Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Austin/San Antonio Texas
624 am CDT Monday Jul 6 2015
Update...12z aviation discussion below.
Aviation...MVFR stratus ongoing early this morning across
portions of the area including the Sat/aus terminals. Can not
rule out Sat and some locations in The Hill Country lowering into
IFR range temporarily 12z-14z. Stratus is expected to mix out
15z-17z with VFR scattered-broken cumulus field through the afternoon at Sat/aus
areas. Model guidance showing wind gusts around 25 kts again this
Previous discussion... /issued 357 am CDT Monday Jul 6 2015/
Short term (today through Tuesday night)...
a middle to upper level trough moves into the plains today and
lingers over western Texas into The Big Bend through Tuesday
night. A plume of deeper moisture pools across The Trans Pecos
into the western Edwards Plateau with precipitable waters of 1.7 to 2 inches.
Expect isolated to scattered showers and thunderstorms across the
Edwards Plateau to the Rio Grande. The deepest moisture is on
Tuesday and some heavier rains are possible. A middle to upper level
ridge over the Gulf of Mexico will impact the remainder of south
central Texas. Moisture decreases with precipitable waters of 1.4 to 1.6 inches
and subsidence increases with no probability of precipitation mentioned. Little or no
temperature change is expected.
Long term (wednesday through sunday)...
middle to upper level trough lifts out to the northeast on Wednesday
with isolated showers and thunderstorms possible Val Verde County.
Middle to upper level ridge over the Gulf of Mexico into southeastern
states shifts west to over Texas Thursday through Saturday and
northwest to southern rockies by Sunday. Strong subsidence...warm
middle level capping temperatures and a drier airmass with precipitable waters of 1
to 1.5 inches keep probability of precipitation out of the forecast. There is a potential
for a brief incursion of deeper moisture with precipitable waters up to 1.8 inches
Friday into Saturday near the coastal plains. This would allow
seabreeze to generate isolated showers and thunderstorms there.
Models have been inconsistent on this and will not mention probability of precipitation
for now to await some consistency and only have silent 10s. Only a
very slow warming trend is anticipated boundary layer temperatures
and lower level thicknesses only slightly increase along with
residual soil moisture from the Spring and early Summer rains. May
see temperatures approach 100 by the weekend across southern parts
of the Rio Grande plains.
Beyond this forecast...models show the ridge building in the west
and a deepening trough in the east allowing a very rare middle July
cold front to move into central Texas the middle of next week
creating a possibility of showers and thunderstorms.
Preliminary point temps/pops...
Austin Camp Mabry 92 76 92 76 92 / - - - - -
Austin Bergstrom international Airport 91 77 91 75 92 / - - - - -
New Braunfels Muni Airport 92 76 92 74 93 / - - - - -
Burnet Muni Airport 90 74 89 74 91 / - - - - -
del Rio International Airport 93 77 94 77 95 / 10 20 20 20 10
Georgetown Muni Airport 91 76 90 75 93 / - - - - -
Hondo Muni Airport 91 75 92 75 92 / - - - - -
San Marcos Muni Airport 91 76 91 75 92 / - - - - -
La Grange - Fayette regional 92 76 92 77 92 / - - 10 - -
San Antonio International Airport 91 76 91 76 92 / - - - - -
Stinson Muni Airport 91 76 92 75 92 / - - - - -