Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Austin/San Antonio Texas
1141 am CDT Sat Sep 20 2014
starting to see a few showers pop up west of the San Antonio
metropolitan area. Still expecting about a 30 to 40 percent coverage of
activity today for most of the area. The higher coverage should be
west of Highway 281. This morning the GOES sounder showed the
higher precipitable waters across the west and the del Rio radiosonde observation had an observed
precipitable water that jumped up to 2.1 inches. Will mention locally heavy
rainfall in the grids and continue to highlight in graphicasts and
the severe weather potential statement.
Previous discussion... /issued 632 am CDT Sat Sep 20 2014/
moisture continues across the region. Should once again see
scattered convection this afternoon across the area. Due to timing
issues for convection have left out of kdrt taf. Did include a
tempo group for the I-35 sites for middle to late afternoon
convection. Drier air will be entering the region later today
through Sunday and will continue to see a further decrease in
convection. Will see IFR/MVFR ceilings through 15z-16z this
morning then VFR. Look for MVFR ceilings to return between 09z-11z
Sunday morning. Winds will be east/southeast at 7-10 knots today then light
and variable after 07z tonight.
Previous discussion... /issued 322 am CDT Sat Sep 20 2014/
Short term (today through sunday)...
plenty of moist air still in place to produce isolated light showers
across the area early this morning. While the remnants of Pacific
storm Odile and moist air from the Gulf and Pacific storm Polo
are still in the vicinity...precipitable water has decreased significantly across
our area... especially over the western 1/3. This doesn/T mean an
end to the rain...but another step down in coverage and intensity
from Friday. Many more locations should remain dry today or
receive 1/10 inch or less of rain. However...isolated downpours of
1 to 2 inches are still possible...especially in The Hill
Country...where convection allowing mesoscale models point toward
a peak in thunderstorm coverage and intensity by early afternoon.
Look for another step down in convection tomorrow as drier air
continues to filter in from the northeast. Probability of precipitation on Sunday should
mostly be focused on the Rio Grande plains.
Long term (sunday night through friday)...
a weak cold front washes out just north of our area on Monday...
but drier and slightly cooler air should continue to filter into
south central Texas. We decided to place small probability of precipitation for Monday
and Tuesday afternoons in the northeast and east coastal plains as
the GFS/European model (ecmwf) indicate enough lift along the remnant of the front
Monday...and a weak shortwave trough moving through North Texas
on Tuesday...to produce isolated storms. Look for dry conditions
Wednesday and Thursday as ridging builds over the southwestern
states...then isolated storms for mainly the Rio Grande and
coastal plains Friday into the weekend as moist Gulf flow returns
and the ridge is broken down by a deep longwave trough over the
Preliminary point temps/pops...
Austin Camp Mabry 89 71 91 69 91 / 30 20 - - 20
Austin Bergstrom international Airport 89 69 92 68 91 / 30 20 - - 20
New Braunfels Muni Airport 91 71 92 69 93 / 30 30 10 - 10
Burnet Muni Airport 89 70 90 69 90 / 30 20 10 - 20
del Rio International Airport 90 74 88 71 88 / 30 30 20 20 -
Georgetown Muni Airport 89 70 91 69 91 / 30 20 - - 20
Hondo Muni Airport 92 72 92 68 93 / 30 30 20 10 -
San Marcos Muni Airport 89 70 91 68 91 / 30 20 10 - 20
La Grange - Fayette regional 91 71 92 70 92 / 30 20 - - 20
San Antonio International Airport 91 73 92 71 92 / 30 30 10 - 10
Stinson Muni Airport 92 73 92 70 93 / 30 30 10 - -
public service/data collection...33