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Area forecast discussion...updated aviation 
National Weather Service St Louis MO
530 PM CST sun Dec 28 2014

Short term: (through late tonight)
issued at 240 PM CST sun Dec 28 2014

Back edge of clouds moving through stl Metro area as of 20z. So will
continue to see clouds move out of region by early this evening.
Otherwise, weak ridge to build in with light and variable winds.
Lows will be in the low to mid 20s.

Byrd

Long term: (monday through next sunday)
issued at 240 PM CST sun Dec 28 2014

Ahead of reinforcing shot of cold air, will see several
shortwaves undercut ridge and slide east through region. Clouds to
be on the increase on Monday with flurries possible Monday night
through early Tuesday. Then Arctic airmass to push south across
region Monday night through Wednesday. Coldest period will be
Tuesday night/Wednesday. Lows Tuesday night will be in the single
digits/upper teens and highs on Wednesday will only be in the upper
teens to upper 20s.

Surface ridge then weakens and slides off to the southeast
allowing temperatures to begin moderating for the last part of the
week and into next weekend. Highs by Saturday will be near normal
in the mid 30s to mid 40s.

In the meantime, extended models have timing and placement
differences with next weather system. Cutoff low that will be over
southwestern US by Thursday will slide east then lift northeast
into region Friday night/Saturday. 12z GFS run is now faster,
deeper and further north with this system then 12z European model (ecmwf). For now
will go with a blend of the two solutions. Precipitation is still
expected to develop and move in beginning Thursday night. The
precipitation threat will expand on Friday and Friday night as warm air advection
intensifies and large scale lift ramps up with the approach of the
upper system. With it being a warmer solution, will keep mention
of wintry mix throughout the event until models come into better
agreement. Will see dry weather return by Saturday night and
Sunday.

Byrd

&&

Aviation: (for the 00z tafs through 00z Monday evening)
issued at 523 PM CST sun Dec 28 2014

VFR and dry conditions expected thru the period. There is some
question of fog development overnight, mainly at sus and cou where
light winds and a clear sky will be in place. However, attm,
believe that any fog development will be patchy and will not
mention in taf. Otherwise, winds will become nely to Ely on Mon
and remain aob 8 kts.

Specifics for kstl: VFR and dry expected thru the taf period.
Light and vrb winds tonight will become nely on Mon and remain aob
8 kts.

Tilly

&&

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

$$

Weather forecast office lsx

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