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Area forecast discussion 
National Weather Service Amarillo Texas
1130 am CST Friday Nov 27 2015

18z tafs...brief lull in frozen precipitation this afternoon. Medium
confidence on the timing of its return...21z at the earliest with
heavier rates after 00z. Freezing rain with some sleet is most
likely at kama...while further north across the panhandles think it
will be more of a snow/sleet mix. MVFR or IFR conditions are expected
most of today...with LIFR likely late tonight/early Saturday
morning. Freezing drizzle or freezing fog is possible after the
heavier precipitation ends tomorrow morning.



Previous discussion... /issued 603 am CST Friday Nov 27 2015/

updated for 12z aviation discussion below. Also...a note on the 12z
Amarillo sounding. A warm nose reaching about 6.5 degree celsius at 750
mb...with 0 degree or warmer between 3000 feet to 9500 feet. Drier air
mixing in above 600 mb. This warm layer and the drier air above it
supports the observed light freezing drizzle and very light sleet and
snow across southern portions of the Texas Panhandle. Cooler temperatures
aloft farther north have allowed for some light snow in those areas
this am.


for the 12z tafs...IFR conditions expected to prevail through most of
the period...with temporarily better ceilings or visibilities during
periods of precipitation. North winds gusting up to 25 to 30 kts
through the afternoon. Then after 00z...wind speeds will
decrease...and ceilings and visibilities could drop into LIFR
ranges. Kguy...could see some improving conditions near the very end
of the period. Periods of light to moderate freezing
rain...sleet...and snow will affect all taf sites through the period.


Previous discussion... /issued 307 am CST Friday Nov 27 2015/

long fetch of subtropical moisture will continue to override our
Canadian air mass at the surface ahead of a large positively tilted
upper level trough which is located over Nevada and Southern
California. This moisture will continue to provide the panhandles
with a wintry mix of precipitation today through Saturday. Latest
forecast soundings suggest that the warm nose will erode some over
the Winter Storm Warning area would expect to see a
little more sleet and snow. The warm nose over the Ice Storm Warning
area will only slowly erode. So freezing rain and sleet are expected
to be the main precipitation types. However...some snow has already
been reported especially in the central Texas Panhandle. Believe
that the snow will continue to mix in with the freezing rain and
sleet from time to time today given the moisture in the dendritic
growth zone. So any convective shower that moves over will certainly
be able to produce some frozen precipitation at the ground. Still
think...the freezing rain will be the main story through the end of
the Ice Storm Warning as the dendritic growth zone loses its
moisture tonight into Saturday. Our precipitation type may switch over to
more of a freezing drizzle then.

Have gone ahead and started to decrease some probability of precipitation Saturday into
Saturday night as it now looks like the best moisture will be moving
to the east of our area quicker.

We may still have another brief bout of mixed precipitation...mainly
across the northern County Warning Area Sunday night as the main upper level trough
lifts northeast into the plains.

The rest of the forecast will remain dry with a slow warming trend.


Ama watches/warnings/advisories...
Texas...Ice Storm Warning until noon CST Saturday for the following
zones: Armstrong...Carson...Collingsworth...Deaf Smith...

Winter Storm Warning until noon CST Saturday for the following
zones: Dallam...Hartley...Sherman.

OK...Ice Storm Warning until noon CST Saturday for the following
zones: Beaver.

Winter Storm Warning until noon CST Saturday for the following
zones: Cimarron...Texas.




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