Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 270443

1142 PM CDT Sat Jul 26 2014

...Update to aviation forecast discussion...

.SHORT TERM...(This Evening through Sunday)
Issued at 329 PM CDT SAT JUL 26 2014

Upper ridge continues to be displaced to the south of the hot
airmass, causing forecast difficulties. Upper wave/MCV rotating
around the ridge brought scattered light precip to much of the area
into the early afternoon, with isolated high-based showers
continuing for a few locations near I-35, close to what was
anticipated in yesterday`s forecast. To the north, vigorous
convection has slowly weakened as it comes into the warmer temps
aloft, but is getting into a more unstable airmass.

Hard to get too excited about precipitation chances tonight. Believe
the convection to the north may increase a bit in the next couple
hours, but will be reaching the CWA as thermodynamics weaken. With
decreasing shear as well, will only carry small chances, but the
concern remains for at least an isolated severe wind threat in the
early evening. With the cold front making its way through and mid
level moisture obviously high, will maintain a small PoP area-wide
into the overnight hours.  Overall this continues to be low
confidence precipitation forecast. As for the Heat Advisory, will
continue it at this point. Locations in the northeast in particular
may remain too cool to approach 105F apparent temps, specially if
the mid/high cloud continues to develop, but with several more hours
until sunset and dewpoints remaining along and north of the weak
surface trough over northern Kansas, the potential for a quick jump
in heat indices seems possible.

.LONG TERM...(Sunday Night through Saturday)
Issued at 329 PM CDT SAT JUL 26 2014

Monday and Tuesday continue to look dry as a modified Canadian
surface ridge of high pressure builds south through the plains.
Models show northwest flow aloft with no obvious shortwave moving
over the area. Therefore will continue with a dry forecast since
there is no strong signal of forcing. Models show good mixing and
with some insolation, afternoon highs should reach the mid 80s.
Trended lows a degree or two cooler thinking skies would remain
mostly clear allowing for decent radiational cooling.

Tuesday night through Wednesday night, models continue to show
shortwave energy rounding the upper ridge over the mountains and
moving across the central high plains. This should bring a chance
for precip with POPs increasing as one moves west. The GFS BUFKIT
soundings are showing a little better instability developing mid
week so have simply gone with a chance for showers and
thunderstorms. With expected cloud cover the diurnal change in
temps is expected to be a couple degree less and have Lows a
degree or two warmer with highs a degree or two cooler.

For Thursday through Saturday, confidence in the meso scale
details decreases. The overall pattern has the longwave trough
remaining over the eastern half with the potential for a weak
disturbance to move overhead. Additionally models have little or
no inhibition due to cool mid level temps. So confidence is precip
chances is low because there is nothing to prevent storms from
developing but no clear signal that would force storms to form
either. Continued with small POPS for Thursday and Friday, but
then have a dry forecast for Saturday. Temps should remain below
normal as long as the longwave trough remains over the plains
keeping the hot air over the west.


.AVIATION...(For the 06Z TAFs through 06Z Sunday Night)
Issued at 1140 PM CDT SAT JUL 26 2014

Expect VFR conditions for the next 24 hours. North winds will
increase to 11 to 14 KTS with higher gusts through the mid morning
hours and continue through the afternoon. Winds will become light
after sunset.




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