Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 241117

617 AM CDT Fri Oct 24 2014

...Update to aviation forecast discussion...

.SHORT TERM...(Today and Tonight)
Issued at 346 AM CDT FRI OCT 24 2014

A mix of low clouds, cirrus, haze and fog over the area early this
morning, keeping overnight lows in the 50s.  Current surface winds
out of the south , with 925 winds slowly turning south southwest.

As ridge aloft noses eastward through today, 850mb temperatures of
20C move over the western half of the forecast area.  With a mix
just below this level, high temperatures would reach toward middle
80s west with slightly cooler highs in the upper 70s to low 80s
toward the east.  High pressure slides across the northern plains,
leaving a weakness in the wind fields over the Topeka forecast area
in the early morning hours on Sunday.  Soundings would suggest a
good chance for fog in the major river valleys and adjacent plains,
and likely southeast through the Flint Hills where moisture has a
chance to pool before winds become light and the skies clear leading
to strong inversions.  Anticipate overnight lows in the 50s mainly
along and south of I70 where this occurs, and left fog chances out
across the far northwest as cooler drier air moves in that area.

.LONG TERM...(Saturday through Thursday)
Issued at 346 AM CDT FRI OCT 24 2014

By Saturday morning upper ridge continues to build into the southern
plains leading to the persistently warm mid level temps. There are
indications that if ground fog forms it could linger for an hour
or so after sunrise. Soundings still show that daytime mixing on
Saturday is rather shallow under 900 mb, which will keep the highs
in the low to mid 80s. The only exception would be far northeast KS
where temps might only reach the upper 70s. On Sunday the mid/upper
level trough approaches the northern plains keeping the area under
deep southwest flow. This will set the stage for windy conditions
during the day Sunday with gusts up to 30 mph especially along and
east of the turnpike. High temps on Sunday expected to be similar to
Saturday in the low to mid 80s again.

That mid/upper level system continues to progress towards the Great
Lakes region, which will drag a cold front through the central
plains. The airmass behind this front appears to be more seasonal as
we head into next week. The front is due to arrive during the day
Monday, but the chances for precip have trended downward. Soundings
during this time frame show that warm mid level temps will keep the
capping inversion in place despite decent 850 mb moisture advection.
Even post frontal rain seems unlikely at this point as dry air
begins to take over, and the lift focuses further east. Surface high
pressure quickly slides across the region behind the system giving
way to return flow. Temperatures will be more seasonal through mid
week with highs in the 60s and lows in the 40s.


.AVIATION...(For the 12Z TAFs through 12Z Saturday Morning)
Issued at 615 AM CDT FRI OCT 24 2014

Enough mixing in the low levels to keep fog mainly at bay, with
lower stratus moving off to the east of the TAF sites at this
hour. Later this morning visibility will improve to VFR and
continue through the day and evening. Early Saturday morning may
see a return of fog, but will give another issuance before making
mention that late in the forecast period.




LONG TERM...Sanders
AVIATION...67 is the U.S. government's official web portal to all federal, state and local government web resources and services.