Area Forecast Discussion
Issued by NWS Kansas City/Pleasant Hill, MO

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FXUS63 KEAX 211749

National Weather Service Kansas City/Pleasant Hill MO
1149 AM CST Sun Jan 21 2018

Issued at 321 AM CST SUN JAN 21 2018

Water vapor imagery showing large upper low across the Desert
Southwest this morning, with nighttime microphysics channel
highlighting an abundance of low clouds across the lower Missouri
Vly in a well-established warm air and moisture advection regime.
Quick look at latest observations reveals warming temperatures
this morning, setting the stage for what should be a warm
afternoon with high temps likely topping out in the lower 60s
across much of the area. Periods of light drizzle will remain
possible today, before precipitation grows more upscale in
coverage and intensity this evening and overnight as main cold
front approaches from the west. Fcst models continue to hint at
weak instability immediately ahead of this feature, with the
consensus suggesting MLCAPE values ranging from 100-400 J/kg later
this afternoon and evening. Quick look at area fcst soundings
shows a weak capping inversion persisting through the afternoon
before increasing lift and the arrival of cooler temps aloft allow
for gradual cap erosion. With a tall skinny CAPE appearance on
area soundings, main isolated gusty winds cannot be ruled out with
any developing storm activity, especially east of Route 65.

Following fropa later this evening, a well-pronounced dryslot will
work into the area which should lead to a reduction in
precipitation coverage. After 12z Monday, dryslot is forecast to
move off to the east while moisture associated with a decaying
deformation zone slides over the area. Temperatures should support
snow when this occurs, however very light QPF values should keep
any snow accumulation fairly minimal across the board. Otherwise,
Monday will be characterized by brisk northwest winds as cold air
advection temporarily dominates the local weather pattern.

Beyond this, northwest flow to dominate through midweek with
seasonal temperatures persisting. By Thursday, next Pacific
disturbance to begin working on the West Coast with a pattern
shift towards southwest flow expected downstream across the
Central U.S. This will set the stage for another nice warming
trend with low to mid 50s possible both Thursday and Friday. This
will be fairly short lived however as this feature slides east
and brings the next chance for precip and cooler temperatures to
the area by next weekend.


.Aviation...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 1146 AM CST SUN JAN 21 2018

Forecast kicks off with inconsistent low ceilings across the
area, prompting a TEMPO group for brief improvements in ceiling
during an overarching period of MVFR stratus. Shower/T-storm
coverage this evening and tonight will be spotty at best, so
decided to avoid mention of any prevailing rain at the terminals,
considering any period of rain should be brief. Early Monday
morning is a bit muddier once the deformation band comes through.
Could be some light drizzle, although certainty is low considering
mixed model guidance. The higher probabilities of reduced VIS
should be just to the north of MCI. Went ahead with an agressive
MVFR forecast for now, but could back off it or accelerate it
depending on the how the next 12 hours look.




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