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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
712 PM CDT Thursday Aug 25 2016

Update...
updated the short-term pops (through 10 pm) to reflect the ongoing
convection in the eastern County Warning Area. Most of this activity should die
off by 10 PM with the loss of daytime heating and the beginning of
the stabilization of the boundary layer. Some lingering showers
may be possible as activity weakens beyond 10 PM. Only other
changes were to the hourly grids based on current trends around
the area.

&&

Previous discussion... /issued 658 PM CDT Thursday Aug 25 2016/

Aviation.../00z tafs/
isolated to scattered showers and thunderstorms that are 15-20
miles east-southeast of aus will slowly push west as they dissipate. Thus,
have included thunderstorms in the vicinity after 0115 UTC and a slight easterly wind shift
for aus to cover these storms and their outflows even though they
should weaken before reaching the terminal. VFR conditions are
expected otherwise until MVFR ceilings move in around 7-8z at
Sat/ssf, 11z at aus, and 12z at drt. VFR conditions should return
by 15z for the I-35 sites and 17z for drt with southeast 5-10 knot winds
tomorrow. Thunderstorms may affect the I-35 sites tomorrow
afternoon, but confidence is too low to include at this time.

Previous discussion... /issued 252 PM CDT Thursday Aug 25 2016/

Short term (tonight through Friday night)...
showers and thunderstorms were developing in the coastal plains
counties as of 230pm. Visible satellite imagery depicts an area of
instability from the I-35 corridor eastward. Rap mesoanalysis
depicts this area at 2.5-3.5 kj/kg of SBCAPE, better pwats, and
850 mb weak moisture convection. Hi-res models only hang on to
this convection through 23-00z and quickly dissipates everything
by nightfall. Did increase afternoon pops to reflect current
convection.

Tomorrow's forecast looks to be similar to today's however
convection could push a bit farther west, perhaps reaching the
Escarpment in the afternoon hours. A Gulf TUTT low will very
slowly migrate westward and be positioned just off the Galveston
Bay. This will serve to focus lifting and further advect deep
moisture into the County Warning Area moving into Friday night.

Long term (saturday through thursday)...
the aforementioned TUTT low will continue to inch westward onshore
an increase pop chances by Sunday. Models currently do not
generate quantitative precipitation forecast that raises any eyebrows, likely due to the weak
nature of the TUTT. However, pwats will gradually increase to back
over 2 inches in the east Sunday afternoon and while widespread
heavy rain doesn't look likely at the moment...locally heavy rain
will be a possibility each day through most of the week. And if
multiple days/rounds of heavy rain impact the same areas in the
east, could see some isolated spots seeing 2-4 inches of rain
through next Friday.

By late in the week, the main upper ridge broadens and drier air
filters back into the region. Likely raising highs and lowering
pop chances by next weekend.

&&

Preliminary point temps/pops...
Austin Camp Mabry 74 90 73 90 73 / 20 30 10 40 10
Austin Bergstrom Intl Airport 74 90 72 89 72 / 20 30 10 40 10
New Braunfels Muni Airport 75 90 72 90 72 / 10 30 10 40 10
Burnet Muni Airport 73 89 72 89 71 / 10 30 10 30 10
del Rio Intl Airport 74 94 74 94 74 / 10 10 - 20 -
Georgetown Muni Airport 74 90 72 89 72 / 10 30 10 30 10
Hondo Muni Airport 73 92 72 91 72 / - 20 - 20 10
San Marcos Muni Airport 73 90 72 89 72 / 20 30 10 40 10
La Grange - Fayette regional 75 90 74 89 74 / 30 40 10 40 20
San Antonio Intl Airport 76 91 73 90 73 / 10 20 10 30 10
Stinson Muni Airport 75 92 74 92 74 / 10 20 10 30 10

&&

Ewx watches/warnings/advisories...
none.
&&

$$

Mesoscale/aviation...LH
synoptic/grids...Hampshire
public service/data collection...30

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