Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 191954

254 PM CDT Sat Jul 19 2014

.SHORT TERM: (Tonight through Sunday)
Issued at 246 PM CDT Sat Jul 19 2014

The large surface high centered in the northeastern U.S. continues
to influence conditions across the region producing yet another
day of below average temperatures. This system will gradually
weaken and retreat eastward over the next 24-36 hours as the eastern
trof departs and the four corners ridge builds eastward. We should
see at least one more seasonably "cool" night tonight, and then
more pronounced southerly flow gets underway on Sunday leading to
warming temperatures and increasing moisture/humidity.


.LONG TERM:  (Sunday Night through Next Saturday)
Issued at 246 PM CDT Sat Jul 19 2014

The upper ridge will continue to strenghthen and build through the
Nation`s midsection Monday into Tuesday leading to progressively
warmer temperatures and low-level moistening. Tuesday looks like
the hottest day of the upcoming week with conditions more typical
for later July. A pronounced low-level thermal ridge centered
through the northern half of the CWA featuring H85 temps of +20 to
+24 degC, warm mid levels and high heights aloft all favor max
temperatures well into the 90s. The pattern aloft will change once
again beginning Tuesday night with higher latitude amplification
and more progressive flow aloft in the vicinity of the U.S./Canadian
border, leading to upper troffing in the eastern U.S. and flattening
and retrogression of the upper high into the the southwestern U.S.
A cold front will push through the area in the late Tuesday night/Wednesday
time frame as a result of this pattern transition/change, bringing
a chance of showers and thunderstorms and then cooler temperatures
during the later half of the week. This front will then make a
northward return bringing a return of thunderstorm chances heading
into the next weekend.



.AVIATION:  (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1214 PM CDT Sat Jul 19 2014

VFR through the period with diurnal cu developing between 14-16z
and dissipating around 00-02z. Initially light winds will become
southeasterly to southerly around the back side of a high pressure





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