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Area forecast discussion...updated 
National Weather Service Amarillo Texas
641 am CDT Tuesday Jul 28 2015

for the 12z tafs...isolated to scattered thunderstorms are expected to develop across
the area later this afternoon through tonight as a cold front affects
the southern High Plains. Greatest likelihood of thunderstorms appears to be at
kguy and kdht...and have included thunderstorms in the vicinity at both those sites. Thunderstorm
potential at kama is a bit more problematic with lower confidence in
that taf site being affected. Therefore...have omitted thunderstorms from the
kama taf for this forecast cycle.



Previous discussion... /issued 422 am CDT Tuesday Jul 28 2015/

Short term...tonight through Friday morning...
upper level trough making progress across Montana this morning...and
the upper level ridge over the panhandles continues to flatten and
axis shifts eastward. A weak cold front has made it through most of
Colorado...and will continue sagging southward through the morning.
Precipitation chances still look decent beginning this afternoon and
evening as scattered showers and thunderstorms develop along the
surface convergence of the front. Moist...southeasterly flow will
advect in surface based moisture...and moisture plume that has setup
shop further west will move eastward into the panhandles as the
ridge is suppressed. Have slowed progress of the front by just a few
hours from previous package...resulting in a delay to middle-late
afternoon to begin precipitation chances. Highest chances for precipitation
remain over the Oklahoma Panhandle and most of the Texas
Panhandle...though some discrepancies remain as to how far the south
progresses this afternoon and evening. Upper level trough currently
assisting somewhat in the front's progress will lift northward into
Canada. convection develops this evening and
overnight...resultant cold pool may be enough to progress the front
further south across the eastern Texas Panhandle as well. Primary
hazard will again be localized flooding from heavy rain. Precipitable water values
are not as high as previous systems of late...ranging from 1.25 to
1.75 inches...but remain elevated enough to expect widespread totals
of half inch or greater across the panhandles...with locally higher
amounts expected during convective events. A few strong storms are
possible...with damaging winds the most probable threat from
individual storms...though shear values remain weak over all but the
far northern areas.
Chances for rain continue through the next few days as the panhandles
remain on the periphery of the ridge and subtle disturbances move
through. Upper level flow remains west to southwesterly through
Wednesday...and southeasterly surface flow could possibly remain across the
far southeastern zones into Wednesday and support continued rain
chances. While the previously mentioned cold front does not have an
appreciable temperature difference accompanying it...lingering cloud
cover over the next few days will keep maximum temperatures lower so
have continued trend for lower than normal temperatures on Wednesday and
rebounding slightly closer to normal on Thursday. Upper level flow
turns more northwesterly on Thursday...renewing chances for probability of precipitation
across the northern half of the County Warning Area and for localized flooding. The
Oklahoma Panhandle and northern Texas Panhandle remain the most
likely locations to receive higher amounts through the short term.


Long term...Friday through Wednesday...
northwesterly flow returns as the ridge moves back westward. This
will allow for several disturbances of upper level vorticity to move
through the area and create chances for rain every day in the
extended. Afternoon highs will be kept from reaching into the upper
90s due to the extra cloud cover.



Ama watches/warnings/advisories...



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