Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Austin/San Antonio Texas
752 PM CDT Monday Jul 28 2014
to remove evening probability of precipitation.
showers and thunderstorms along the cold front in central Texas
are dissipating and moving farther east. No longer expect any
convection to move into our County Warning Area this evening. Have removed all
probability of precipitation from the evening forecast. Have adjusted hourly grids to
account for observational trends.
Previous discussion... /issued 641 PM CDT Monday Jul 28 2014/
a weak front will maintain north to northeasterly winds at kaus
through 21z Tuesday...although wind speeds will generally be at or
below 7 kts. Winds at ksat/kdrt/kssf will be light and southeasterly
overnight. In general...all sites including kaus will be VFR through
the forecast period...although MVFR ceilings could be just east of the
I-35 taf sites from 10-15z Tuesday.
Previous discussion... /issued 449 PM CDT Monday Jul 28 2014/
made a slight adjustment to winds generally along and north of
Texas 71 to northeast behind the weak front in line with the
ruc13...then back to southeast late tonight.
Previous discussion... /issued 341 PM CDT Monday Jul 28 2014/
Short term (tonight through Tuesday night)...cold front is just
north of the County Warning Area middle afternoon and moving south. Ruc13 had better
southward placement of the boundary...and following closer to it
through midnight. The boundary will enter far northern counties
between 5 PM and 7 PM...with isolated showers and thunderstorms
along and north of a Llano to Austin to Giddings line. A few
storms could be strong...with gusty winds to 40 miles per hour the primary
threat. Showers and storms should gradually end after sunset.
The boundary will stall over northern areas of the County Warning Area Tuesday
morning...before working back to the north Tuesday afternoon and
evening as surface low deepens to the northwest. Low level
convergence axis will be oriented northwest to southeast Tuesday
near a Llano to Austin to La Grange line. Models slightly drier
with moisture pool than previous runs...with precipitable waters around 1.8
inches...but sufficient for at least isolated showers and storms
across the north-central and northeast County Warning Area Tuesday.
Long term (wednesday through monday)...with the boundary working
back to the north of the County Warning Area by Wednesday...expect mainly dry and
warm conditions with southerly flow. Wednesday will likely be the
warmest day of the week...with many locations near or at the
triple digit mark for highs.
Models continue to indicate upper level ridge amplifying over The
Four Corners Thursday into Friday...but are now quicker with
shortwave in the northwest flow aloft moving through north-central
Texas on Thursday. As a result...the cold front is now quicker
than previous runs with moving back to the south into the ewx County Warning Area.
It now appears the front and broad low level convergence axis will
move into the northern County Warning Area Thursday afternoon...with scattered
convection developing across The Hill Country and central Texas.
With the front continuing south...and support from weak secondary
impulse in the northwest flow aloft...scattered showers and storms
should move south through the Austin/San Antonio corridor and
south of I-10 Thursday evening into Friday morning...tapping into
pool of 2-2.2 inch precipitable waters along and east of I-35 and 1.8-2 inches
west. Storms could back build as far west as the Edwards
Plateau...but highest probability of precipitation are forecast at this time across
central and east. The threat for locally heavy rainfall will be
there...and is mentioned in forecast Thursday night and Friday.
Both the European model (ecmwf) and GFS are also faster with drying that takes
place from northeast to southwest Friday night into Saturday...with
deep moisture axis being pushed along and west of the Rio Grande.
Therefore have trended probability of precipitation back across central zones Friday night
and Saturday...as well as kept forecast dry across the north and
Cooler behind the front...with highs Friday and Saturday ranging
from the upper 80s to around 90 across The Hill Country...lower 90s
along the I-35 corridor...and middle 90s along the Rio Grande and
southern County Warning Area.
Gradual warming early next week...with slightly better moisture
and opportunity for afternoon sea-breeze convection returning
across the southeast zones.
Preliminary point temps/pops...
Austin Camp Mabry 76 98 75 99 75 / 10 30 10 - -
Austin Bergstrom international Airport 74 99 72 99 74 / 10 30 10 - -
New Braunfels Muni Airport 74 100 71 100 74 / - 10 10 - -
Burnet Muni Airport 74 95 73 98 74 / 10 30 10 - 10
del Rio International Airport 79 98 78 101 78 / - - - - -
Georgetown Muni Airport 75 96 73 98 74 / 20 30 10 - 10
Hondo Muni Airport 74 99 71 99 73 / - - - - -
San Marcos Muni Airport 73 98 72 99 74 / - 20 10 - -
La Grange - Fayette regional 76 100 75 98 76 / 10 30 10 10 -
San Antonio International Airport 77 97 75 99 77 / - 10 10 - -
Stinson Muni Airport 75 99 73 99 75 / - 10 10 - -
public service/data collection...32