Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 191809

109 PM CDT Sun Oct 19 2014

Issued at 912 AM CDT Sun Oct 19 2014

Made a few slight adjustments to the temperatues over parts of
south central Illinois into the St. Louis area. Also lowerrd the
temps a bit over parts of Warren, Montgomery and Franklin counties
however, expect relative quick recovery with the full sunshine.



.SHORT TERM:  (Through Monday)
Issued at 317 AM CDT Sun Oct 19 2014

The Canadian high pressure center which was located overhead early
this morning will shift southeastward today. Surface winds are
forecast to become southerly to southwesterly around the back side
of the high and ahead of an approaching cold front. The
clipper-like feature which will eventually drive this cold front
through the area was still located along the Alberta/Saskatchewan
border at 19/06z, but it is forecast to deepen and amplify as it
moves into the Great Lakes region tonight and tomorrow. Models
show limited moisture being drawn into the region ahead of the
cold front, and this should be sufficient for sprinkles or light
rain showers. Even though the strongest lift will be farther to
the east, an additional source of weak lift over the southern LSX
CWA may be provided early this evening by a compact vort max
which was located near the OK panhandle this morning. This feature
looks a bit stronger on water vapor imagery than the models would
suggest, and it was already producing light radar returns across
northern OK and southern KS. Precip chances diminish quickly after
18z tomorrow due to subsidence behind the front, decreasing
moisture, and decreasing lift as the low pressure system pulls
away from the area.


.LONG TERM:  (Tuesday through Saturday)
Issued at 317 AM CDT Sun Oct 19 2014

The rest of the forecast looks dry and seasonably warm through the
middle of the week. A surface ridge axis will extend southwestward
from Ontario into MO/IL while an amplified upper ridge shifts
eastward over the area. There may be a chance of rain late in the
week (Thu/Fri) if the models are correct in developing a closed
low over the southern plains and if its influence extends far
enough eastward to affect sensible wx over MO/IL.



.AVIATION:  (For the 18z TAFs through 18z Monday Afternoon)
Issued at 1244 PM CDT Sun Oct 19 2014

High pressure extending across the Ohio Valley region will
continue to move eastward into West Virginia and areas to the
east. Weak frontal boundary over North Dakota expected to move
southeast and move through eastern Missouri and southwest and
west-central Illinois between 1000-1500 UTC on Monday. Widely
scattered light showers and sprinkles are possible dueing and
after the frontal passage.

Specifics for KSTL:High level cloudiness will remain over the area
through late this afternoon. Southwest winds of 6-7 kts are likely
during the afternoon. Mid-level cloudiness will move into STL area
after 02 -0300 UTC this evening. Lower clouds around 050 Kft will
move into STL area after 1000 UTC. Widely scattered light showers
or sprinkles are possible between 1000-1500 UTC Monday morning.





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