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Area forecast discussion...updated aviation 
National Weather Service St Louis MO
532 am 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 County Warning Area 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.

Kanofsky

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
California/Arizona border is forecast to close off as it slowly progresses
eastward over the next few days, likely passing south of the County Warning Area.
It is possible that the extreme southern County Warning Area 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
weekend.

Kanofsky

&&

Aviation: (for the 12z tafs through 12z Monday morning)
issued at 448 am CDT sun Apr 26 2015

The stratus clouds were clearing out across parts of northeast MO
and west central Illinois early this morning as nely winds were bringing
drier air into the region. This clearing line will continue to
progress southwestward this morning with the MVFR, low level cloud
ceiling in cou and the St Louis Metro area slowly rising and
eventually scattering out later this morning. Little if any
cloudiness is expected this afternoon and tonight, maybe a little
cirrus with subsidence across the area as the surface ridge
centered over Minnesota and WI builds southward into the region. Nely
surface winds will continue through the period becoming quite light
later tonight.

Specifics for kstl: MVFR cigs along with patchy light fog and
drizzle can be expected early this morning with the cloud ceiling
rising and eventually scattering out around 15z this morning.
Little if any cloudiness is expected from this afternoon through
Monday morning, except a little cirrus clouds. Nely surface wind
will continue today, becoming light by late tonight, then increasing
again Monday morning.

Gks

&&

Lsx watches/warnings/advisories:
MO...none.
Illinois...none.
&&

$$

Weather forecast office lsx

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