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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
657 PM CDT Monday Sep 15 2014

Aviation...
high pressure should hold back cloud cover to VFR through at least
07z despite a good amount of available moisture and southeasterly low level
winds. Some isolated sea-breeze convection forming over the
coastal Bend is suggested to shift focus to the I-35 taf sites by
the finer res model data toward midnight...but with slow storm
motions noted...will leave this feature out of the tafs for now.
Abundance of high clouds could delay the MVFR ceiling development late
tonight and will look at a possible update for this shift as 00z
model data arrives. Late in the period...a weak surface low moves
onshore into deep S Texas and northwest flow develops aloft...leaving more
favorable conditions for convection in the afternoon and early
evening.

&&

Previous discussion... /issued 305 PM CDT Monday Sep 15 2014/

Short term (tonight through Tuesday night)...
isolated showers continue over The Hill Country and Edwards
Plateau...but amounts are negligible and the showers should move
off to the northeast and out of our area by 00z. The primary short
range issue is the increase in moist air...at low and middle-levels
from the Gulf...and at middle- and upper levels from Pacific Hurricane
Odile. We expect sprinkles tonight as the moist Gulf air (pw over
2 inches) undergoes gentle lift due to terrain. Without a significant
low level source of lift other than a weak sea-breeze...we expect
scattered probability of precipitation and modest quantitative precipitation forecast Tuesday and Tuesday night. Temperatures will
remain slightly below normal with extensive cloudcover and scattered
storms.

Long term (wednesday through monday)...
higher probability of precipitation and quantitative precipitation forecast are forecast for Wednesday and Thursday as
Odile becomes extratropical and is sheared/absorbed by a shortwave
trough moving through the southwestern states. Precipitable water should be at or
above two Standard deviations above normal for September...so when
combined with general lift ahead of the trough axis...will bring
more substantial convection. However...without a source of low-
level lift and focus...we still expect quantitative precipitation forecast to only be in the 1/4
ot 1/2 inch range at many sites for Wednesday through Friday.

The southwestern states trough is slow to move over the weekend...
and may be bolstered by another eastern Pacific tropical cyclone
by Sunday/Monday. We decided to maintain probability of precipitation each day...but less
coverage and with low quantitative precipitation forecast due to a lack of low-level focus.
However...lesser cloudcover and convection should allow
temperatures to rebound to near normal. Longer range models
indicate a cold front passage just beyond this forecast (middle of
next week)...which should lead to continued low to moderate probability of precipitation
and near to slightly below normal temperatures.

&&

Preliminary point temps/pops...
Austin Camp Mabry 72 90 74 91 74 / 10 30 30 30 50
Austin Bergstrom international Airport 69 90 72 90 71 / 10 30 30 30 50
New Braunfels Muni Airport 71 91 73 92 72 / 10 30 30 30 40
Burnet Muni Airport 71 88 72 90 72 / 10 30 30 40 50
del Rio International Airport 72 88 75 89 75 / 10 20 30 30 30
Georgetown Muni Airport 72 88 74 89 73 / 10 30 30 30 50
Hondo Muni Airport 71 91 73 91 72 / 10 30 30 40 30
San Marcos Muni Airport 71 90 73 90 73 / 10 30 30 30 40
La Grange - Fayette regional 73 90 74 90 73 / 10 40 30 30 40
San Antonio International Airport 73 91 76 91 75 / 10 30 30 30 40
Stinson Muni Airport 73 91 75 92 75 / 10 30 30 30 40

&&

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

$$

Mesoscale/aviation...18
synoptic/grids...17
public service/data collection...00

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