Area forecast discussion
National Weather Service Austin/San Antonio Texas
815 PM CDT sun may 19 2013
Update...
dryline along a Langtry to just east of Sonora line moving back
west. The few moderate cumulus that developed along it have since
dissipated. Airmass is too capped with weak moisture convergence
and have removed isolated probability of precipitation for this evening. Re-established
sensible weather trends for tonight into Monday morning. Remainder
of south central Texas forecast is on track. 18z models still show
isolated to scattered showers and thunderstorms Tuesday afternoon
into Wednesday. A weakening surface boundary moves into south
central Texas while an upper level trough moves across Texas. High
convective available potential energy...ample shear...and strong instability suggest a possibility
of a few strong to severe thunderstorms late Tuesday afternoon
into evening.
&&
Previous discussion... /issued 613 PM CDT sun may 19 2013/
Aviation...
scattered/broken clouds about 5kft are depicted by visible satellite photos
along i35 corridor late this afternoon. These clouds will
dissipate overnight. However...lower ceilings will develop after 05z
to 17z Monday with MVFR conditions prevailing for this period
across the i35 terminals. After 17z Monday...ceilings will lift to VFR
category for the remainder of the forecast cycle. Southerly flow
will be dominating through the period with wind speeds of 10 to
17 knots with occasionally gusts up to 25 knots. Across kdrt...VFR
conditions to prevail for the entire forecast period.
Previous discussion... /issued 308 PM CDT sun may 19 2013/
Short term (tonight through Monday night)...
widespread cumulus field across S central Texas/Hill country region
this afternoon. The cumulus were becoming more agitated across the
western/northwestern Hill Country along the dry line and will continue
isolated evening storms across this area. Storm Prediction Center has also brought the
slight risk area down into the area...so have updated the severe weather potential statement. This
convection will end with the loss of heating not long after
sunset. Otherwise little change through Monday night with the dry
line setting off isolated convection across the western County Warning Area Monday
afternoon and evening. Continued unseasonably warm and breezy.
Long term (tuesday through sunday)...
best chances for any rain this package continue to be late Tuesday
into early Wednesday as an upper air trough and a surface cold
front arrive in central Texas during maximum heating late Tuesday afternoon.
Isolated-scattered thunderstorms developing over north/central Texas
Tuesday afternoon and dropping southward across the County Warning Area Tuesday
evening. Storm Prediction Center continues to have much of the County Warning Area in a slight risk
area. With upper air support and surface convergence along the
front/outflow boundaries...this convection should continue well past
sunset into the overnight hours. Decreasing probability of precipitation on Wednesday...as
lingering surface boundaries and cool northwesterly flow aloft could result
in isolated storms during the day. The remainder of the forecast
for Thursday through Sunday looks unseasonably warm and humid...with
little chance for any significant convection...so have gone with
silent 5-10 percent probability of precipitation and warmer than guidance temperatures.
&&
Preliminary point temps/pops...
Austin Camp Mabry 73 94 73 94 72 / - - 10 30 40
Austin Bergstrom international Airport 72 93 72 94 71 / - - 10 30 40
New Braunfels Muni Airport 71 94 71 94 70 / - - 10 20 40
Burnet Muni Airport 71 93 71 92 70 / - 10 20 30 40
del Rio International Airport 76 100 75 99 75 / - 10 20 10 20
Georgetown Muni Airport 72 93 71 93 71 / - - 10 30 40
Hondo Muni Airport 73 95 72 96 72 / - - 10 20 30
San Marcos Muni Airport 73 93 72 93 71 / - - 10 30 40
La Grange - Fayette regional 75 93 75 93 74 / - - 10 20 30
San Antonio International Airport 73 95 73 94 72 / - - 10 20 30
Stinson Muni Airport 73 95 73 95 73 / - - 10 20 30
&&
Ewx watches/warnings/advisories...
none.
&&
$$
Mesoscale/aviation...17
synoptic/grids...04
public service/data collection...33
