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Area forecast discussion...updated 
National Weather Service Amarillo Texas
1146 am CDT Wednesday Oct 7 2015

the best chance for more steady rain looks to be at dht and Guy. Ama
will probably see more breaks in the clouds which could lead to a
better chance of thunderstorms and rain later this afternoon. So have inserted a tempo
group for thunderstorms and rain there. MVFR conditions are expected with the rain
through late this afternoon. The rain is expected to stay to the
west of the taf sites overnight. Winds should remain below 10 knots
for the most part and they will tend to pick a southerly or
southwesterly direction. Skies will remain VFR outside of the rain showers
and thunderstorms and rain.


Previous discussion... /issued 650 am CDT Wednesday Oct 7 2015/

expanded higher probability of precipitation eastward this morning based on current radar
trends. No other significant changes made at this time.


12z tafs...showers and embedded thunderstorms will continue to
develop and move northeast across the panhandles today ahead of an
upper-level low pressure system over Arizona. Overall...VFR conditions
will prevail even in the lighter showers...however periods of MVFR
visibilities/ceilings will be possible in the heavier showers and storms.
Greater precipitation chances for the terminals will be through this
afternoon...with the more widespread showers and storms then expected
to shift southward this evening and overnight. Winds will remain
light through the period...generally at or below 12 kts.


Previous discussion... /issued 437 am CDT Wednesday Oct 7 2015/

upper level low spinning over Arizona this morning and slowing down
its eastward progression. Subtropical moisture plume spreading
across New Mexico and West Texas. Shortwave energy rounding the base
of the trough and low level jet helping to increase coverage of
showers and thunderstorms over the western panhandles for this early
morning round of convection. As the day progresses...upper level low
will continue digging southward into Mexico and heights will fall
over the panhandles...with bulk shear values remaining around 20 to 30kts
across the panhandles. At the area of convergence is
expected to remain near the nm/Texas border. Models hinting that this
area may be able to clear out some this afternoon...and realize a
relatively small area of surface based instability to aid in the
development of some strong to marginally severe thunderstorms. Precipitable water
values of an inch to around 1.25 inches will allow for some locally
heavy rainfall as well from any convection that develops. As the
evening progresses...the upper level low will drift further into
Mexico and heights will rise across the Oklahoma and northern Texas
Panhandle. The better dynamics for stronger storms will move
south...though scattered showers with some embedded thunderstorms and
locally heavy rainfall will remain possible across the southwestern
Texas Panhandle through much of the day Thursday.

As the upper level low departs further south...a broad upper level
trough across Canada will help force a cold front through the
panhandles early Friday morning. While scattered showers and
some embedded thunderstorms will be possible with this system...drier
air is expected to filter in pretty quickly behind it along with
rapidly rising heights as the upper level low retrogrades back in to
the Pacific. Therefore...have highest chance probability of precipitation for the far
eastern and southern zones on Friday morning and early afternoon
before quickly coming to an end. Also bumped up winds somewhat during
this period behind the front from guidance. Beyond Friday...a dry
forecast looks to prevail as mainly zonal flow in the upper levels
couples with a Lee trough. Have bumped up temperatures a few degrees
above the blend during this time as 850mb temperatures approach the low to
middle 20 degrees c and downsloping flow develops at the
surface...especially on Sunday. Another front will move into the
panhandles on Monday...but guidance is keeping this one a dry passage
at this time.



Ama watches/warnings/advisories...




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