Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 130815

Area Forecast Discussion
National Weather Service Topeka KS
315 AM CDT Wed Sep 13 2017

.SHORT TERM...(Today and tonight)
Issued at 314 AM CDT Wed Sep 13 2017

Weather pattern starts to transition to a warmer one today, as the
now extratropical remnants of Irma slowly lift to the east
northeast, while a shortwave ridge moves overhead and the surface
lee trof returns to the high plains.  While the western counties
will switch around to southerly winds and mix into slightly higher
temperatures than today into the upper 80s to near 90, the eastern
counties may get one more day in the low to middle 80s as the warmer
temps aloft move eastward later in the day.  Some guidance
suggesting a slight chance for some precip in the western counties
late in the afternoon, but if this occurs think it will be later
after midnight as isentropic lift tightens and better lift moves
overhead. Lows tonight fall into the lower 60s.

.LONG TERM...(Thursday through Tuesday)
Issued at 314 AM CDT Wed Sep 13 2017

Decent isentropic upglide ahead of the upper wave may linger a few
showers and thunderstorms on Thursday morning across north central
areas. Expect these to dissipate with skies becoming mostly sunny by
the afternoon. With the sfc trough deepening eastward over NE,
pressure gradient ramps up over northeast KS, inducing wind speed in
excess of 20 kts during the afternoon hours. Wind gusts up to 35 mph
may be possible. Forecast soundings show deep mixing of the boundary
layer paired with the strong dry advection to drop RH values into
the middle 20s. Fuels are beginning to show gradually drying over
north central areas, with the potential for elevated fire danger
Thursday afternoon.

Dewpoint temps surge into the middle 60s by Friday, tempering the
fire weather threat despite the strong southerly winds continuing
through Saturday. Highs during this period are likely to reach the
lower 90s, around 10 degrees above normal for this time of year.
As the main upper trough swings northeast through the northern
plains Saturday afternoon, the cold front surges southeast into the
area, sparking scattered showers and thunderstorms through the
evening. Effective shear still appears pretty marginal around 20 kts
so not anticipating organized severe weather with this system.

Still some inconsistencies thereafter between guidance however it
does appear the front hangs up across the region, resulting in off
and on thunderstorms through the beginning of next week. West to
southwesterly flow aloft may spell for the active weather pattern
continuing through next week.


.AVIATION...(For the 06Z TAFS through 06Z Thursday)
Issued at 1129 PM CDT Tue Sep 12 2017

Apparently there will be some shallow ground fog at TOP based on
the 0408Z SPECI. I expect this to be temporary as forecast
soundings show the moisture to be extremely shallow and none of
the MOS guidance is picking up on the ground fog. Otherwise a
relatively dry airmass and lack of organized forcing should allow
VFR conditions to persist.




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