Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 062316

616 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 00z TAFs through 00z Wednesday Evening)
Issued at 609 PM CDT Tue Oct 6 2015

Current thinking is that clouds/stratus will persist through
Wednesday morning with CIG heights from high-end MVFR to low-end
VFR. Any areas which see breaks could see redevelopment of thicker
clouds and/or fog reducing the visibility to 3-5sm. Tough call on
what will occur with the clouds on Wednesday but present
indications are for rising bases and more cumuliform structure
with VFR flight conditions by the later half of the morning.

Specifics for KSTL:

Current thinking is that clouds/stratus will persist through
Wednesday morning with CIG heights in the low-end VFR flight
category. On Wednesday the present indications are for rising
cloud bases and more cumuliform structure with VFR flight



Saint Louis     60  79  62  86 /   0   5   5  10
Quincy          56  78  59  84 /   0   5  10  40
Columbia        56  78  58  84 /   0   5  10  10
Jefferson City  56  77  58  82 /   0   5  10  10
Salem           56  78  59  84 /   0   5   5  10
Farmington      56  76  57  82 /   0   5   5  10




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