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Area forecast discussion 
National Weather Service Amarillo Texas
1114 PM CDT Tuesday Mar 31 2015

VFR conditions to prevail through the next 24 hours at all terminal.
Light easterly winds will slowly shift to a southerly direction by
tomorrow morning. Winds will increase once again out of the
southwest with gusts approaching 30 knots. These gusty winds will
diminish after 00z Thursday. A surface trough will move through kguy
towards the end of this taf issuance to shift winds out of the north.
There is a chance for convection tomorrow afternoon but confidence on
occurrence at the terminals is too low to mention in prevailing.


Previous discussion... /issued 925 PM CDT Tuesday Mar 31 2015/

have updated graphical forecasts...cancelling Severe Thunderstorm
Watch early in eastern Texas Panhandle and lowering evening
thunderstorm coverage to isolated in eastern sections. Coverage and
intensity of thunderstorms has diminished notably with loss of
insolation. Updated text products being issued at this time.


Previous discussion... /issued 636 PM CDT Tuesday Mar 31 2015/


An outflow boundary from convection to the east may reach kama
by around 01z causing winds to become southeasterly and increase to
around 12 knots or less. At kguy and kdht winds will be easterly or
southeasterly as well at generally 10 knots or less tonight. Winds
will gradually veer around and become southwesterly by morning and
increase tomorrow afternoon with gusts over 20 knots possible after
about 17z. VFR conditions will prevail. Showers and thunderstorms will
be east of all three terminals this evening and again tomorrow


Previous discussion... /issued 441 PM CDT Tuesday Mar 31 2015/

primary forecast concerns include thunderstorm potential through this
evening and again Wednesday afternoon and evening...along with
elevated to critical fire weather conditions Wednesday and Thursday.

Convection is trying to get going late this afternoon across portions
of the southern and eastern Texas Panhandle. Decent instability is in
place across the eastern Texas Panhandle where strong diurnal
heating...steep middle-level lapse rates...and surface dewpoints around
50f have yielded 0-1 km MLCAPES of 1000-2000 j/kg. This instability
combined with 30 kts of effective bulk shear will support storm
organization...and the potential for some severe hail and winds late
this afternoon and evening. The main question is the degree of
forcing...which remains rather weak. Diurnal heating has eroded much
of the cap this afternoon...although mesoanalysis data shows some
weak cin remaining in the eastern panhandles where the better
moisture/instability exists. Weak surface convergence and/or weak
southeast low-level flow associated with a surface low south of the
area may be enough to aid convective development however. Farther
west...dewpoints have mixed into the 20s and 30s...limiting any
convective potential. Could however see a virga shower drift into the
far northwest panhandles off the Raton Mesa this evening. Expect any
storms to dissipate by middle to late evening as daytime heating is

On upper trough will move east across the northern
rockies and plains...with a trailing trough along the West Coast. A
resultant increase in middle/upper flow will promote Lee cyclogenesis
over the Central High plains with surface troughing extending south
through the panhandles. The dryline will mix eastward through the
eastern panhandles during the afternoon...aided by dry downslope
southwest winds. Still uncertainty as to whether the dryline will mix
all the way into western OK before any storms initiate or hang up in
the eastern panhandles. Given this uncertainty...have inserted some
slight chance probability of precipitation in the eastern zones Wednesday afternoon and
evening. Very strong heating will likely erode much if not all of
the cap...but forcing again appears weak and not well-focused. The
dryline looks fairly diffuse...although some weak low-level
convergence is prognosticated...but the stronger upper dynamics will remain
to our north. If storms are able to form in the eastern
panhandles...expected instability and shear support some strong to
marginally severe convection. West of the weather
concerns will be the story /details below/. High temperatures will
likely approach records as they soar into the upper 80s to lower 90s.

A cold front will move through Wednesday night...ushering in slightly
cooler conditions for Thursday. A much stronger cold front will come
through Thursday night...with highs only expected to reach the 50s
and lower 60s on Friday as a 1025 mb surface high builds in behind
the front. Could see a few rain showers across the OK Panhandle
Thursday night as dynamics with an upper trough scrape the area. Lows
expected to fall into the 30s in most locations Friday night...with a
frost or freeze possible for at least parts of the area.

Temperatures will rebound over the weekend into early next week as
quasi-zonal upper flow/low-amplitude ridging eventually gives way to
southwest flow downstream of a western upper trough. It looks like
any thunderstorm chances during this time will remain east of the


Fire weather...
elevated to critical fire weather conditions are expected across
western and central portions of the panhandles on Wednesday.
Temperatures will warm some 20 degrees above average /and near record
values/ with a pronounced thermal ridge in place...leading to relative
humidities of 8 to 15 percent west of the dryline. Southwest winds of
15 to 25 miles per hour with higher gusts may be somewhat marginal across parts
of the area for critical fire weather conditions due to a surface
trough across the area...but this will be offset some by the very
warm and dry conditions...thus a Fire Weather Watch has been issued.
Elevated to critical fire weather conditions will likely develop
across western portions of the Texas Panhandle again on Thursday. A
stronger cold front will move through Thursday night...bringing a
wind shift to the north but alleviating fire weather conditions for
Friday. However...a return to warm...dry...breezy conditions is
expected over the weekend into early next week...bringing a return of
fire weather concerns.



Ama watches/warnings/advisories...
Texas...Fire Weather Watch from Wednesday afternoon through Wednesday
evening for the following zones: Armstrong...Carson...
Dallam...Deaf Smith...Hansford...Hartley...Hutchinson...

OK...Fire Weather Watch from Wednesday afternoon through Wednesday
evening for the following zones: Cimarron...Texas.




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