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000
FXUS63 KTOP 252329
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
629 PM CDT Sun Jun 25 2017

...Update to aviation forecast discussion...

.SHORT TERM...(This evening through Monday)
Issued at 304 PM CDT Sun Jun 25 2017

As of 20z, a broad upper level trough was positioned across the
upper midwest. The central and northern plains continue to reside
within the mid level northwest flow. Water vapor reveals a subtle
700MB wave traversing the area, contributing to the scattered
showers and thunderstorms across portions of Kansas. As the wave
exits the area this evening, the bulk of showers will push eastward
of the area. At the surface, a cold front was located along Highway
400. As high pressure and dry air advection continues to build in,
the front will continue to be shunted southward. To the north of
the surface boundary, weak isentropic lift will remain over the
southern counties and may contribute to a few rain showers through
the overnight hours.

Shower and thunderstorm chances will once again increase by
midday on Monday. A secondary embedded wave within the northwest
flow will traverse the central and northern plains, sparking
showers and thunderstorms along a secondary weak surface boundary.
Modest mid level lapse rates (5-6 C/KM) and dew points in the
upper 50s to near 60 will contribute to MUcape between 500 and
1000 J/KG. Effective shear will remain near 30 knots. Due to the
limited instability and shear, the potential for strong to severe
storms appears low. High temperatures tomorrow afternoon will
remain ~10 degrees below normal with highs in the upper 70s.

.LONG TERM...(Monday night through Sunday)
Issued at 304 PM CDT Sun Jun 25 2017

Isolated showers/tstorms may linger into Monday evening but shift
to the west of the area for much of the day on Tuesday, under the
influence of surface high pressure for much of the day. It should
also bring one more day with highs in the low 80s. Southerly winds
return to the boundary layer and the LLJ also returns over the
state Tuesday night, which advects moisture and instability back
into the Central Plains. Strength of the overnight convection
Tuesday night into Wednesday will depend on how much return there
is, and the timing of the northern plains shortwave, but at this
time may see enough instability and shear for some strong storms
in the northern counties.

Front potentially stalls out over eastern Kansas late Wednesday
into early Friday and could remain the focus for repeated rounds
of convection, before the stronger shortwave dislodges it to the
south late Friday. Overall the period is unsettled, with chances
for strong storms, and with potential for repeated rounds of heavy
rainfall. Recent runs of the EC and GFS suggesting front may move
south and west of the area for much of the weekend, but with an
active progressive pattern, timing could certainly change between
now and then.

&&

.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 629 PM CDT Sun Jun 25 2017

VFR conditions are expected through much of the period at the
Terminals. SHRA is expected to remain south of the terminals
through 14Z then focus near or to the north after 17Z. Winds
remain under 10 kts through the period.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Baerg
LONG TERM...67
AVIATION...53