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

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FXUS63 KEAX 251757

1157 AM CST Thu Dec 25 2014

Issued at 342 AM CST THU DEC 25 2014

Water vapor imagery showing deep positively tilted trough digging
along the West Coast this morning with low amplitude ridging
downstream across the Plains and Lower Missouri Vly. Temps this
morning largely residing in the lower 30s...with regional VAD wind
profiles showing a notable increase in recent hrs thanks to a
strengthening pressure gradient across the Nation/s Heartland. As has
been highlighted in recent days...ridging aloft combined with strong
thermal advection will allow for a warm Christmas Day with upper 40s
to lower 50s expected area wide this afternoon. Of concern however
will be the strengthening winds with all available guidance
suggesting sustained winds of 20-25 kts...with higher gusts /30-35 kt
range/later today. Toyed with the idea for a wind advisory across
western sections of the CWA...however have decided to hold off as
best pressure fall couplet expected to move into our region late in
the day. This should allow highest peak heating winds to occur
across the High Plains into central KS...with slightly weaker winds
downstream into our area. Regardless...this Christmas Day promises
to be warm /10-15 degrees above normal/ and breezy.

Next weather feature of interest will arrive by Friday afternoon as a
cold front starts to approach from the northwest. Out ahead of this
boundary...warm air advection and weak isentropic upglide will result
in developing -RA/DZ Friday afternoon...with a continuation right into
Saturday morning. In contrast to last night/s model runs...feature
looks much more progressive which should result in precip exiting
stage right by early Saturday afternoon. What looked like a possible
region wide snowfall is looking less and less ominous this morning as
fcst soundings show very poor moisture aloft in the ice crystal
growth region. That said...cannot rule out some light accumulations
Fri night/early Sat but accums will likely remain well under an

Heading into next week...main story will be the return of very cold
weather following the passage of a cold front Monday
afternoon/night. GFS and ECMWF very much in agreement that an airmass
with origins to northern Canada will dive south across the Plains and
Midwest as high pressure of nearly 1050-mb builds south along Front
Range. With clear skies at night...overnight lows may extend into
the single digits/lower teens Wed and Thurs mornings with highs
struggling to reach the 20 degree mark. As we stated
yesterday...enjoy the warm weather today while you can!


.AVIATION...(For the 18Z TAFS through 18Z Friday Afternoon)
Issued at 1139 AM CST THU DEC 25 2014

VFR conditions will persist through much of the period. Tight
pressure gradient across the region will allow higher momentum winds
to transfer to the surface resulting in gusty surface winds
continuing through the daylight hours. The gradient will relax and
winds decreasing with loss of diurnal heating. Mid and high Clouds
will increase as cold front approaches the terminals by 12Z. MVFR
ceilings will begin to build in by late in the prevailing TAF period
and will be dependent on the timing of the frontal passage.




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