Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion...updated 
National Weather Service Amarillo Texas
1109 PM CDT sun Sep 21 2014

low clouds will continue to increase across the Ama taf site and they
should form over the dht taf site before sunrise. Ceilings should be in
the MVFR range. Guy should be low cloud free. Low clouds will break
up by late morning. Southerly winds will increase at all taf sites by
late morning. Some showers or thunderstorms may try to move into the
dht and Guy taf sites late Monday morning or Monday afternoon...but
will not mention now as chances seem a little slim. The southerly
winds will decrease with sunset Monday evening.


Previous discussion... /issued 613 PM CDT sun Sep 21 2014/

the best chance of a thunderstorm this evening will be at the Ama taf
site. So will continue with a tempo group there. Low clouds should
develop across the Ama and dht taf sites late tonight. For now have
inserted an MVFR ceiling. Will leave low clouds out of Guy for now. Low
clouds should break up by the late morning. Winds will pick up out
of the south by late morning.

Previous discussion... /issued 435 PM CDT sun Sep 21 2014/

slight chance to chance probability of precipitation through most of the next week for
portions of Texas/OK panhandles as shortwave troughs ride around an
upper ridge. With cloud cover and decent moisture around the
panhandles...temperatures will remain near to just below normal most
days. See below for more details.


Short term...tonight through Wednesday...

Through tonight: showers and storms that develop this afternoon will
move to the south and west of the forecast area by 10 PM as the cold
front pushes through. There will be a very small chance that a few
isolated showers/maybe a storm could pop up across the far western
panhandles overnight as moisture transport increases in response to
weak isentropic ascent, but most areas should be dry. Overnight lows
will drop into the 50s areawide. Low clouds will likely form across
the western half of the Panhandle late tonight, but dew point
depressions won't get low enough for fog formation, even across the
far southwest Texas Panhandle where surface moisture will be the
most favorable.

Monday-Monday night: low clouds may be a little stubborn to break up
tomorrow morning on The Caprock, so high temperatures will likely
only make it into the lower to middle 70s. As an upper trough ejects
into the central rockies, strengthening Cross Mountain flow will
promote the development of a Lee side surface low. In response to
this, surface winds will shift to the south and increase into the 10
to 20 miles per hour range. A few showers and storms could develop ahead of the
surface trough in northeast New Mexico tomorrow afternoon and sneak
into the western panhandles. Most of this activity will remain
confined to locations west of a Guymon to Hereford line through the
early evenings hours. Owing to minimal solar radiation in these
areas tomorrow, instability will not be favorable for any severe
storms. Some showers/storms could linger into the overnight hours as
they will be aided by a weak shortwave trough.

Tuesday-Tuesday night: the surface trough will set up a little
farther east Tuesday afternoon, but negligible forcing for ascent
should keep most of the area dry through the daylight hours. With
breezier southerly flow and less clouds, highs will warm into the
upper 70s to middle 80s. There might be a slightly better opportunity
for showers and storms Tuesday night across the northeast panhandles
as a lobe of vorticity breaks off from the main upper trough across
the Central Plains and moves southeast. However, the best chances
for rain should remain to our north and east across Kansas and

Wednesday-Wednesday night: an amplifying upper ridge over the
eastern U.S. Will lift the polar jet northward and potentially cut
off the upper trough over the Central Plains. Some model solutions
actually suggest this trough retrograding southwest. Even if this
doesn't happen, all guidance suggests enough upper-level energy and
low-level moisture to warrant a chance for rain/storms over more
real estate of the panhandles. Some of the storms could be strong to
severe on Wednesday afternoon and evening as deep layer shear
increases up to 30 knots and mixed layer cape values increase up to
1500 j/kg. Any showers and storms that develop will begin
weakening/dissipating late Wednesday evening.


Long term...Thursday through Sunday...
the forecast becomes a little less certain in the extended
period...but guidance in fairly decent agreement for possible
retrograding shortwave to bring late week thunderstorm chances. At
the tail end of the forecast...a deeper upper-level shortwave trough
digs into the western Continental U.S. Over next weekend and may cut off before
lifting northeastward early next week. Depending on the depth/speed
of this shortwave...could see another shot at showers and
thunderstorms ahead of this shortwave over the weekend.


Fire weather...


Ama watches/warnings/advisories...




National Weather Service Glossary of Abbreviations