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Area forecast discussion 
National Weather Service Lubbock Texas
1233 PM CDT Sat Jul 4 2015

Aviation...
VFR conditions expected this taf cycle. Scattered deck at all terminals
will lift through the afternoon with any convection well NE of kcds.
Moisture continues to hang around overnight but latest guidance
keeps MVFR ceilings south and east of klbb with veering winds so have
followed suit.

&&

Previous discussion... /issued 410 am CDT Sat Jul 4 2015/

Short term...
the synoptic pattern early this morning was comprised of upper air
troughiness across the Great Lakes region and upper air ridging across the
southern rockies...with the center of the upper Air Ridge noted west of The Four-
Corners region. As a result...northwest flow aloft prevailed across the
Southern Plains. Embedded impulses within the said flow aloft
coupled with an old cold frontal boundary/outflow boundary across
the panhandles has resulted in a cluster of storms which initiated
across the OK Panhandle yesterday evening...but has since translated
to across the northwest South Plains. The convection was gradually sagging
swwrd with localized moderate rain being the primary threat...as
indicative by ttu mesonet sites reported one-hourly rain rates from
a few hundredths of an inch up to near one inch underneath the
heaviest cores earlier this morning. However...the frequency of
lightning dropping off quite a bit and a downward trend in strength
via radar analysis have since caused the rainfall rates to decline.
High-res models such as the hrrr and ttu WRF appear to have a decent
handle on this convection...as it is expected to continue to wane
whilst propagating to across eastern nm by at or above 10z.

For the remainder of the 4th of July...the upper Air Ridge is prognosticated to
shift ewrd to across central/eastern nm by late afternoon/early
evening...thus promoting subsidence to have more influence across
the region. The result will be storms being maintained more so
across central nm nearest to a surface trough. Although...there are hints
of a lingering old frontal boundary/outflow boundary across the western
panhandles/western OK coupled with a decent 250 mb jet streak /50 kts or
so/ within the northwest flow aloft and surface-based cape values of 1.0-1.5
kj/kg across the northern rolling plains...may result in a few storms
/possibly nearing strong levels/ that could try to develop near the
aforementioned areas this afternoon and evening. As such...will hold on
to slight chance probability of precipitation across the northern rolling plains. Srly surface winds
will become slightly breezy this afternoon /15 kts or so/ courtesy of the
nearby surface trough promoting a bit of a tightened pressure gradient.
All in all...the 4th of July will be comprised of low /albeit non-
zero/ rain chances...slightly breezy conditions in the afternoon with
seasonal warmth expected /upper 80s to lower 90s/. Tonight...a
notable decline in wind speeds will occur...and mild conditions will
ensue with overnight lows ranging from the middle 60s across the SW
Texas Panhandle to lower 70s across the rolling plains. This will make
for a pleasant night to observe fireworks.

Long term...
upper ridge axis passing overhead Sunday followed by moistening
southwest flow Sunday night and Monday in advance of a full
latitude trough gradually passing Monday night and Tuesday.
Precipitation signals have mostly disappeared Sunday...while
remaining a bit mixed Sunday night as monsoonal moisture starts
to spread in. By Monday deeper moisture will be moving in from the
west while a fairly sharp upper trough digs into the Southern
Plains along with a frontal boundary. Unsure if we will see
significant precipitation prior to approach of the cold front late
Monday night which by then aligns with solid precipitation signals
from all solutions though different focus areas. More solution
differences factor in early Tuesday as WRF/NAM remains sharpest
if not even closed off at h500 mb and thus also wettest. But high
chance to likely categories for precipitation appear valid. Upper
trough will steer off to the east late Tuesday and Wednesday
allowing building heights aloft though we may see another ripple
or two with enough energy for at least a low chance for thunder
even into early Thursday before ridge builds further. Better
agreement by the end of the week and next weekend on a Southern
Plains upper ridge which should suppress storms except near the
monsoon flow which will re-establish to our west. Previous
forecast still mostly valid therefore. Temperatures will trend
cooler middle week and warmer afterwards. Rmcqueen

&&

Preliminary point temps/pops...
Friona 65 91 67 87 / 10 10 20 50
Tulia 67 91 70 87 / 10 10 20 40
Plainview 67 90 70 87 / 10 10 20 40
Levelland 67 92 71 91 / 10 10 20 40
Lubbock 68 92 71 90 / 10 10 20 40
Denver City 66 92 70 92 / 10 10 20 30
Brownfield 68 92 70 91 / 10 10 20 30
Childress 72 95 74 93 / 10 0 20 30
spur 70 91 71 92 / 10 10 10 30
Aspermont 73 94 74 94 / 10 10 10 30

&&

Lub watches/warnings/advisories...
none.
&&

$$

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