Severe Thunderstorm Warning 278, NWS San Angelo, TX

Area Forecast Discussion
National Weather Service SAN ANGELO TX
610 PM CDT SAT SEP 17 2016

.AVIATION...
/00Z TAFS/

Isolated to scattered thunderstorms are possible this evening
across the western Concho Valley and western Northern Edwards
Plateau. However, confidence is low to add VCTS at the KSJT/KSOA
terminals and will continue to monitor radar trends. Otherwise,
expect mainly VFR conditions the next 24 hours. The winds will be
generally from the south at 5 to 10 knots.

&&

.PREV DISCUSSION... /issued 324 PM CDT SAT SEP 17 2016/

SHORT TERM...
(Tonight and Sunday)

We will continue a slight chance to chance for showers and
thunderstorms tonight into Sunday.

We have a couple of boundaries laying across the CWA that were
left over from last night's convection. The more prominent of the
two currently stretches from southwestern Irion County, southeast
through Schleicher County into northwestern Kimble County before
becoming rather diffuse. The second boundary is harder to find on
radar imagery, but can be seen in satellite data just south of
I-20 in our Big Country region. Of the two, the former appears to
be most likely to result in convection this afternoon/evening as
it has really tightened up as of 3 PM, and the atmosphere has been
stabilized around the I-20 boundary. High resolution models show
convection developing off of this southern boundary during the
evening hours as well. Thus, have increased PoPs slightly farther
south in our CWA to account for possible showers and thunderstorms
developing along this boundary. Thunderstorms are currently
developing farther west in southeastern NM, and may develop into
an eastward moving MCS, affecting the northern 2/3 of the area
later this evening as well. Steering flow is relatively weak, so
in addition to the potential for some of the stronger storms to
produce large hail, damaging winds, and dangerous lightning,
locally heavy rainfall would also be a concern with any
thunderstorms that develop.

An MCS may also develop later tonight to our northwest, then move
southeast into our area after midnight into Sunday morning. If
this second MCS does move into the area late tonight, it is
expected to weaken after 12Z as it moves southeast. Have kept
highest PoPs in the Big Country tonight, with only Slight Chance
PoPs Sunday for areas east of Haskell to Junction line.

Temperatures will continue to be warmer than normal, lows tonight
in the upper 60s/near 70, and highs Sunday in the upper 80s to mid
90s.

20

LONG TERM...
(Sunday night through Saturday)

An upper ridge will expand northeast from Mexico next week, with
subsidence ending rain chances Monday into Friday. A large scale
upper trough, however, will move into the Central U.S. Friday.
This will weaken the upper ridge and possibly induce a cold front
to move through Saturday afternoon or night. Have rain chances in
the 20 to 40 percent range Saturday/Saturday night, with the best
potential in eastern zones.

Until the front comes through Saturday, above normal temperatures
are in store next week, with highs in the lower to mid 90s and
lows in the upper 60s to lower 70s. Saturday, with the front
moving in late, it will still be warm, with highs in the upper
80s.

&&

.PRELIMINARY POINT TEMPS/POPS...
Abilene 	 71  93  73  95 /  30  20   5   5
San Angelo 	 71  96  71  96 /  30  10   5   5
Junction 	 72  96  71  96 /  20  10   5  10
Brownwood 	 71  94  71  96 /  20  20   5   5
Sweetwater 	 70  92  72  94 /  30  10   5   5
Ozona      	 71  93  71  94 /  20   5   5   5

&&

.SJT Watches/Warnings/Advisories...
None.
&&

21

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN ANGELO TX
332 PM CDT SAT SEP 17 2016

TXZ049-054-064>066-071>073-076>078-098-099-113-114-127-128-139-
140-154-155-168>170-182045-
FISHER-NOLAN-STERLING-COKE-RUNNELS-IRION-TOM GREEN-CONCHO-
CROCKETT-SCHLEICHER-SUTTON-HASKELL-THROCKMORTON-JONES-SHACKELFORD-
TAYLOR-CALLAHAN-COLEMAN-BROWN-MCCULLOCH-SAN SABA-MENARD-KIMBLE-
MASON-
332 PM CDT SAT SEP 17 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WEST CENTRAL
TEXAS.

.DAY ONE...THIS AFTERNOON AND TONIGHT

SCATTERED THUNDERSTORMS WILL BE POSSIBLE THROUGH TONIGHT ACROSS
WEST CENTRAL TEXAS. DANGEROUS LIGHTNING...GUSTY WINDS...AND
LOCALLY HEAVY RAINFALL WILL CONTINUE TO BE THE PRIMARY THREATS.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

ISOLATED THUNDERSTORMS WILL BE POSSIBLE SUNDAY...MAINLY EAST OF A
HASKELL TO JUNCTION LINE...WITH DANGEROUS LIGHTNING AND HEAVY
RAINFALL THE MAIN THREATS. DRY CONDITIONS WILL RETURN ON MONDAY
AND CONTINUE THROUGH THE UPCOMING WEEK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED AT THIS TIME.