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Area forecast discussion...updated 
National Weather Service Amarillo Texas
1150 am CDT Wednesday Apr 16 2014

winds will be gusty from the north and northeast behind a cold front
for much of this forecast. Rain chances will increase after midnight
at the Guy taf site as an upper level disturbance approaches. Have
gone ahead and added a prevailing group with -shra and ceilings in the
MVFR range. MVFR ceilings will move into the dht and Ama taf sites as
well during the early morning hours on Thursday. Some light rain
will be possible at the dht taf site...but visibilities are not
expected to fall below 6 have not mentioned this
possibility at this time.


Previous discussion... /issued 711 am CDT Wednesday Apr 16 2014/

for the 12z tafs...a cold front will move across the terminal sites
today...followed by passage of an upper level low pressure system
later tonight into Thursday morning. Surface winds will increase behind
the cold front. Clouds and ceilings will gradually lower during this forecast
period. Highest confidence and greatest threat for showers will be at
kguy and have included a mention for last 6 hours of this forecast. Showers
may also occur at kdht late tonight but confidence is lower so did
not mention at this time. Kama will have a slight chance for showers
and have omitted this element at that taf site.


Previous discussion... /issued 456 am CDT Wednesday Apr 16 2014/

Short term...
early morning WV satellite imagery depicts a shortwave trough over
the northern rockies. This disturbance will dig further to the
southeast today while a surface low moves across the Central Plains.
A secondary surface low over West Texas will strengthen and slide
southeast in response to an upper level disturbance moving along the
southern periphery of the upper trough. A cold front will move across
the area this afternoon...although it may stall across the central
Texas Panhandle initially. This can complicate the forecast today
although thankfully the air mass behind the front is not too much
colder making for a less tricky temperature forecast. In fact highs today
will range from the middle 60s to the middle 70s. Return flow sets up
across the area behind the front...allowing for an increase in
atmospheric moisture. Fairly dry air mass is currently across the
area so it will take some time for the atmosphere to sufficiently
moisten up to support rain chances this evening. The upper trough
deepens as it moves over the area tonight...focusing the maximum area of
lift across the OK Panhandle and the northern Texas Panhandle. This will
be the most likely area to receive rainfall during this period...but
did maintain at least a slight chance pop across the southern Texas
Panhandle. The upper trough will push east of the area by Thursday
evening. Skies will clear although light south-southeast winds will
maintain adequate moisture over the area. So despite temperatures cooling
back into the 50s Thursday...overnight lows are expected to stay
above freezing.

Long term...
still looks like Easter weekend will feature periods of showers and
thunderstorms...although the bulk of this activity will occur
Saturday as an upper trough emerges out of Southern California. Ahead of this
system...shortwave ridging will push temperatures back into the 70s Friday.
This upper trough will lift across The Four Corners region Saturday.
Moisture levels remain high enough to support scattered showers and
thunderstorms especially as synoptic scale lift increases across the
area. Instability doesn/T look too impressive to support organized
severe weather. Medium range models have backed off on precipitation chances
going into Easter Sunday due to a further northern track of this trough
but a few storms may continue over the eastern zones in the morning
so left in the inherited slight chance probability of precipitation for this period. The
GFS has backed off on precipitation chances early next week and is more in
line with the drier European model (ecmwf). An upper ridge will be aligned across the
Southern Plains at this time so without any synopic scale support...expect
dry weather with near normal temperatures. The potential exists for another round
of showers and thunderstorms middle week as an upper low/trough dives
out of the Pacific northwest. The GFS is showing this as a closed low
versus a weaker open trough as advertised by the European model (ecmwf). Still plenty
of time to assess future model runs before biting off on adding
precipitation chances as model output will likely change before then.


Fire weather...
elevated fire weather conditions are expected over the southern
Texas Panhandle...ahead of a cold front. South winds of 15 to 20 miles per hour
will develop this morning across this area and persist into the
afternoon. Winds will turn to the east and northeast and are expected
to weaken later in the day. Relative humidity values will range
around 10 percent in this area...and will rise to above 20 percent
by this evening. Rain chances will increase tonight and Thursday across
the area. Neither elevated or critical fire weather conditions are
expected after today as higher moisture levels will result in
minimum relative humidity values above 20 percent.



Ama watches/warnings/advisories...