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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
316 am CST Thursday Jan 29 2015

Short term (today through friday)...
patchy dense fog this morning will persist through the middle morning
before mixing out. A cold front will push through the County Warning Area during
the early afternoon and halt temperatures in the low to middle 70s in
the northern County Warning Area and upper 70s in the south. Winds will shift to
the northeast and eventually north by this evening with 10-20 miles per hour
behind the front.

Meanwhile...an 500 mb trough begins its trek onshore from Baja California
California which will result in broad downstream upper level
support spanning from eastern New Mexico across much of Texas. The
trough will phase Pacific moisture with Gulf return flow beginning
late Friday and precipitation development will begin and spread into West
Texas. Think Friday itself will be dry for the majority of the day
with only the Rio Grande Valley with 20 probability of precipitation in the afternoon.
Believe the appreciable precipitation will begin after 00z Saturday.

&&

Long term (friday night through wednesday)...
beginning 00z Saturday...the broad 500 mb forcing characterized by 50
knots flow will coincide with a developing 850 mb low level jet over southern
and central Texas. The weak upper level divergence associated with
the low...deep but meager Omega generation...but the strong low level jet
should result in a steady rain period beginning late Friday night
through Sunday. Confidence remains high on the Prospect of rain
during this time period...but it doesnt look like rain rates will
be too impressive with such broad forcing. Wpc estimates are only
calling for a 48 hour total of one half to one inch of total
rainfall across the County Warning Area. This looks reasonable. Also removed the
thunder mention as lapse rates arent quite as conducive as
yesterdays model runs. All in all...the event should be pretty
hazard free.

A brief dry period will set up Monday and Tuesday as the low drops
farther south as far as the Gulf of California. The overall Continental U.S.
Pattern of a trough over the eastern Seaboard will separate the
Pacific low and cut off upper level support for Texas for a short
while. As the low then begins an eastward motion through the
southern tip of Texas and across the Gulf Coast...it will then
interact with rich Gulf moisture Wednesday and result in low end
pop chances for areas in close proximity to the Gulf Coast. Thus
left 20-30 pop chances in the east for this period. The bulk of
the precipitation that the low will generate before finally shifting east
of the state will likely be more of an impact for crp/hgx.

Tb3

&&

Preliminary point temps/pops...
Austin Camp Mabry 73 45 59 45 57 / - 10 10 30 70
Austin Bergstrom international Airport 74 44 58 43 57 / - 10 10 30 70
New Braunfels Muni Airport 74 46 58 45 59 / - 10 10 30 70
Burnet Muni Airport 71 42 56 42 52 / - 10 10 30 80
del Rio International Airport 74 50 58 47 59 / - 10 20 60 80
Georgetown Muni Airport 72 43 57 43 54 / - 10 10 30 70
Hondo Muni Airport 74 47 60 46 60 / - 10 10 50 70
San Marcos Muni Airport 73 45 58 45 58 / - 10 10 30 70
La Grange - Fayette regional 74 47 59 46 61 / - 10 10 20 60
San Antonio International Airport 74 47 58 47 59 / - 10 10 30 70
Stinson Muni Airport 74 48 59 47 61 / - 10 10 30 70

&&

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

$$

Mesoscale/aviation...04
synoptic/grids...03

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