Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 230515

National Weather Service Topeka KS
1215 AM CDT TUE AUG 23 2016

...Update to aviation forecast discussion...

.SHORT TERM...(This Evening through Tuesday)
Issued at 255 PM CDT MON AUG 22 2016

Latest surface analysis shows a surface trough over the Western High
Plains with a retreating surface high over the Ohio Valley. Surface
dew pints int he lower 70s were located across north Texas and into
southern Oklahoma this afternoon. Aloft a upper level low was moving
into Alberta Province while the associated upper trough extended
south into Oregon. Tonight the low level jet will transport moisture
northward into eastern Kansas. Isentropic lift in the 305K to 310K
layer may generate some elevated showers and thunderstorms across
east central Kansas while a weak wave ejecting out of the western
trough may generate an isolated shower or thunderstorm late in the
night across north central Kansas. Clouds will increase after
midnight and some fog is also possible across northeast and east
central Kansas. Not expecting any dense fog as models are in
agreement with the formation of a low level stratus deck of clouds.
The low level jet will veer to the southwest late tonight and early
Tuesday with the lift shifting off into Missouri by mid morning.
Expect a lull in precipitation chances from mid morning until mid
afternoon. By the afternoon a mid level shortwave trough will eject
northeast across Kansas and Nebraska while the main upper low moves
eastward across southern Canada and the Dakotas. This will move a
cold front east and southeast across the Plains and moving it into
central Nebraska and northwest Kansas by late afternoon. Should see
come clearing in the afternoon hours especially out in north central
Kansas. Forecast soundings show mlcape of 1800-2000 J/kg in the
afternoon. 25 to 30 kts of shear is forecast in the late afternoon
hours. Main convection should develop across Nebraska ahead of the
front with more isolated to scattered possible across the CWA. Any
of the stronger storms will be capable of producing hail and damaging
winds. Highs on Tuesday will be in the mid upper 80s with the
warmer reading across north central Kansas.

.LONG TERM...(Tuesday Night through Monday)
Issued at 255 PM CDT MON AUG 22 2016

Tuesday night an upper level wave moves over eastern Nebraska and
portions of northeast Kansas.  While the best dynamics remain north
of the area for this system, CAPE and shear values still do indicate
the potential for strong to severe storms, with the most likely
scenario being storm initiation northwest of the area and a complex
of storms moving into northeast Kansas in the evening.  On
Wednesday, a front makes its way towards the area, bringing more
chances for storms through the afternoon in central Kansas and
moving northeast toward the area by the evening.  Slight
disagreement in models on where the front will hang up Wednesday
evening into Thursday, but overall it looks like widespread amounts
of a half inch to an inch with locally heavier amounts will be
possible during this time frame.

The front looks to move southeast of the area Thursday evening into
Friday, which could very well lead to a dry conditions for the area
Thursday afternoon and evening.  By Friday, Kansas will be in between
surface high pressure to the northeast and a surface trough over the
Rockies.  Southwest to northeast upper level flow over the Central
Plains exists through Sunday afternoon with a number of shortwaves
moving through the mean flow.  This keeps precipitation chances
through the end of the period.  Models tend to diverge on the
overall synoptic pattern by late Sunday, but an upper level trough
may clip the area by Sunday night or Monday.

As for temperatures, Wednesday warms into the upper 80s before the
front moves through Thursday creating a gradient across the area
with highs in the mid 70s in north central Kansas.  From here a
gradual warm up will be seen from Friday through the weekend with
highs back to the upper 80s by Monday.  Lows will generally be in
the 60s through the period.


.AVIATION...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1205 AM CDT TUE AUG 23 2016

VFR conditions through the first several hours of the TAF, but low
stratus is developing in Oklahoma and will stream north toward
local TAF sites. Expect it to come in as IFR for 1-3 hours before
lifting to MVFR by around 14Z and then lifting and eventually
scattering by around 18Z. Scattered thunderstorms will develop
between 14Z and 21Z but are more likely to stay east of TAF sites,
although may come close to TOP/FOE during that time frame.


.TOP Watches/Warnings/Advisories...


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