Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 180751

Area Forecast Discussion
National Weather Service Saint Louis MO
251 AM CDT Sun Jun 18 2017

.SHORT TERM...  (Through Late Tonight)
Issued at 250 AM CDT Sun Jun 18 2017

Complex of thunderstorms that moved across much of the area has
pushed southeast of the CWA as the cold front continues to move to
the southeast. Lingering showers and a few thunderstorms will be
possible through midday over the southeast half of the CWA as there
will still be some ascent ahead of mid-level trough that will move
across Missouri and Illinois later in the day.  Clouds will clear
out slowly today and there will be some cold air advection which
will allow for cooler temperatures than yesterday. A blend of MOS
highs look good for today.

Skies will turn mostly clear behind the mid level trough axis
tonight.  With light westerly winds tonight and limited clouds,
temperatures should be able to fall to the agreeable MOS lows
near 60 degrees.


.LONG TERM...  (Monday through Saturday)
Issued at 250 AM CDT Sun Jun 18 2017

Looks like a period of quieter weather for the area through the
middle of next week.  High pressure at the surface and northwest
flow aloft through Tuesday should keep temperatures near normal with
lower humidity than we`ve had the past few days.  The high will
drift east of the area on Wednesday and southerly flow will bring
higher humidity and warmer temperatures back to the area.  GFS and
ECMWF both develop a low level jet Wednesday night as the next
upstream trof strengthens over the Great Plains and the associated
850mb moisture convergence forces some nocturnal convection over
western and northern portions of the CWFA late Wednesday night.

Medium range models diverge toward the end of the week with the GFS
developing a deeper longwave trof over the central CONUS than the
ECMWF toward the end of the week.  This makes the GFS faster in
shifting a cold front southeast through the Plains into the Midwest
than the ECMWF.  The result is that Friday and Friday night are
wetter on the GFS as the front moves through while the ECMWF is
warmer and wetter on Saturday.  Stuck closer to ensemble forecasts
which lean toward the GFS that far out with likely PoPs Friday night
and a mostly dry and cooler Saturday.



.AVIATION...  (For the 06z TAFs through 06z Sunday Night)
Issued at 1257 AM CDT Sun Jun 18 2017

Complex of thunderstorms will move across the St. Louis area terminals
early in the period bringing MVFR/IFR ceilings and visibilities
and possible wind gusts to 35kts. The chance for showers and scattered
thunderstorms will continue through 13Z. Then dry and VFR
conditions is expected the rest of the period with west to
northwest winds.

SPECIFICS FOR KSTL: Thunderstorms are expected early in the period
with MVFR/possible IFR conditions through 08Z with gusty winds.
Then a chance of showers and thunderstorms will continue through
10Z with dry and VFR conditions thereafter. West to northwest
winds are expected most of the period.



Saint Louis     81  63  83  65 /  30   5   5   5
Quincy          78  59  80  59 /  10   5  20   5
Columbia        80  59  82  61 /  20   5   5   5
Jefferson City  81  58  83  61 /  30   5   5   0
Salem           81  61  82  61 /  50   5   5   5
Farmington      79  59  82  59 /  50  10   0   0




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