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Area forecast discussion 
National Weather Service Lubbock Texas
335 am CDT Thursday Apr 2 2015

Short term...
a weak cold front continues to push south across the Texas Panhandle
early this morning and will drift south into the northeastern half
of the forecast area by sunrise. Wind will remain light out of the
north to northwest through at least middle day before the Lee surface
trough rapidly deepens through the afternoon across eastern New
Mexico. This will bring a return of a gusty southwesterly wind by
this afternoon for all of The Caprock with sustained speeds of 15 to
25 miles per hour and gusts to 30 to 35 miles per hour. Strong downslope component to the
wind along with deep mixing will also help to drop dewpoints into
the teens and boost temperatures into the upper 80s for The Caprock
and lower 90s for the rolling plains. This will also result in
critical fire weather conditions for the South Plains...see the fire
weather section below for more information.

Once the boundary layer decouples shortly after sunset...expect to
see wind speeds drop off but remain out of the west through most of
the night. A stronger cold front will approach the Texas Panhandle
by midnight Friday morning and make rapid progress south through the
overnight hours. There are differences in the timing of the front
but all models have the leading edge of the frontal zone across the
northern rolling plains and northern South Plains by sunrise Friday.
The GFS and European model (ecmwf) are the fastest of the models for a change and
have the front through the entire forecast area by sunrise. Timing
will be critical for low temperatures as cold air advection before
sunrise may help to drop temperatures for the northern two rows of
counties. We opted to go this Route and undercut guidance across
the northern half of the forecast area Friday morning while keeping
the southern half close to guidance.


Long term...
the cold front will quickly exit the County Warning Area to the south to begin
the extended forecast...with gusty northerly winds and much cooler
air in its wake for Friday. Sustained winds of 20 to 30 miles per hour will
be common behind the front much of the day before gradually
decreasing late in the afternoon and more notably by evening. In
addition... it still appears there may be a risk for a brief bout
of Post- frontal stratus across the northern and eastern zones
Friday morning...though signals are mixed on this. Regardless...
temperatures will be about 25 degrees colder than today...with
highs mostly in the lower to middle 60s. A surface ridge will
settle over the region early Saturday bringing much lighter winds
and a cold start to the Holiday weekend...with lows in the 30s to
lower 40s.

Return flow will ensue on Saturday as the surface high shifts across
the southeast states. At the same time...medium range nwp continues
to advertise a couple of weak shortwave troughs embedded in the
developing southwest flow aloft that will race out of the eastern
Pacific and pass somewhere nearby over the weekend. The first wave
is currently projected to graze the area to the south...but it could
be close enough to bring a shot of showers /perhaps an elevated
storm/ to the southeast zones Saturday evening. Initially the low-
levels will be rather dry...but a good slug of middle/upper moisture is
prognosticated to eventually overcome this and bring a shot of
rain...primarily for the rolling plains. Eventually...improved low-
level moisture should advect into the region by early
Sunday...complete with a round of early day stratus. The next quick
moving upper disturbance is then expected to quickly approach around
midday...and with the improving could be enough to Eek
out a few more showers or storms...though it may be east of the
South Plains by peak heating if the current guidance is correct.
Even so...we have accepted the blended guidance which did expand the
slight chance probability of precipitation to include roughly the eastern half of the County Warning Area on

Southwesterly flow aloft is then expected to persist through the
middle of next week as some form of troughing lingers across the
western states. At the surface...a dryline will likely be in place
in the region...though modestly strong westerly flow and strong
heating will likely mean it will advect/mix to our east by peak
heating...keeping the best thunder chances to our east. Instead a
period of elevated to critical fire weather appears to be a more
likely outcome for much of the forecast area as temperatures warm back to 10-
15+ degrees above average. A storm system passing across the
northern tier of the nation may attempt to propel a cold front into
the region Tuesday and Wednesday...though whether or not it makes it
into the County Warning Area or stalls to the north is unclear at this time. For now...the
forecast reflects a slight cooling trend into the middle of next
week...though this is subject to change.


Fire weather...
after a quiet start to the morning...expect to see fire weather
conditions deteriorate through the afternoon. West wind will
increase through the afternoon with 20 foot wind speeds eventually
reaching into the 20 to 30 miles per hour range...minimum afternoon relative humidity values
will fall to at or around 10 percent...and temperatures will be
above normal. Although fuels are not critically dry over most of
the area and spotty rainfall has fallen across the South
Plains...the majority of fuels remain dry. Will issue a red flag
warning for all of the South Plains and counties along the edge of
The Caprock for this afternoon through early evening. Conditions
across the rolling plains should not be quite as bad and will not
have any products for this area as wind speeds will remain at or
under 15 miles per hour.

A cold front will follow early Friday with gusty northerly winds
sustained at 20 to 30 miles per hour much of the day. These winds will carry in
much cooler air...with afternoon highs about 25 degrees colder than
today /mostly in the 60s/. Even with the gusty winds...relatively
higher humidity levels will bring a reprieve from the heightened
fire weather concerns. However...a return of warm...dry and breezy
conditions are expected by early next week.


Preliminary point temps/pops...
Friona 81 39 58 32 / 0 0 0 0
Tulia 84 42 59 34 / 0 0 0 0
Plainview 85 42 61 35 / 0 0 0 0
Levelland 86 45 64 36 / 0 0 0 0
Lubbock 88 45 64 37 / 0 0 0 0
Denver City 86 52 66 39 / 0 0 0 0
Brownfield 87 50 65 38 / 0 0 0 0
Childress 89 46 65 39 / 0 0 0 0
spur 90 51 64 39 / 0 0 0 0
Aspermont 93 58 66 41 / 0 0 0 0


Lub watches/warnings/advisories...
red flag warning from 1 PM this afternoon to 9 PM CDT this
evening for txz021>024-027>030-033>036-039>042.




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