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Area forecast discussion 
National Weather Service Kansas City/Pleasant Hill MO
508 PM CST Thu Feb 26 2015

Discussion...
issued at 344 PM CST Thursday Feb 26 2015

Cold is the main concern for the next 36 hours with a deep 1042 mb
high building in from the north. Light winds and clear skies
associated this feature should allow temperatures to drop a few
degrees below zero, especially where snow is on the ground over
northern Missouri. Elsewhere temperatures will bottom out a few
degrees above zero. Wind chills across the Macon and Kirksville areas
may get near or slightly below -15 early Friday morning. While this
is typically our criteria for a Wind Chill Advisory, these areas have
seen plenty of nights with wind chills this cold this winter, so they
were left out of any Wind Chill Advisory to match up with offices to
the northeast where criteria is a bit lower.

Confidence continues to increase for accumulating snow Saturday and
Saturday night, as most models have come into agreement on a wide
swath of 3" to 6" across much of the forecast area. The primary
forcing mechanisms with this system, deep isentropic/synoptic-scale
ascent, are typically better resolved by models and more widespread
than some of the more smaller-scale features that have driven many
of the more recent events. This gives more wiggle room in case models
change track or intensity, so confidence is higher for saturday's
event than it has been with some of the other systems we've dealt
with lately. No watch will be issued at this time since snow amounts
should be generally under 6" through late Saturday night.

Sunday is more of a question mark with most models now suggesting
another round of snow with generally an inch or less of accumulation.
This second round would develop as a more narrow band since it
will be driven by frontal dynamics in the vicinity of a stalled
elevated boundary. This type of mesoscale forcing can be tricky for
models to resolve, especially this far out, so confidence is quite a
bit lower for Sunday. Taking an average of model solutions would
favor an inch or so along a 30- to 50-mile-wide corridor somewhere
near or south of I-70. This is the preferred solution at this time,
although it's Worth noting the GFS has been a bit persistent in
bringing stronger ageostrophic forcing and higher precipitation
amounts to a narrow corridor near or just south of I-70. This is
something to watch in case other models decide to hop on board this
solution, in which case a Winter Storm Warning could be needed for
some areas.

Another round of widespread precipitation will move across the area
Monday and Monday night, although this is looking more and more like
rain with developing consensus that the primary surface low will
track to our north. There could be some periods of freezing rain or
sleet Monday morning if this precipitation arrives before
temperatures have time to rise above freezing, but significant icing
doesn't look to be a concern at this time. Total rainfall amounts
with this round could reach between a half inch and an inch for many
locations.

Tuesday/Tuesday night could bring a bit of light snow to the region
as this system departs to the east, otherwise the forecast looks to
quiet down as we head into the middle of next week.

&&

Aviation...(for the 00z tafs through 00z Friday evening)
issued at 508 PM CST Thursday Feb 26 2015

VFR conditions are expected to persist through the forecast period.
Sustained north winds at around 10 to 12 kts will continue through
the next few hours, then will begin to diminish and gradually turn
to the east after 06z. Light east to southeast winds are expected
Friday, along the with continued clear skies.

&&

Eax watches/warnings/advisories...
Kansas...none.
MO...none.
&&

$$

Discussion...hawblitzel
aviation...Laflin

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