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Area forecast discussion...updated 
National Weather Service Amarillo Texas
1217 PM CDT Monday Jul 6 2015

for 18z tafs...a cold front has pushed through most of the Texas
Panhandle. As a result...north to northeast winds will be on the
increase for the rest of afternoon and evening. Winds will be around
15 to 20 kts with gusts near 25 to 30 kts. Plenty of moisture will
exist around the frontal boundary and a disturbance moving out of New
Mexico will also be in play. Therefore...the mention of
thunderstorms will be included at all taf sites through the night.
Lower confidence at kdht and kguy as these sites will be well north
of the front...but activity associated with the disturbance and
continued moisture will be a factor. By early Tuesday
morning...northeasterly winds will continue to advect moisture into
the region and ceilings could fall to MVFR and even IFR levels
especially after 09z. MVFR visibilities also expected with light rain
and mist.



Previous discussion... /issued 636 am CDT Monday Jul 6 2015/

wind shift associated with incoming cold front has passed through
northwest corner of forecast area...with shift to northerly surface
wind expected by 13z today at kguy. Atmosphere is very moist...with
further increase in low- and middle-level moisture expected today and
tonight. Shortwave trough will induce vorticity maxima which will
provide large-scale ascent to promote thunderstorm development today
and tonight...particularly along and near cold front which is
expected to pass through kama around 22z today. North northeast
surface winds expected to gust into the 25 to 30 knots range following
frontal passage...with potential for thunderstorms continuing this
evening and tonight. MVFR or lower ceilings expected to develop this
evening and overnight as cool and moist surface ridge builds
southward into the area.


Previous discussion... /issued 451 am CDT Monday Jul 6 2015/

breezy southerly winds continue to advect higher dewpoints across the
area this morning...with most locations in the middle 60s. A fairly
strong cold front for this time of year continues its southerly track
towards the panhandles. Still even at this short range...some
distinct differences in the southward progress of the cold front
remains between the the short term portions of the
forecast a fair amount of uncertainty. Appears the front will move
freely through the western portions of the panhandles during the day
today...but the models diverge quite a bit in the southward progress
over the eastern Texas Panhandle. The frontal position and associated
convergence will play a major role in how the precipitation pattern
sets up this afternoon and evening. Regardless of the final
location...precipitable water values of 1.75-2+ inches are expected over the
eastern panhandles Monday night and into Tuesday so feel pretty
confident in including those far southeastern counties in the Flash
Flood Watch this afternoon through Tuesday. Questions start arising
for the westward extent of the watch and the temporal extent...and
will pass these concerns along for the next shift to consider as
frontal progress becomes more apparent. Heavy rainfall definitely
appears to the main hazard with this system. The potential for some
strong to severe storms will also depend greatly on the front. Shear
values are not particularly impressive...30 to 40kts at most but
are positioned further north across the Oklahoma and northern Texas
Panhandle. This area is expected to be behind the main forcing at the
surface and in an area of less available instability. Areas further
south should be able to realize some fairly decent instability later
this afternoon with ample moisture and warm temperatures expected
before the front passes. Some upper level support arrives tonight and
remains through Wednesday in the form of the ridge retreating
southward and flow turning more westerly...which will also help keep
the possibility for showers and thunderstorms to persist through the
overnight hours.

Beyond this frontal system...the panhandles remain in westerly flow
through Thursday when an upper level ridge starts to build northward
across Mexico and Texas. Have kept slight chance to chance probability of precipitation
during this time and attempted to narrow down the most likely
locations and times...but with weak westerly flow...shortwave
activity will likely drive those factors and will be better resolved
as the week progresses. The ridge looks to continue building and
should keep the area mostly dry Friday and through the weekend.



Ama watches/warnings/advisories...
Texas...Flash Flood Watch through Tuesday afternoon for the following
zones: Armstrong...Carson...Collingsworth...Donley...gray...




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