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

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FXUS63 KEAX 190602

1202 AM CST Wed Nov 19 2014

.SHORT TERM...(This Evening through Thursday Night)
Issued at 342 PM CST TUE NOV 18 2014

Will finally see the mean upper trough axis shift east over the next
few days leading to a pattern change, as well as an end to our mid-
Winter like temperatures, by Friday. Satellite imagery does show a
shortwave trough that is streaking through SD/NE. Feature is moisture
starved but an associated cold front will sweep through the CWA after
midnight. Fortunately, the bulk of the cold air advection will miss
us and head towards the Great Lakes.

Finally made it above freezing this afternoon. Almost forgot what
that felt like. Southwesterly winds will continue overnight and
result in a non-diurnal temperature curve. Northern portion of CWA
may struggle to warm within the post-frontal air mass due to the weak
cold air advection but more likely if a stratocumulus layer forms as
advertised by the last several model runs of the NAM. Am not
completely sold on the NAM thus only went with broken cloud cover.
Should thicker cloud cover occur flurries will be possible as BUFR
soundings show ice crystals would be possible. Coupled with a steep
low-level lapse rate convective snow showers could form. Main
detriment would be the lack of any mid level vorticity lobe moving

Weak high pressure will shift through the CWA on Thursday with
temperatures slightly warmer than Wednesday, albeit still 15
degrees below average. While no precipitation is expected
some moisture/thin layer of clouds could be trapped just under the
mid level warm advection nose and thus keep the CWA out of a mostly
sunny forecast. Uncertainty on this precludes any adjustment to the
model blend for high temperatures.

By Thursday night the warm advection above the boundary layer will
be strengthening in advance of a weak shortwave approaching from the
southwest. Northward transport of low-level moisture over a
developing inverted surface trough coupled with the warm air
advection around h8 and a shallow cold pool aided by easterly
boundary layer winds will increase the threat for patchy freezing
drizzle after midnight.

.LONG TERM...(Friday through Tuesday)
Issued at 342 PM CST TUE NOV 18 2014

The potential for freezing drizzle will continue into Friday morning
as warm, saturated near-surface air continues to glide up over
ground temperatures in the mid to upper 20s. Models differ a bit in
how early the moisture arrives, so the forecast will need more
refinement as they converge on a solution -- but the potential for a
light glaze of ice will exist through at least 15-16z on Friday
morning, until temperatures warm above freezing.

Moisture will continue to stream into the region ahead of two
approaching systems; one that will lift out of the desert Southwest
and the other which is expected to swing down into the Plains states
from the Pacific NW.  Rain showers are expected to become more
likely and more widespread on Friday night and especially Saturday,
then will begin to taper off as the cold front associated with the
NW system pushes through on Sunday. A few light snow showers are
possible on the back side of the system late Sunday night or Monday,
but little to no accumulation is expected with most moisture exiting
the region before the arrival of the cold air, and previously
warm/wet ground will limit accumulation.

More notable than the rain, perhaps, will be the temperatures that
accompany the southern system this weekend. Highs are expected to
reach the lower to possibly mid 50s both Friday and Saturday even
despite the increase in cloud cover, which will be quite a deviation
from the previous ~10 days of below normal temperatures. Lows will
be several degrees above normal in the 30s and 40s this weekend due
to the cloud cover and WAA throughout the region. The colder air
that filters in behind the NW system will likely knock the region
back into the 30s or perhaps upper 20s for a few days, but for now
does not look nearly as persistent as our current cold pattern.


.AVIATION...(For the 06Z TAFS through 06Z Wednesday Night)
Issued at 1159 PM CST TUE NOV 18 2014

Still looking at VFR conditions through the next 24 hours. Forecast
soundings still want to hint at some MVFR cigs with passing snow
flurries. Expect that MVFR deck to be SCT with perhaps some brief
periods of BKN MVFR CIGs. Do not expect the snow flurry activity to
cause restrictions. Also, well mixed low level environment looks to
be favorable for some gusty winds once FroPa occurs, then dwindling
after sunset.




LONG TERM...Laflin
AVIATION...Leighton is the U.S. government's official web portal to all federal, state and local government web resources and services.