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Area forecast discussion 
National Weather Service Lubbock Texas
258 am CDT sun Oct 4 2015

Short term...
the upper Air Ridge has exited the response to a deepening upper air
low translating south-southeast across northern cali. This upper air low will not only
promote the sharpening of the SW flow aloft /which is aiding in
streaming Pacific middle-upper level moisture across the Southern
Plains this morning...but will also maintain nearby surface Lee
troughing and lowered 500 mb height fields. Looking at the surface...a
persistent upslope surface regime is keeping precipitable waters at or above 1.00 inch across
the County Warning Area...whilst a 15-25 knots low level jet Cranks away this morning thus
resulting in adequate isentropic upglide. It is therefore not
surprising to see an ongoing batch of scattered showers and
thunderstorms stretched from eastern nm to across the west South
Plains...and NE to across the southern Texas Panhandle...leaving portions of
the central and eastern zones dry per 07z radar analysis. The ttu
mesonet reported a few cities receiving rainfall amounts of a few
tenths of an inch so far this morning...but since this swath of
rainfall has been in place across the western zones since last
night...totals of a half-inch up to around 1.00 inch or so is more
representative. Motorist are therefore urged to approach low-lying and
poor drainage areas with caution.

The hrrr and ttu WRF appears to have a good handle on the current
precipitation situation...and as such shows the activity gradually shifting
ewrd to across the central zones in the next few hours and
endure...with a notable lull occurring by mid-morning. This lull may
not last very long as the NAM and GFS solutions hint at an 80+ knots
250 mb jet maximum nearing the County Warning Area from the southwest this afternoon and
hence...provide that large scale ascent to re-generate storms more
so for locales on The Caprock /especially near the Texas/nm border/.
This jet maximum will be exiting/waning by tonight though lingering
storms are shown to occur near the Texas/nm border. It is interesting
to note that this precipitation activity is shown to have a hard time
spreading ewrd to portions of the rolling plains. Solutions are
likely picking up on a tongue of drier air filtering in across the
said area throughout the short term period /lower 40 dewpoints
versus upper 40s and lower 50s/. This can be seen not only via the
metars and their 07z reported dewpoints but also prognosticated model
soundings exhibiting moist middle-high levels but drier low levels.
Will therefore show highest probability of precipitation across the western zones with none probability of precipitation
across the far eastern zones. Guidance temperatures running a bit too warm as
was the case yesterday where many locations struggled to surpass the
60s. Will therefore go below guidance and show highs in the 60s for
all but the Low Rolling Plains /70s/...with overnight lows in the
40s and 50s.

Long term...
precipitation should come to an end by midday Monday as heights rise over
the Southern Plains as a result of modest amplification of the upper
flow over the Continental U.S. In response to approach of the closed low over
southern calif. Brief period of no precipitation to last until late Tuesday
night when height falls begin as the upper low moves toward western
New Mexico. Best lift across the forecast area to occur Wednesday and
Thursday as the low moves from eastern Arizona to The Big Bend. Likely
probability of precipitation through that period remain on track. Beyond Thursday models
diverge with the GFS shearing the upper low over west central
Texas but not until a mature deformation sets up over the forecast
area. This is followed by the trough splitting with some energy
ejecting quickly eastward and some moving SW then west and closing off
again underneath a developing ridge over The Rockies. This latter
part is similar to the European model (ecmwf) which maintains the upper low...
moving it from The Big Bend westward across northern Mexico. GFS has been
playing catch-up the last several days...and will continue to
favor the European model (ecmwf). That would see precipitation chances begin to diminish
from north to south...if not by least by Friday night.
Temperatures through the period should run below normal with the cloud
cover and precipitation predominant. Exception would be the middle day
between Tuesday...which should be close to seasonal


Preliminary point temps/pops...
Friona 60 47 65 50 / 70 20 20 10
Tulia 61 48 66 50 / 50 20 20 10
Plainview 61 49 66 51 / 40 20 20 10
Levelland 65 51 64 52 / 50 30 30 10
Lubbock 67 52 65 52 / 40 30 30 10
Denver City 68 52 66 54 / 60 40 30 10
Brownfield 69 53 66 53 / 50 30 30 10
Childress 69 54 71 56 / 10 10 20 0
spur 71 54 68 54 / 10 10 20 10
Aspermont 77 57 73 55 / 10 0 10 0


Lub watches/warnings/advisories...



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