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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
640 am CDT sun Oct 4 2015

expect VFR ceilings as high clouds stream in from the west today.
There is a slight chance for showers at drt...but probability is
too low to include in taf.


Previous discussion... /issued 400 am CDT sun Oct 4 2015/

Short term (today through monday)...
upper level lows are centered over the central California coast
and the Georgia/Alabama/Florida border region with an upper level
ridge over the northwestern Gulf across eastern Texas. A surface
ridge extends from the Midwest into Texas. In the short term...the
lows move to Southern California and off the South Carolina coast.
A tap of middle and upper level moisture from the Pacific increases
precipitable waters over western Texas to the Pecos Valley. A weak middle level short
wave moves northeast out of Mexico generating showers and
thunderstorms over Mexico into western Texas. Steering flow may
take some of these showers into Val Verde County and have
introduced slight chance probability of precipitation there. Lower daytime temperatures
are expected out west due to thickening clouds. Elsewhere...the
ridge and a drier airmass inhibits rain along with little change
in temperatures.

Long term (monday night through saturday)...
models still disagree on the movement of the California low.
However...they are trending closer in agreement. The upper level
ridge flattens by middle week allowing the low to move to near The
Four Corners region on Wednesday...then the models diverge. The
European model (ecmwf) takes it into northern Mexico while the GFS takes it into
western Texas Thursday and Friday. Surface ridge weakens allowing
increasingly moist flow off the Gulf of Mexico while a moist flow
aloft continues. Upward forcing and precipitable waters increase leading to
showers and thunderstorms moving east into Val Verde County on
Wednesday...spreading east to near I-35 Wednesday night and across
all of south central Texas on Thursday and Friday. Both models are
becoming more consistent in showing an axis of heavier rainfall
across western and central parts of south central Texas due to
precipitable waters approaching 2 inches. As a result...confidence is increasing
on this potential heavier rain event. Will begin to mention this
in the hazardous weather outlook. On Saturday...the GFS opens up
the low with half of the energy lifting off to the northeast into
the Southern Plains and the other half dropping southwest into
Mexico. European model (ecmwf) drifts the low to the west. Upward forcing weakens
and moisture decreases as both models bring a cold front through.
Chances of showers and thunderstorms decrease on Saturday. Expect
a warming trend early into middle week...then a cooling trend late

Beyond this Sunday...the GFS reforms an upper low
over Baja California California where the European model (ecmwf) takes the low. Drier air
filters into our area as ridges at the surface and aloft build
into our area. No rain is expected.


Preliminary point temps/pops...
Austin Camp Mabry 87 64 87 66 91 / 0 0 0 0 0
Austin Bergstrom international Airport 86 61 87 64 91 / 0 0 0 0 0
New Braunfels Muni Airport 91 62 91 66 93 / 0 0 0 0 0
Burnet Muni Airport 85 61 84 63 89 / 0 0 0 0 0
del Rio International Airport 86 68 83 65 91 / 10 10 10 - -
Georgetown Muni Airport 85 61 85 64 90 / 0 0 0 0 0
Hondo Muni Airport 89 63 87 63 92 / 0 0 0 0 0
San Marcos Muni Airport 86 61 86 65 91 / 0 0 0 0 0
La Grange - Fayette regional 86 60 86 66 89 / 0 0 0 0 0
San Antonio International Airport 88 64 88 67 91 / 0 0 0 0 0
Stinson Muni Airport 90 64 90 67 93 / 0 0 0 0 0


Ewx watches/warnings/advisories...



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