Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 062049

349 PM CDT TUE OCT 6 2015

.SHORT TERM:  (Through Late Tonight)
Issued at 349 PM CDT Tue Oct 6 2015

Rather stagnant weather pattern continues due to an an upper level
omega block over the CONUS.  Weak high pressure over the Midwest at
the surface will remain in place through tonight.  Guidance is
inconclusive with regards to the cloud forecast for tonight, so
between that and the stagnant pattern I stuck with persistence.
Dewpoints are currently in the mid 50s to around 60, and forecast
lows tonight are expected to drop to near those values.  Expect
light wind to allow for fog to develop, although I think the
lingering cloud cover will keep the fog from getting to thick.


.LONG TERM:  (Wednesday through Next Tuesday)
Issued at 349 PM CDT Tue Oct 6 2015

Shortwave just now moving onshore over Washington/B.C. will round
the top of the ridge over southwest Canada and dive into the Great
Plains Wednesday night.  The surface reflection of this wave will
move across the Upper Midwest into the Great Lakes region on
Thursday.  The resulting cold front will move southeast into
Missouri Thursday night.  This is slower than previous forecast, but
guidance seems to be in good agreement on this timing.  Expect
showers and thunderstorms along and ahead of the front, though am
not confident on coverage. The front will be coming through at night
which is climatologically not favorable for widespread thunderstorms
in this pattern.  Model QPF seems to agree with me as amounts are
light and somewhat spotty.  Front should clear our southeast
Missouri/south central Illinois counties by late morning/early
afternoon Friday.

Temperatures ahead of the front Wednesday and Thursday will remain
well above normal with lows in the in the mid 50s and highs 70s to
around 80. After the front passes Friday we should see temperatures
drop back to near or just below normal in the mid 60s to low 70s
with lows 45 to 50.  The surface high behind Thursday night/Friday`s
cold front will move south of the area on Sunday and the wind will
turn back around to the southwest.  Temperatures warm back up to
around 80 for next week.



.AVIATION:  (For the 18z TAFs through 18z Wednesday Afternoon)
Issued at 1252 PM CDT Tue Oct 6 2015

A swath of MVFR CIGs stretching from SW MO NE into SE IA are in
the process of rising early this aftn. Think that all areas will
become VFR by later this aftn...but it will be a slow process due
to plenty of mid/high clouds streaming overhead. Guidance
indicates that areas where the stratus persists thru the aftn may
see CIGs build back down to MVFR levels after midnight. Models are
also suggesting more MVFR fog towards early morning as well. Not
confident in either of these so have left out of the fcst for
now. Otherwise expect plenty of VFR clouds thru the prd with light
Nrly flow below 10 kts.

Specifics for KSTL:

Plenty of VFR clouds thru the fcst prd with the potential for a
few hrs of high end MVFR VSBYs towards sunrise Wed mrng. Not
confident enough to include in the fcst attm.



Saint Louis     60  79  62  86 /  10   5   5  10
Quincy          56  78  59  84 /  10  10  10  40
Columbia        56  78  58  84 /  10  10  10  10
Jefferson City  56  77  58  82 /  10  10  10  10
Salem           56  78  59  84 /  10   5   5  10
Farmington      56  76  57  82 /  10  10   5  10




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