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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
327 PM CDT Sat Apr 19 2014

Short term (tonight through Sunday night)...
low level moisture continues to increase across south central
Texas this afternoon as surface high pressure ridge over the
eastern half of the nation pushes to the northeast. Also...
middle to upper level moisture from the eastern Pacific persists
across the area as the sub-tropical jet moves across the southern
states/Gulf of Mexico area. Isolated showers and even an isolated
thunderstorm is possible across Val Verde County through late this
afternoon as an upper level short-wave moves from northeast Mexico
into central Texas. This activity could expand to the east this
evening affecting portions of the southern Rio Grande plains and
Edwards Plateau. Rainfall amounts are expected to be light or few
hundredths of an inch at most. Overnight lows will range from the
upper 50s across The Hill Country to middle 60s in southern Rio
Grande plains.

Another but stronger upper level short-wave trough is forecast to
push across central Texas midday/early afternoon Sunday. With surface
dewpoints in the upper 50s to lower 60s and the passage of the
upper wave (for upper level support)...expect a slight chance of
showers and thunderstorms across most areas with better chances
for thunderstorms out west...especially west of a Rocksprings to
del Rio line. Some of these storms could become strong to even
severe in the afternoon/early evening with large hail and damaging
winds as main hazards. Once again...quantitative precipitation forecast values are anticipated to
be light or from a trace to several hundredths of an inch.



&&

Long term (monday through saturday)...
an upper level low pressure system over southwest Arizona this
afternoon is forecast to push to the northeast and into the
Central Plains by Monday. At the surface...a weak cold front is
expected to push across south central Texas around midday/early
afternoon with dewpoints in the lower to middle 60s. At the same
time...a vorticity maximum is expected to be moving at the bottom of the
upper trough with area forecast soundings showing cape of 2000 to
3000 j/kg and lifted index values of -6 to -7. With these atmospheric
conditions...any storm that does develop has the potential to become
strong to severe. As of now...Storm Prediction Center day3 severe thunderstorm outlook
has The Hill Country (northeast of a Rocksprings to Kerrville to
Georgetown line) with a slight risk of severe thunderstorms. Large
and damaging winds are expected to be the main hazards for this
event.

Storms will come to an end Monday night as the cold front pushes
across the area and upper level northwest winds develop. Tuesday and
Wednesday of next week expect typical Spring days over the area
with 90s over the west and upper 80s east of Highway 281. Another
upper level trough is forecast to push across the area on Thursday
for a chance of rain mainly over the I-35 corridor.

&&

Preliminary point temps/pops...
Austin Camp Mabry 59 79 62 83 64 / 10 20 10 20 20
Austin Bergstrom international Airport 56 79 60 83 62 / 10 20 10 20 20
New Braunfels Muni Airport 57 79 61 84 61 / 10 20 10 20 20
Burnet Muni Airport 59 76 62 82 63 / 10 20 10 30 20
del Rio International Airport 64 81 66 88 66 / 30 30 10 20 10
Georgetown Muni Airport 58 78 62 82 64 / 10 20 10 20 20
Hondo Muni Airport 63 81 65 88 65 / 10 20 10 20 10
San Marcos Muni Airport 57 78 60 83 61 / 10 20 10 20 20
La Grange - Fayette regional 59 81 62 82 63 / 10 20 10 20 20
San Antonio International Airport 61 79 63 85 64 / 10 20 10 20 20
Stinson Muni Airport 61 81 63 87 64 / 10 20 10 10 20

&&

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

$$

Mesoscale/aviation...09
synoptic/grids...17
public service/data collection...32