Area Forecast Discussion
Issued by NWS St. Louis, MO

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FXUS63 KLSX 261803

103 PM CDT Sun Apr 26 2015

.SHORT TERM:  (Through Late This Afternoon)
Issued at 245 AM CDT Sun Apr 26 2015

Quiet weather is expected today. Temperatures across the southern
two-thirds of the CWA may be initially slow to warm due to
extensive morning cloud cover, but temperatures ought to rise
quickly after the stratus scatters out this afternoon, allowing
highs to reach the lower 60s for most of the area.


.LONG TERM:  (Tonight through Saturday)
Issued at 245 AM CDT Sun Apr 26 2015

There is very little to discuss in the extended forecast. The
strong PV anomaly noted on 26/07z water vapor imagery near the
CA/AZ border is forecast to close off as it slowly progresses
eastward over the next few days, likely passing south of the CWA.
It is possible that the extreme southern CWA could be on the
extreme northern fringe of the precip shield, but confidence is
too low to introduce PoPs attm. There are some model differences
during the middle of the week with respect to a northwest flow
vort max and its interaction with the aforementioned slow-moving
low pressure system, but moisture appears limited across this part
of the country. Even if a vort max does approach the CWA, an
increase in cloud cover seems more likely than precipitation. In
the absence of any large scale air mass exchanges and with a
steady northerly flow component at the surface, temperatures over
the next several days will tend to moderate slowly towards more
seasonable values with day to day variations largely dependent on
the amount of cloud cover. Precip chances increase marginally
towards the end of the week and into the early part of next



.AVIATION:  (For the 18z TAFs through 18z Monday Afternoon)
Issued at 1241 PM CDT Sun Apr 26 2015

Ridge of high pressure is building across the region. Expect
northeast flow to continue, and remaining MVFR clouds to continue
pushing south/southwest through the afternoon and early evening.
VFR flight conditions are expected to prevail outside of the areas
of lingering clouds this afternoon, and will prevail after the
clouds exit the forecast area.

Specifics for KSTL:

VFR flight conditions and northeast wind will prevail at Lambert
through Monday. Prevailing wind direction will be nearly a direct
crosswind on the main runways. Tried to give the best prevailing
wind direction possible, which looks to be south of 30 degrees for
most of the period through Monday. That being said, occasional
jogs north of 30 degrees look likely through this afternoon.





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