Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 261728

Area Forecast Discussion
National Weather Service Topeka KS
1228 PM CDT Fri May 26 2017

...Update to aviation forecast discussion...

.SHORT TERM...(Today and tonight)
Issued at 325 AM CDT Fri May 26 2017

Area of convection carrying over from strong storms in western
Kansas exiting eastern Kansas early this morning. Strongest storms
appear to be on the edge of the steepest lapse rates in decent
elevated moisture advection. Weaker convection moving off the Front
range as well but also much weaker support for persistence in this
area today. Recent observations put surface low pressure over
northwest Oklahoma with upper flow becoming more zonal.

Thunderstorm chances continue to be the main forecast challenge
through tonight. Models are in quite good agreement with overall
trends with surface low weakening but leaving a weak trough over the
far southeastern counties through the day. Moisture pooling along
the boundary brings ML CAPE values to around 2000 J/kg, but some CIN
remains with convergence along the boundary rather weak. Hard to
completely rule out any storm from forming, but chances look too low
for a mention. If a storm would fire, hail and wind would be the
main concerns. Attention then turns to the west with a weak wave
interacting with regionally-high moisture content for convection to
builds east across northern Kansas through the night. Have gone a
bit more robust in coverage than model depictions to err on the side
of caution but southeastern areas will likely stay dry. Elevated
CAPE and at decent low level jet could support some risk for large

.LONG TERM...(Saturday through Thursday)
Issued at 325 AM CDT Fri May 26 2017

Storm coverage and chances for Saturday will hinge in part on how
the MCS that is progged to move along the KS/NE border progresses,
where the outflow ends up, and how fast the front pushes southward
behind the larger scale upper shortwave trof pushing southward into
the southern plains. Instability builds considerably along and south
of this boundary, so its location will have an impact on modes and
threat for severe weather.  Area is currently in a slight risk by
SPC with greater threat emphasized just to our south.

This looks to leave dry weather for Sunday and Monday for the
holiday weekend and into mid week as the state remains under
northwestelry flow aloft.  Flow begins to flatten by later Wednesday
with next trof moving into the southwestern states late in the week.
Daytime highs through the period lie in the upper 70s to near 80,
with overnight lows generally in the 50s.  Rain chances return
Wednesday afternoon through the late week.


.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1228 PM CDT Fri May 26 2017

VFR conditions are expected through 12Z then mvfr cigs as stratus
develops through 15Z. Winds north near or less than 10 kts then
back through the night to the east by 15Z. Models differ on speed
and placement of convection tonight and confidence is not high
enough to add to the terminals at this time.




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