Hail in Texas, May 1, 2019

Area Forecast Discussion
National Weather Service Lubbock TX
1224 PM CDT Wed May 1 2019

.AVIATION...
MVFR deck at CDS is set to scatter out in another hour or so,
while LBB and PVW remain VFR all day. Primary storm chances
this afternoon and evening will remain well south of CDS, however
a threat for nighttime storms exists at CDS along and behind a
cold front pushing south ahead of widespread MVFR and IFR
stratus. This storm threat is too marginal for further mention at
this time, but CDS is likely to collapse to IFR again in stratus
and some fog overnight. Thereafter, a cold front before daybreak
will usher in widespread low ceilings and gusty north winds to
all terminals.

&&

.PREV DISCUSSION... /issued 402 AM CDT Wed May 1 2019/

DISCUSSION...

Long wave upper level trough stretched across the western CONUS will
keep the FA under SWRLY flow today.

Morning surface analysis continues to show a stalled boundary
lingering near our southern row of counties with the dryline set up
from a Brownfield to Littlefield to Dimmitt line. This afternoon the
dryline will slowly migrate eastward but, not as far east as
previously expected. Hi-res models indicate that backing winds in
the warm sector will force the dryline to roughly stall from a Post
to Silverton line. Thus, isolated to scattered convection is
expected where the dryline meets the surface front (across our far
SE counties). Stability indices shows MUCAPES east of the dryline of
2000-3000 J/kg by 21Z with mid-level lapse rates of 7-7.5 C/km, 0-
6km shear values of 40kts and helicities of ~100 m^2/s^2. Therefore,
primary threats with storms that become severe will be large hail
and damaging wind gusts. Given such low helicity values tornadoes do
not seem as big a risk as previous days. It should be stated that if
the stalled front should push further south or the dryline should
push further east convection could develop just south and east of
the FA and gradually move into our area.

Overnight the the dryline will push east as drier air is advected in
its wake. Low level moisture will still be hanging around our far
eastern column of counties thus, fog may be possible across the far
eastern Rolling Plain tomorrow morning. A cold front will slide
through the FA early Thursday morning. Depending on how far south
the front settles will determine our convection chances for Thursday
but, it does appear that by Thursday afternoon/evening convection
could develop along the front and across our southern counties.
While instability will be weaker, lift from an upper level short
wave could help storms develop and those that do could become
strong. The other impact Thursday's front will have will be below
normal temperatures Thursday and Friday.

Friday through the weekend the dry line settles across the TX/NM
border opening the door for moisture to flow up and into our FA. A
weak cold front tries to push into the CWA on Friday but appears to
stall across the northern counties. Embedded shortwaves in the upper
level zonal flow could help kick off convection in the afternoon.
For now this is something that will need watching. We will continue
with low end PoPs. We retain chances for convection Saturday  and
Sunday under a dirty upper level ridge.

Monday into Tuesday a deep upper level Pacific low pressure system
will begin to approach SOCAL. This will once again place us under
SWRLY flow aloft, open the door for low level moisture to traverse
across the FA and keep dryline convection in the forecast for Monday
and Tuesday.

&&

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

93

Hazardous Weather Outlook...UPDATED
National Weather Service Lubbock TX
1129 AM CDT Wed May 1 2019

TXZ021>044-020430-
Parmer-Castro-Swisher-Briscoe-Hall-Childress-Bailey-Lamb-Hale-
Floyd-Motley-Cottle-Cochran-Hockley-Lubbock-Crosby-Dickens-King-
Yoakum-Terry-Lynn-Garza-Kent-Stonewall-
1129 AM CDT Wed May 1 2019

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

.DAY ONE...This Afternoon and Tonight

Severe thunderstorms are possible across the southern Rolling
Plains this afternoon and evening. Strong instability and
moderate wind shear will support the development of supercell
storms capable of producing hail to over 3 inches in diameter,
wind gusts to 70 mph, and torrential rainfall that may create some
flooding. Although low level wind shear is weak, a tornado threat
is possible especially near any outflow boundaries.

Overnight, a cold front may trigger severe storms in the far
southeast Panhandle. Large hail around golfball size is possible
with these overnight storms.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

Additional bouts of severe thunderstorms are possible this
weekend through early next week.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be requested for this afternoon.