245 
FXUS63 KEAX 111948
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
248 PM CDT Sun May 11 2014

.DISCUSSION...
Issued at 248 PM CDT SUN MAY 11 2014

Main concern for this afternoon and evening will be possible 
convective initiation across northeast KS and northwest Missouri 
along a weak outflow boundary which at 1 PM stretched from Manhattan
KS through Platte City MO to Unionville MO. Cumulus has started to
become more enhanced along this boundary, and it could serve as a
focus for convective initiation with in the next few hours. A fairly
stout capping inversion was still present on KTOP's 18z sounding and
at least some cap is evident in the cu field; however, model
soundings suggest that the cap may be slightly weaker to the north,
and could weaken slightly with additional surface heating. 0-3 km
helicity in the 200-300 range, 0-6 km shear in excess of 40 kts, and
MUCAPE values in the 2000-2500 J/kg range are all supportive of
supercell structures producing large hail and damaging winds if
storms do develop, and CAPE values may also increase during the
afternoon as surface heating continues. Local enhancement of low-
level wind shear and vertical vorticity along the boundary may also
support isolated tornadoes this afternoon into the early evening for
any storms that develop and track along the boundary; however, little
to no wind shift or temperature discontinuity is currently evident
with the outflow boundary, possibly lowering the impact it could have
on existing storms. Any severe threat will be confined to areas along
and north of the outflow boundary which may also lift slightly north
during the afternoon, and the remainder of the area to the south and
east should remain capped in the warm sector through the afternoon
and evening, including the KC metro area. Additionally, Bunker's
right moving-supercell vectors are to the east northeast, which
should keep any storms that develop north of the CWA out of the area.

Storms which develop along the main warm front in southern Iowa, 
southeast Nebraska, and north central - northeast Kansas this 
afternoon and evening are expected to stay close to the boundary due
to the east-northeast supercell storm motion; however, a few storms
could throw out an outflow boundary and either propagate off the boundary
or result in additional development that could impact far northwest
and northern Missouri late this evening. The front will eventually
begin to make southeastward progress, possibly encouraging any
ongoing storms to begin tracking southeast into the northwestern
corner of the forecast area late tonight into early Monday morning.
These storms should not maintain a tornadic threat as the surface
cools and storms move off the boundary; however, the large hail and
damaging wind threat will continue into the early morning hours
across northwest Missouri and northeast Kansas.

By Monday morning, the strongest activity is expected to lift
northeast into Iowa, and precipitation may briefly end across the
forecast area. Storms will likely re-form along the boundary as it
pushes southward as a cold front by early Monday afternoon, but the
overall severe risk is fairly marginal with lower deep layer shear
and CAPE values, very marginal 0-1 km shear, and 0-6 km shear vectors
oriented parallel to the front. An inch to perhaps two inches of
rainfall is possible through Monday night, and storms should move
southeast quickly enough to avoid any widespread flooding.
Precipitation is expected to push out of the area Monday night or
early Tuesday morning.

Behind the front, cooler temperatures and a few bouts of light rain 
showers are anticipated through the rest of the week. No additional 
severe weather is expected through the end of the period.


&&

.AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 100 PM CDT SUN MAY 11 2014

Mainly VFR conditions are expected across the area this afternoon and
this evening, with the exception of far northwest Missouri and
northeast Kansas where isolated strong to severe thunderstorms are
expected this afternoon. South southeast winds will remain sustained
at 15 to 20 kts with gusts to 30 kts through evening, then will
decrease slightly but maintain gusts up to 20 kts overnight. Storms
will edge into the area overnight into Monday morning, and are
expected to impact TAF sites beginning between 12z-15z and continuing
through the end of the TAF period.


&&

.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&

$$

DISCUSSION...Laflin
AVIATION...Laflin