Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Lubbock Texas
254 am CDT Monday Oct 20 2014
a closed upper air low was propagating ewrd across northwestern old Mexico early
this morning aiding to transport Gulf moisture across the region.
As such dewpoints have increased by 10 degrees /in the 50s/ since
this time yesterday...thus making chances for low clouds and/fog
more of a possibility later this morning. Model soundings exhibit
scouring low clouds by mid-morning...though middle-upper level
cloudiness will ensue. With the location of the upper air low not
changing much throughout the day today /remaining south of Arizona and
nm/...coupled with enduring low level moisture and steepening
lapse rates /mid-level cape values of 500-1000 j/kg by the afternoon/
may lead to another day of scattered showers and
thunderstorms...with perhaps a little more coverage than
yesterday. However like yesterday...can not rule out a brief
isolated strong thunderstorm.
Meanwhile an upper air trough diving east-southeast across the Great Lakes region this
morning will send down a weak cold front to the southern Texas Panhandle
this afternoon...where it is poised to stall before retreating north tonight.
The NAM and a few high-res solutions hint at precipitation developing
near this front...potentially posing a threat for some of this
activity near/move across portions of the far northern South Plains.
Temperatures today will be a few degrees warmer than yesterday /70s and
80s/ due to a quicker dissipation of the low cloud cover as well
as a slight uptick in 850 mb temperatures. Overnight lows will be
slightly warmer than average /upper 40s to the middle 50s/ given a
persistent upslope surface regime drawing in additional low level
focus continues to be on rain event for Wednesday as a broad
latitude upper trough approaching the West Coast this morning will
move across the plains in the Wednesday to Wednesday night period.
00z WRF-NAM similar to the European model (ecmwf) in amplitude and strength of the
system...its timing and extent and magnitude of precipitation
while the GFS continues to be of lower amplitude and much drier.
Will continue to favor the wetter solutions at this time with the only
meaningful adjustment being to speed up onset and ending of precipitation
by about six hours. Temperatures Wednesday will be the trickiest of the
week. With cloud cover and precipitation expected will cool high temperatures
from previous forecast...mainly western and cntl portions of the forecast
Before then...precipitation Tuesday still appears to favor the southwestern zones
as the low over far West Texas begins to phase with the stronger
trough crossing The Rockies. Middle level moisture advection and
isentropic lift point to bulk of precipitation across the Permian Basin
but with a chance of it moving as far north as the western parts of
the forecast area.
Afterwards...models continue to advertise upper level ridging
across the western Continental U.S. For late week. An upper trough is prognosticated to
break the ridge down next weekend but at this time it appears the mulk of
the energy associated with that system will remain well north of
the Southern Plains. Will thus persist with a dry and mild forecast nudging
temperatures up slightly following model trends.
Preliminary point temps/pops...
Friona 73 49 71 51 67 / 20 20 10 30 50
Tulia 76 51 74 51 70 / 20 20 10 10 50
Plainview 75 52 72 53 69 / 30 20 10 10 50
Levelland 75 52 71 53 69 / 40 20 20 20 50
Lubbock 77 54 73 54 69 / 30 20 10 20 50
Denver City 74 53 70 54 69 / 40 30 30 30 50
Brownfield 75 53 71 54 70 / 40 20 20 20 50
Childress 84 55 80 56 74 / 20 10 10 10 30
spur 79 55 76 56 73 / 20 10 10 10 40
Aspermont 84 56 78 55 77 / 20 10 10 10 40