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FXUS64 KLUB 241524 AAA
AFDLUB

Area Forecast Discussion...UPDATED
National Weather Service Lubbock TX
1024 AM CDT Mon Jul 24 2017

.UPDATE...
We`ve removed the PoP mention for the remainder of the morning as
activity in the Southern Rolling Plains has died off and we should
see a lull in the action while temperatures warm and we start our
diurnal destabilization routine.

Despite the dearth of any significant lift aloft, the atmosphere
remains very moist across the forecast area today with precip.
water values in excess of 1.3 inches area-wide. Strong heating
should generate scattered t-storm activity by early afternoon -
much as we`ve seen the past couple of days. The lack of strong
flow aloft and any pronounced boundaries should keep the activity
unorganized and outflow-dominate. No significant changes to the
forecast at this time.

&&

.PREV DISCUSSION... /issued 644 AM CDT Mon Jul 24 2017/

AVIATION...
VFR conditions in place will continue through the day. There
remains a good chance of scattered thunderstorms this afternoon at
all three TAF sites and have continued PROB30 groups. Still a bit
hard to pinpoint the most favored time but the PROB30 seems to
line up well with the best coverage in the computer forecasts.

Jordan

PREV DISCUSSION... /issued 359 AM CDT Mon Jul 24 2017/

DISCUSSION...
Subtropical upper high poised over the scenic inselberg of Shiprock,
NM will set its sights on the flatter Texas South Plains later today
and overnight. Until this high arrives on Tue, respectable mid-level
lapse rates will remain intact and support one last bout of isolated
to scattered storms, mostly in the afternoon and early evening. Foci
for precip today are more vague than yesterday`s pair of MCVs, but
fine resolution water vapor imagery does show a very subtle cyclonic
curl near Hereford drifting southward. This could focus PoPs more
over the western South Plains today, but have opted to keep a broad
scattered mention as no clear signal exists at this point to justify
further tweaking to PoPs. A large, but weak outflow boundary pushing
west through the CWA at 3 AM may enhance pre-sunrise convection in
our NW zones, but this feature will only dampen and be of less
significance by daybreak.

With the arrival of the amplifying upper high on Tue, 500 mb heights
will jump a solid 40-50 meters from today. Attendant warming of the
column and subsequent poor mid-level lapse rates should effectively
squash precipitation chances until late week when the high is still
progged to retreat to the Desert SW. Steady height falls, weak NW
flow, and the arrival of a decaying cold front late Wed night/early
Thu all favor an uptick of low PoPs across the Panhandle and
adjacent South Plains. The wildcard from Thu-Sat will be just how
much outflows from episodic storms near the front can drive precip
chances farther south than models say. The joker meanwhile is how
effective the eastern periphery of the upper ridge will be at
warding off these southward-moving storms. For now, PoPs remain
focused mostly over our northern two rows of counties later this
week, before re-orienting N-S off the Caprock later in the weekend
as the upper ridge axis trends more meridional while also nudging
closer to the South Plains.

Temp wise, the heat will shift into overdrive Tue and Wed under
the growing high, before relaxing thereafter as the upper
anticyclone retreats.

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

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