480 
FXUS63 KEAX 201740
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
1140 AM CST Thu Feb 20 2014

.UPDATE...
Issued at 1001 AM CST THU FEB 20 2014

Latest model data and trends from radar indicate that north central
to northeast Missouri will likely be spared from widespread rains
that could induce flooding. Therefore have dropped the Flood Watch
for that was still in effect for that section of the forecast area.
Shower and thunderstorm activity will remain focused more across
northeast Kansas and northwest Missouri this morning where a
combination of rain, changing to sleet and snow, will occur through
the early afternoon hours. Snowfall totals in far northwest Missouri
remain very difficult to forecast owing to the fact that surface
temperatures are currently, and are expected to remain, above
freezing through much of the daylight hours while its precipitating.
But, the dynamics of the deformation band aloft still look sufficient
to put down a couple quick inches of slushy accumulations from
Maryville south through St Joseph and possibly into the far northern
side of Kansas City...and as far east as Interstate 35.

&&

.SHORT TERM...(Today and Tonight)
Issued at 430 AM CST THU FEB 20 2014

At the surface a very strong trough has formed on the eastern side 
of the Rocky mountains, and currently sits over SC/SE Kansas. The 
surface pressure gradient associated with this very strong trough 
will cause southerly winds to pick up on the eastern edge to around 
20 to 30 mph with gusts approaching 40 mph later today. An evident 
surface warm front currently sits along Interstate 70, and is 
characterized by temperatures in the 30s to lower 40s north of the 
boundary to temperatures well in the 50s to lower 60s in the warm 
sector south of the boundary. Thunderstorms are currently forming 
along along the advancing warm front and will have plenty of 
instability to grow upscale into strong thunderstorms. This activity 
is generally forming along a strong low level jet which is currently 
nosing into western Missouri, and is characterized by strong 850 
winds between 50 and 60 kts. Effective bulk shear is between 40 and 
50 kts, and given strong MU elevated CAPE of around 1000 J/kg the 
ingredients are in place for these storms to be strong to marginally 
severe. As the morning progresses HRRR indicates that these storms 
will form a line spanning west to east just north of Interstate 70, 
and will lift north through the day. Expect the bulk of the strong 
thunderstorm potential to move northward into Iowa by around 10 am. 

The focus then shifts to the late morning and afternoon hours, when 
areas of far northwestern Missouri could experience a period of 
moderate to heavy snow. The main mid level trough, which currently 
sits over the High Plains will swing through the area later this 
afternoon. Southern and Central Missouri will likely see a down tick 
in precipitation coverage as the systems dry slot races through 
southern and central Missouri. Across northern Missouri large scale 
ascent associated with the mid level trough will bring another round 
of precipitation later this morning. The aforementioned surface 
trough will continue eastward, and behind the departing trough cold 
northwest winds will crash into the area causing the thermal profile 
to cool very quickly. By mid morning the thermal profile along 
northern Missouri will be cooled adequately for snow production. 
Very strong low/mid level frontogenesis in northern Missouri, as 
well as some negative EPV will enhance the lift associated with the 
mid level wave. All told there could be up to 15 to 20 -ubar of 
Omega this morning and this afternoon contributing to rather 
efficient snow production. While cold air will rush in surface 
temperatures will struggle to drop below freezing, so any snow 
production and accumulation may be mitigated by the warmer surface 
temperatures. Went with a general 10-12:1 snow ratio to attain a 
final figure of around 2 to 4 inches of snow accumulation for the 
far NW corner of Missouri, with decreasing amounts toward the east 
and south. Concurrent to the snow will be strong northwest winds, 
which will race in as the surface pressure gradient behind the 
departing trough moves through the area this afternoon. Expect the 
winds to be sustained out of the northwest around 30 to 40 mph, with 
gusts perhaps exceeding 50 mph. The strong winds and period of 
moderate to heavy snow will cause visibility to decrease through the 
day. Expect the period of snowfall to be rather brief as the overall 
system quickly glides off to the northeast. By mid afternoon expect 
the bulk of the precipitation to be off to the north, with perhaps 
some lingering rain/snow through the evening.

Model soundings indicate that the low levels could stay well mixed 
through the evening and into the overnight hours, which would allow 
the strong wind gusts to continue at least into the evening and 
perhaps into the overnight hours before gradually dissipating early 
Friday morning.

.LONG TERM...(Friday through Wednesday)
Issued at 430 AM CST THU FEB 20 2014

A return to a West Coast blocking pattern, similar to what prevailed 
through much of January, will send us back into a cold and dry 
pattern by early next week. Primary cold front will drop into the 
forecast area Friday night with a reinforcing shot of cold air 
arriving Sunday. Temperatures in this pattern won't be near as cold 
as they were back in January, but still about 10 degrees below 
average with highs in the 20s and 30s and lows in the teens and 20s 
for much of next week. Could see some light snow Monday and Monday 
night with a broad upper impulse tracking through the Upper Midwest 
but better chances will be to our north.

&&

.AVIATION...(For the 18Z TAFS through 18Z Friday Afternoon)
Issued at 1139 AM CST THU FEB 20 2014

Most of the thunderstorm activity cleared the terminals by the late
morning hours, and while a few more showers and isolated
thunderstorms may be possible any of that activity will likely occur
to the east of our locations. Now waiting for a band of rain, sleet
and snow to move across western Missouri this afternoon. Conditions
should be a bit worse the farther north you go, but with above
freezing surface temperatures prevailing precipitation type will be
hard to pin down. Otherwise, strong and gusty northwest winds will
persist through the rest of the daylight hours diminishing this
evening as they back to the west. The decrease in wind speed should
accompany VFR conditions.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY until 9 PM CST this evening FOR KSZ025-057-060-
     102>105.

     WINTER WEATHER ADVISORY until 3 PM CST this afternoon FOR KSZ025-
     102.

MO...WIND ADVISORY until 9 PM CST this evening FOR MOZ001>005-011>014-
     020>022-028>031-037>040-043>046-053-054.

     WINTER WEATHER ADVISORY until 3 PM CST this afternoon FOR 
     MOZ001>005-011>013-020.

     WIND ADVISORY until Midnight CST tonight FOR MOZ006>008-015>017-
     023>025-032-033.

&&

$$

UPDATE...Cutter
SHORT TERM...Leighton
LONG TERM...Hawblitzel
AVIATION...Cutter