Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 250946

Area Forecast Discussion
National Weather Service Saint Louis MO
446 AM CDT MON JUL 25 2016

.SHORT TERM...  (Through Late This Afternoon)
Issued at 348 AM CDT Mon Jul 25 2016

Convection will continue to percolate today invof a slow-moving
cold front. As the previous shift noted, the dew point gradient is
lagging several hours behind the wind shift. The dew point
gradient may serve as an additional focus for SHRA/TSRA dvlpmt
today. The overall trend will be for pcpn to sink southward with
the cdfnt.

Temperatures will be around 5-10 degrees cooler tdy compared to
ydy across most of the CWA except for the far southern CWA and
eastern Ozarks. Those areas may experience some warming before
pcpn sinks southward.


.LONG TERM...  (Tonight through Sunday)
Issued at 348 AM CDT Mon Jul 25 2016

Conditions look unsettled this week. A cold front is forecast to
stall across the region this week, which will act as a focus for
pcpn. The presence of this bdry combined with several impulses
aloft moving through weakly NW flow will lead to periods of
SHRA/TSRA through the week. Pcpn should generally remain across
the southern half of the CWA until Wednesday, when the stalled
front begins to lift back northeastward as a warm front ahead of
an approaching vort max.

Daily high temperatures in the mid-80s to near 90 deg F will be
seasonably warm, and lower dew point values will create less
oppressive conditions compared to what occurred over the last
several days. Peak heat index values are expected to remain in
the 90s this week.



.AVIATION...  (For the 06z TAFs through 06z Monday Night)
Issued at 1149 PM CDT Sun Jul 24 2016

Focus will continue to be on convective trends through the rest of
the night and into early on Monday. Front is through KUIN with
just a few showers behind it so belive Quincy will be dry save a
few showers in the vicinity. KCOU should get a couple of hours of
showers and thunderstorms early in the period with gusty WSW winds
and heavy rainfall in a TEMPO group. Tough call for the metro TAFs
but SW-NE oriented boundary is oozing SE very slowly with KSTL
having the best chance of seeing thunderstorms early in the TAF
period compared to KCPS and KSUS...though they may get in on the
action a bit later tonight. For now...continued VCTS groups due to
undertainty later on tonight with convective trends. Winds behind
the front will swing to the northwest with diminishing chances for
showers and storms as we head from Monday morning into the
afternoon hours as the front continues to sag to the south of the

Specifics for KSTL:

Greatest concern in the next 6-9 hours will be on possibility of
thunderstorms affecting the terminal. Believe highest chance will
be within the first few hours and have added a TEMPO group for
MVFR visbys w/ the thunderstorms. IFR visbys along with wind gusts
are possible if a stronger storm affects the terminal.
Thunderstorms continue to be possible into Monday morning but
chances will diminish toward the afternoon hours. Winds have come
around to the northwest behind an outflow boundary and may now
stay that way the rest of tonight...though they could be a bit
variable direction wise over the next several hours.





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