Severe Thunderstorm Warning 221, NWS Lubbock, TX

Area Forecast Discussion
National Weather Service Lubbock TX
624 PM CDT WED JUL 13 2016

.AVIATION...
Although VFR is anticipated, isolated thunderstorms will likely
affect one or more TAF sites this evening. KLBB was currently
experiencing thunder and will continue for another hour or so
until storms move east or dissipate. Chances of storms are
increased near KCDS this evening with a more favorable environment
for thunderstorm development.

&&

.PREV DISCUSSION... /issued 311 PM CDT WED JUL 13 2016/

SHORT TERM...
Another hot day across the region today with mostly sunny skies.
Finally starting to see elevated cumulus developing on top of the
deeply mixed boundary layer over the southern South Plains, with
some hints of additional development along a weak boundary that
stretched southwest to northeast from near Denver City to Childress.
Now that model data have finally arrived after all of the comms
issues this morning, all models generate some convection near or
along this weak boundary.  As usual...coverage remains highly
variable but if the past few days are any indication, most
convection will be isolated.  Deep layer shear is sufficient enough
that any storms that do develop will have a chance to organize and
enough CAPE is present, generally around 1000 J/kg) that a few pulse
severe storms cannot be ruled out.  Did expand coverage of isolated
storms further southwest to include area of developing cumulus and
to keep PoPs in place on both sides of the surface boundary.

Temperatures overnight will depend on what outflow storms can
generate but another fairly strong low-level jet will develop that
will help keep the boundary layer mixed and keep minimum
temperatures within a degree or two of lows recorded this morning.
Tomorrow brings a bit more uncertainty as the models bring a fairly
strong shortwave across the northern Texas Panhandle into southern
Kansas. This will suppress the ridge a bit and help to push a weak
front into the southern Texas Panhandle.  Model time series show
that thickness values do not change much and tendency has been for
temperatures to go above guidance, especially along and south of
frontal boundaries likely due to a combination of compressional
warming and surface wind veering to the southwest ahead of the
front.  MOS guidance came in 3-4 degrees cooler than the forecast
currently has and feel this trend may be in error.  This will keep
highs in the 102-105 degree range and depending on what overnight
lows do, we may need another heat advisory for tomorrow.  Will let
the midnight shift decide and see if guidance temperatures continue
to fall or if temps will hold  closer to where we have been the past
week or so. Jordan

LONG TERM...
Hot weather to continue but some subtle changes in the pattern over
the next few days. Late Thursday, we may see some isolated
thunderstorms along deeper moisture gradient/weak front from NE to
SW across the area. Activity could be aided by weakness in upper
ridge along with weak forcing. kept pops in overnight Thur night
with some weak upper support and boundary possibly fed by low level
jet late. Weak front/boundary may wash out with a return to S/SE BL
flow by late Friday. Looking a little less likely for rain then as
aid from front/upr forcing may be more lacking than previous
thinking. Kept slight chance pops in across a large part of the
forecast area as subsident inversion may be less prominent with some
marginal CAPE available.

Beyond Friday, it looks like its back to hot and dry. Heights begin
to build in again Saturday. Models have been consistent in building
expansive broad upper high northward into Central Plains and mid
Miss Valley toward Monday. This high will amplify farther northward
by Tuesday with mid level easterly flow developing Mon/Tue on south
side of high across West Texas. Despite some cooler temperatures
than our neighbors to the north, heights/thicknesses still suggest
upper 90s to near 100, although may begin to pick up a shallow
cumulus field with some increase in mean RH. Although monsoon
southerly flow may result in increasing convective coverage over the
higher terrain in New Mexico midweek, 500 mb heights will remain
around 594-596 dm which should allow above average temperatures to
continue with only a faint glimmer of a chance for some cooling rain
showers and thunder under this stagnant and subsident high. James

&&

.LUB Watches/Warnings/Advisories...
Heat Advisory until 8 PM CDT this evening for TXZ022>024-028>030-
033>036-039>041.

&&

01

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LUBBOCK TX
321 AM CDT WED JUL 13 2016

TXZ021>044-140830-
PARMER-CASTRO-SWISHER-BRISCOE-HALL-CHILDRESS-BAILEY-LAMB-HALE-
FLOYD-MOTLEY-COTTLE-COCHRAN-HOCKLEY-LUBBOCK-CROSBY-DICKENS-KING-
YOAKUM-TERRY-LYNN-GARZA-KENT-STONEWALL-
321 AM CDT WED JUL 13 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE SOUTH PLAINS...ROLLING
PLAINS AND THE FAR SOUTHERN TEXAS PANHANDLE.

.DAY ONE...TODAY AND TONIGHT

A HEAT ADVISORY IS IN EFFECT THIS AFTERNOON ACROSS PORTIONS OF THE
SOUTH PLAINS AND EXTREME SOUTHERN TEXAS PANHANDLE WHERE AFTERNOON
HIGHS WILL TOP OUT AROUND 105.

ISOLATED SEVERE STORMS WILL BE POSSIBLE THIS AFTERNOON. THE BEST
CHANCES FOR THUNDERSTORM ACTIVITY WILL BE ALONG A LINE FROM LUBBOCK
TO MEMPHIS FAVORING THE MORE NORTHERN LOCATIONS. HAIL TO THE SIZE OF
GOLF BALLS AND 70 MPH WILL BE THE PRIMARY THREAT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

HIGH TEMPERATURES ON THURSDAY WILL BE BETWEEN 103 AND 106 DEGREES
ON THE CAPROCK, AND THEREFORE, A HEAT ADVISORY MAY NEED TO BE
ISSUED.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION NOT ANTICIPATED AT THIS TIME.