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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
1146 PM CDT Tuesday Jul 29 2014

Aviation...
expect VFR and light southeast winds through 17z. A tightening
pressure gradient and daytime mixing will produce winds of at least
10g20kt from 17z to 02z Thursday...then sustained 10-15 kts at the
I-35 sites through 09z Thursday. We introduced an MVFR ceiling at 015
above ground level after 09z Thursday for the extended 30-hour tafs at kaus and
ksat...but expect the same for kssf.

&&

Previous discussion... /issued 750 PM CDT Tuesday Jul 29 2014/

Update...
to remove convection.

Discussion...
showers and thunderstorms have dissipated...so have removed the
mention of convection before midnight. Adjusted hourly grids to
account for observational trends. Otherwise...forecast looks on
track.

Previous discussion... /issued 637 PM CDT Tuesday Jul 29 2014/

Aviation...
an outflow boundary has already passed kaus and will pass through
ksat and kssf between 0130z and 02z. Look for a wind shift to
04015g25kt right after passage...then settling down 06010kt or so
for a few hours. More typical south-southeast winds will re-
establish by 04-06z and continue through 14z. Daytime heating on
Wednesday and a tightening pressure gradient will increase winds
to at least 10g20kt area wide...with slightly stronger winds just
to the east of the Balcones Escarpment at kaus.

Previous discussion... /issued 333 PM CDT Tuesday Jul 29 2014/

Short term (tonight through Wednesday night)...
scattered convection over central Texas this afternoon shows
little movement potential through this evening...leaving outflows
to be the focal points for new convection. While precipitable water at values are
currently pooled at around 2 inches over our NE counties...the
outflows and stable middle level air should help to disperse some of
the pooled moisture...so will follow the model consensus that
depicts increasing stability and a warming trend for maximum temperatures
Wednesday. Late Wednesday night a shortwave moving through the
Panhandle into Oklahoma is shown to carve out increasing northerly
flow in its wake over northwest Texas leaving an opportunity for isolated new
convection to form over central Texas toward daybreak Thursday.

Long term (thursday through tuesday)...
late in the day Thursday...the increasingly meridional flow aloft
should push additional clouds and moisture into south central Texas
to put a Dent in the Summer heat. A frontal boundary is shown by
model consensus to hold off moving into south central Texas until
Friday morning...but the ingredients should be in place for an mesoscale convective system
to pull the wind shift southward Thursday night. With the GFS
model hesitant to show more widespread coverage initially and then
spreading enhanced probability of precipitation over a broad time period lasting into
Monday...will keep conservative on probability of precipitation for now...but expect the
slightly better rain chances to be Thursday night through Friday
night. The European model (ecmwf) has been more Adamant in showing a more
stabilizing cold frontal passage with diminished rain chances by
Friday afternoon. A blend with the wetter GFS was chosen Friday
through Monday since the northerly flow pattern aloft is usually
good for at least one surprise round of convection.

&&

Preliminary point temps/pops...
Austin Camp Mabry 74 97 74 94 74 / 10 10 20 30 30
Austin Bergstrom international Airport 71 98 72 93 72 / 10 10 20 30 30
New Braunfels Muni Airport 72 98 72 94 73 / 10 10 10 20 30
Burnet Muni Airport 73 96 72 91 71 / 10 10 20 30 20
del Rio International Airport 78 103 78 98 78 / - - - 10 20
Georgetown Muni Airport 74 96 73 92 72 / 10 10 20 30 30
Hondo Muni Airport 72 100 72 95 73 / 10 - - 10 20
San Marcos Muni Airport 72 97 72 93 73 / 10 10 10 20 30
La Grange - Fayette regional 75 97 75 94 75 / 10 10 10 30 30
San Antonio International Airport 75 98 76 94 76 / 10 - 10 20 30
Stinson Muni Airport 73 100 74 95 75 / 10 - 10 10 30

&&

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

$$

Mesoscale/aviation...26
synoptic/grids...05

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