Severe Thunderstorm Warning 128, NWS Lubbock, TX

Area Forecast Discussion
National Weather Service Lubbock TX
639 PM CDT Thu Jun 8 2017

.AVIATION...
VFR expected outside of convective activity next 24 hours. A
couple of thunderstorm complexes are extant across the Texas
Panhandle and NERN NM. The activity N of KAMA is likely to follow
a surface boundary and track toward the GTH area late this
evening. Another area NW of KCVS may have more of an impact on
KPVW and KLBB later this evening. Overall, am expecting these
storms to increase in coverage through 05Z...thus have placed
mention of VCTS at KLBB/KPVW. Depending on how the complex N of
AMA evolves, may also need mention at KCDS later this evening.

&&

.PREV DISCUSSION... /issued 615 PM CDT Thu Jun 8 2017/

UPDATE...
Updated to bolster PoPs across the northern zones early this
evening, before expanding this higher potential south overnight.
Also inserted severe mention through 06z given favorable shear
and instability parameters, particularly along the instability
axis stretching from Dumas to Dickens. Improving deep layer shear
atop this instability corridor adds confidence to a southward-
moving MCS after sunset as has been favored by multiple CAMs.
Greatest window for supercells and even a brief tornado threat
should remain in the central Panhandle along a N-S outflow
boundary, before convective outflows consolidate and grow upscale
with time. Convection near Hereford is higher based and displaced
from better instability, but could easily produce downbursts given
downdraft CAPEs of 1500 J/kg.

PREV DISCUSSION... /issued 350 PM CDT Thu Jun 8 2017/

DISCUSSION...
Stable airmass is in place across the northern Rolling Plains
thanks to showers and thunderstorms earlier this morning while we
are starting to see a bit more destabilization across the southern
Rolling Plains into the northern South Plains. High-resolution
models continue to develop an initial round of storms across the
Texas Panhandle and along the edge of the Caprock between
Childress and Silverton later this afternoon and move these
storms south. Then, a second, larger complex of storms develops
across eastern New Mexico and northwestern South Plains then
pushes southeast across the area through early tomorrow morning.
Uncertainty remains high on how things will unfold as models seem
to have had a good handle on the timing of initiation but poor
handle on the coverage the past 3 days or so. Will keep low end-
chance pops in place but no mention of severe at this time until
we can better see where the severe threat will develop. The
majority of the area will not see severe weather and the main
threat of damaging wind will be limited to a few storms and not
the entire area. This will probably require an update to the
forecast in the next 1-3 hours as the meteorological situation
unfolds.

Ridge will start to build over the area tomorrow which will bring
an end to precipitation chances while also bringing an increase in
temperatures. Warmest day will be Saturday when the ridge will
pretty much be overhead and thickness values will be the greatest.
The century mark will be in reach for most of the Caprock as a
southwest wind provides a bit of a downslope component to help
bump up temps a bit more. The Rolling Plains may be saved from 100
degree readings as surface wind remains out of the east which will
help to hold some low-level moisture in place. Flow aloft will
gradually return to the southwest as the ridge breaks down some as
a storm system moves onshore across the Pacific Northwest the
first part of next week. This will help temperatures to continue
to fall a few degrees each day next week to the low 90s for the
South Plains and mid 90s for the Rolling Plains. Isolated
thunderstorms can also not be ruled out as early as Monday
afternoon as a weak dryline sets up under southwest flow aloft.
Forecast has PoPs for the entire 12 hour periods from the grids
but in reality the window for storms will be the afternoon and
early evening hours, not the entire period.

Jordan

&&

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

99/99/26

Hazardous Weather Outlook...UPDATED
National Weather Service Lubbock TX
629 PM CDT Thu Jun 8 2017

TXZ021>044-092330-
Parmer-Castro-Swisher-Briscoe-Hall-Childress-Bailey-Lamb-Hale-
Floyd-Motley-Cottle-Cochran-Hockley-Lubbock-Crosby-Dickens-King-
Yoakum-Terry-Lynn-Garza-Kent-Stonewall-
629 PM CDT Thu Jun 8 2017

This Hazardous Weather Outlook is for the South Plains...Rolling
Plains and the far Southern Texas Panhandle.

.DAY ONE...Tonight

Severe thunderstorms are expected to develop and spread south from
the Texas Panhandle this evening, before organizing into a complex
of storms across the outlook area after sunset. Large hail to golf
ball size, wind gusts to 70 mph and heavy rain will all be
possible with the strongest of these storms.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

A dryline may focus severe thunderstorm development Monday
through Wednesday.