Area Forecast Discussion
Issued by NWS San Angelo, TX

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS64 KSJT 190449

1149 PM CDT FRI APR 18 2014

/06Z TAFS/

Models this cycle continue to develop MVFR ceilings across most of
West Central Texas later tonight. My only concern is the higher
clouds may delay this development. However, my confidence isn`t high
enough to deviate from timing we had in the previous terminals.




/00Z TAFS/

Expect MVFR conditions to develop after 10z at all TAF sites
except KABI. Model guidance does hint at the possibility of MVFR
conditions making progress into the KABI terminal. However,
confidence in this occurring was not high enough to include in the
TAFs at time time. Look for VFR conditions to return to all
terminals after 17z.



(Tonight and Saturday)

Overcast low clouds earlier today have lifted and become mostly
broken in coverage this afternoon. Cloud bases have lifted from just
a few hundred feet in some areas to mostly above two thousand feet
this afternoon.  That trend will continue into the early evening
hours.  There will in an increase in high cirrus clouds moving in
from the west near sunset. Low clouds are expect to form again by
early Saturday morning from San Angelo southward including Junction,
Sonora and Brady. Five to 10 mph east winds today are likely to
become light and variable in low lying areas overnight.  Winds will
slowly shift around and blow from the southeast and then from the
south by midday Saturday increasing to 12 to 18 mph by Saturday
afternoon. This wind increase is in association with an upper level
low pressure circulation currently near San Diego California that is
moving east quickly.  Despite this upper level circulation nearing
the area, rain changes remain low through Saturday night despite
increases in cloudiness and relative humidity.


(Saturday Night through Friday)

The main highlights in the long term forecast are the potential for
showers and thunderstorms this weekend, followed by above normal
temperatures for much of next week. A potent upper level trough
currently over California, will move west and approach West Central
Texas this weekend. A disturbance is forecast to move across West
Texas Saturday afternoon/evening. High resolution models in addition
to the most of the operational models, develop convection across
much of the Permian Basin down to the Trans Pecos region, then
slowly move it west through the early evening hours. Most of the
models slowly weaken the convection as it moves into our western
counties, before dissipating it by mid evening. Although this is
very plausible, if the convection can get a cold pool going, I would
not be surprised to see it make more progress into our area. For
now, I have kept PoPs in the low end chance category, given the
uncertainty, and will continue to monitor. Modest instability and
0-6 KM Bulk Shear values of 35 to 45 knots, could yield a few strong
to severe thunderstorms.

On Sunday, the base of the aforementioned upper level trough will
swing across the Southern Plains, with a dryline located across West
Texas. West Central Texas will remain in the moist sector, with
decent instability developing during the afternoon/early evening
hours. I expect isolated to scattered showers and thunderstorms to
develop, with the favored region being the Big Country. Decent
instability will be in place, and a few strong to severe storms will
be possible. At this time, I expect the main threats to be large
hail and strong gusty winds. Any convection that does develop will
linger into the evening hours, with most moving east of the area
after midnight.

A weak cold front will move into the Big Country Monday morning,
then slow down as it approached the the Interstate 10 corridor.
Isolated to scattered showers and thunderstorms will be possible
during the afternoon/evening along the front, mainly south of a San
Angelo to Brownwood line. For now, I have kept PoPs below 15
percent, but these may need to be raised on future shifts. The rest
of the week will be characterized by above normal temperatures, with
highs mainly in the 90s and lows generally in the 60s. Isolated
dryline convection will be possible late Wednesday and Thursday, but
given the uncertainty this far out, I have opted to leave out any
mention from the grids at this time.


A combination of fairly moist air and light winds will keep the fire
weather damage low through Saturday morning. Fire weather
conditions will become elevated Saturday afternoon as a consequence
strengthening south and southeast winds of 12 to 18 knots with
higher gusts combined with existing very dry vegetation.



Abilene  74  58  77  59  80 /  10   5  10  30  30
San Angelo  78  58  79  58  82 /  30   5  10  30  30
Junction  79  60  78  58  80 /  20   5  10  20  20




Huber is the U.S. government's official web portal to all federal, state and local government web resources and services.