Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 271719

1219 PM CDT Wed May 27 2015

...Update to aviation forecast discussion...

.SHORT TERM...(Today and Tonight)
Issued at 354 AM CDT WED MAY 27 2015

The old upper trough axis was into Missouri at 08Z with at least one
minor wave working its way east into Colorado. Convection continues
to meander east out of eastern Colorado but appears to be on a slow
weakening trend. Weak surface high was centered over southwest
Nebraska with modest south winds to its southwest giving minor aid
to the SW KS precip. Still some mid cloud in the area with nearby
radars showing some lower level mixing behind the old system. Hard
to rule out patchy fog with the ground obviously wet and will

South to southeast winds slowly return today, and with increasing
deep layer moisture, the upstream convection could maintain itself
into the local area late this morning into the early afternoon, but
it will likely outrun support by mid afternoon so have precip
mention limited to western locations today. The next upper wave
meets with the increasing moisture along the High Plains for
convection to re-fire there this afternoon. Overnight 850mb winds
continue from the south but only reach around 20kt, but will likely
be enough to maintain convection into central and eastern Kansas
tonight as PW values reach 1.5". Have kept a mid-range PoP at this
point with uncertainties on location and coverage. The modest inflow
will keep effective shear below 30kt and along with elevated CAPE
peaking around 500 J/kg, severe weather is not anticipated.

.LONG TERM...(Thursday through Tuesday)
Issued at 354 AM CDT WED MAY 27 2015

On Thursday morning southwest flow aloft remains in place with a
plume of steep mid level lapse rates spreading eastward over the
plains. Models are hinting at convection somewhere over western and
central KS early Thursday morning. This complex could linger during
the late morning hours as it most likely weakens. The southwest flow
aloft also supports the lee trough and return flow bringing mid to
upper 60 dew points back to eastern KS. Cape during the day Thursday
could range between 2500-3500 j/kg. The deep layer shear is less
impressive, and should not support any organized severe convection.
This type of environment could poss a marginal risk for large hail
and damaging winds. Most of models develop convection driven by weak
mid level impulses and the lack of CIN, although the low level focus
is not obvious at this point. If convection the previous night
leaves an outflow boundary around it could be the focus if it
doesn`t mix out. There could be a break Thursday night before the
next round of precip arrives along with a cold front passage. This
front will be driven by a shortwave that tracks over the northern
plains and upper Midwest. There are a few timing issues among the
models, but consensus is that the front slides through the area
Friday night. Several shortwaves appear to progress over the
region during the day Friday possibly supporting storms out ahead
of the front in the warm sector. Instability will continue to be
modest although deep layer shear again is not impressive. With the
front south of the area by this weekend drier air and cooler
temperatures could make for pleasant conditions with highs in the
upper 60s to low 70s. Sunday morning could be chilly with low
temperatures ranging from the upper 40s to mid 50s. The region
will then have time to dry out as the pattern begins to relax
through mid week. A mid level ridge builds into the southern
Rockies/plains, and high temperatures rebound back to the 80s.


.AVIATION...(For the 18Z TAFs through 18Z Thursday Afternoon)
Issued at 1217 PM CDT WED MAY 27 2015

Conditions are expected to remain VFR the majority of the period,
until ceilings begin to lower to MVFR late tonight/tomorrow
morning.  There is a large amount of uncertainty with timing and how
far a complex of storms will move east; therefore, have mentioned
VCTS at MHK after 06Z, although TOP/FOE may need to be adjusted with
this mention later.




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