.

Front will make very slow progress south today. Temperatures will
quickly rise into the 90s south of the front and due to pooled
dewpoints in the lower to middle 70s, produce at least a few hours
of heat indices above 100 degrees along and south of I-70. Although
it won't be as hot as the past few days - feel current heat
headlines are warranted given potential for one more day of heat
indices reaching 105 degrees this afternoon.

The front will also serve as the focus for convective initiation
with scattered thunderstorms expected along and south of I-70 this
afternoon. As was the case yesterday, a few of the storms could
produce some gusty winds to 50 mph and torrential downpours.

Diurnal convection expected to dissipate quickly after sunset with
the focus for more elevated development shifting back north of the
boundary across the northern reaches of the County Warning Area after midnight.

Cvking

Long term: (thursday through tuesday)
issued at 237 am CDT Wed Aug 27 2014

Boundary will be slow to lift back north on Thursday and may become
orientated more northwest to southeast across the County Warning Area...paralleling
the Mississippi River. Once again, afternoon convection will be
possible in the vicinity of this front.

The boundary should finally lift north as a warm front Thursday
night with dry and seasonably warm weather expected on Friday
ahead of the shortwave/cold front that approaches from the west.

Have tried to focus likely pops Friday night and Saturday with this
next system as blended guidance seems to give too long of a period
of pops when compared to reality. So, after a wet and cooler
beginning to the Labor Day weekend, it appears chances of
precipitation will decrease for Sunday and Monday (labor day), with
temperatures beginning to inch back up above normal in the wake
of this storm system.

Cvking
&&

Aviation: (for the 12z tafs through 12z Thursday morning)
issued at 655 am CDT Wed Aug 27 2014

Complex of storms continues to develop over northwestern Missouri
and track to the east. Should move into KUIN by 17z and persist
through the afternoon hours. Otherwise, trying to pin down when
storms may develop and move through other tafs sites is difficult,
so for now kept tafs dry. Light winds to pickup from the northeast
to east today as frontal boundary settles over region. Some patchy
dense fog has developed over central MO, but should lift and
dissipate by mid morning today. By tonight, front will be just
south of Interstate 70, so could see some patchy MVFR fog develop
after 06z Thursday, so added tempo mention.

Specifics for kstl:

Complex of storms continues to develop over northwestern Missouri
and track to the east. Should move remain north of Metro area.
Otherwise, trying to pin down when storms may develop and move
through Metro area is difficult, so for now kept taf dry. Light
winds to pickup from the northeast to east by 18z as frontal
boundary settles over region. By tonight, front will be just
south of Interstate 70, so could see some patchy MVFR fog develop
after 08z Thursday, so added tempo mention.

Byrd
&&

Lsx watches/warnings/advisories:
MO...heat advisory until 8 PM CDT this evening for Audrain MO-Boone
MO-Callaway MO-Cole MO-Crawford MO-Franklin MO-Gasconade MO-
Iron MO-Madison MO-Moniteau MO-Montgomery MO-Osage MO-
Reynolds MO-St. Francois MO-Ste. Genevieve MO-Warren MO-
Washington MO.

Excessive heat warning until 8 PM CDT this evening for Jefferson
MO-Lincoln MO-St. Charles MO-St. Louis city MO-St. Louis MO.

Illinois...excessive heat warning until 8 PM CDT this evening for Bond Illinois-
Calhoun Illinois-Clinton Illinois-Fayette Illinois-Greene Illinois-Jersey Illinois-
Macoupin Illinois-Madison Illinois-Marion Illinois-Monroe Illinois-Montgomery Illinois-
Randolph IL-St. Clair Illinois-Washington Illinois.

&&

$$
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