000
FXUS63 KEAX 191112
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
612 AM CDT Sun May 19 2013

.SHORT TERM...(Today and Tonight)
Issued at 338 AM CDT SUN MAY 19 2013

Main concern in the short term revolves around the potential for all
modes of severe weather late Sunday afternoon through Sunday night
as well as the potential for a second round of severe weather on
Monday.

A broad, slightly negatively-tilted upper level trough is moving
through the eastern Rockies this morning. This trough will move out
into the northern Plains today with an upper level low developing
across South Dakota. However, a lead wave in the base of the trough
will rotate into the Central Plains by tomorrow afternoon. This will
force a stout cold front into eastern Kansas. As this wave over
takes the front this should allow for initiation during the late
afternoon across eastern Kansas. Model soundings show that when
storms initiate there will be a very moist environment to work with
as dewpoints will be in the upper 60s to near 70. Also, there will
be steep lapses rates across the region as well as CAPE values of
2000-3000J/kg. So, the ingredients are there for severe weather
however the caveat will be if early morning convection across
central and southeastern Kansas continues to lift northeastward this
could led to increased cloud cover and may not allow the
environment to recover and realize that potential instability. That
being said if cloud cover does break and we do realize the forecast
highs of the mid 80s tomorrow there is a good potential for severe
weather. Models in good agreement in trying to develop supercells
across eastern Kansas during the late afternoon tomorrow. Early in
the evolution of these storm all modes, large hail, damaging winds
and even an isolated tornado will be possible. As these storms move
eastward into the western CWA they will begin to form a line of
storms as which point the main threats would then become large hail
and damaging winds. This line of storms is then expected to move
eastward across the entire CWA tomorrow night.

The severe weather potential on Monday becomes even more uncertain
based on whether the environment can recover during the afternoon
hours. The set up however is similar to Sunday only with a slight
shift south and east to severe potential. the upper level low will
continue to rotate across South Dakota and northern Nebraska. A
secondary cold front will develop across the Plains states early
Monday and shift eastward into eastern Kansas by Monday evening.
Again, conditions will be favorable for severe weather with steep
mid level lapse rates, dewpoints in the mid 60s, and CAPE values
between 2500-3500J/kg. Also, of interest is models show a jet streak
moving through the area Monday evening which would aid in supercell
development with again all three mode of severe weather possible.

.LONG TERM...(Monday through Saturday)
Issued at 338 AM CDT SUN MAY 19 2013

Monday night into Tuesday...Convection will be ongoing Monday night
across the CWA with strong to severe weather possible as discussed
during the short term. Thunderstorms will gradually shift east of
the area by Tuesday morning. The upper low will only make slow
progress eastward, with the surface cold front located from north
central to southwest Missouri by Tuesday afternoon. Another round of
thunderstorms will be possible along and east of the boundary
Tuesday afternoon and evening. Severe weather will once again be
possible, mainly in the eastern quarter of the CWA. Thereafter, the
front is expected to clear the area by Tuesday night, ending chances
for precipitation. The front will sag southward and stall near
southern Missouri into south central Kansas by Wednesday into the
end of the work week. Likewise, slight chances of showers and
thunderstorms will be possible mainly across southern sections of
the CWA through Friday, in areas closest to the frontal boundary.
Near seasonal temperatures can be expected through the period, with
highs in the 70s and lows in the 50s.

&&

.AVIATION...(For the 12Z TAFS through 12Z Monday Morning)
Issued at 611 AM CDT SUN MAY 19 2013

An area of rain with embedded thunder was moving toward western
Missouri this morning and should arrive at all terminals by the time
the forecast becomes valid. Cloud bases are fairly high with this
area so other than a period of rain do not expect there to be much in
the way of impacts at the terminals. This rain should dissipate by
mid morning with clouds beginning to thin out by this afternoon. This
will allow for a very unstable airmass to develop across eastern
Kansas and western Missouri setting the stage for severe
thunderstorms at all terminals late this afternoon and this evening.
The most likely timing into STJ, MCI, and MKC looks to be between
00Z and 04Z with conditions improving after this time frame.

&&

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

$$

SHORT TERM...73
LONG TERM...Blair
AVIATION...CDB