Scientific Forecaster Discussion
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Area forecast discussion
National Weather Service Austin/San Antonio Texas
639 am CDT sun Apr 23 2017
Aviation... /12z tafs/
mostly clear skies should persist through the period although a few
high clouds could stream into western areas by Monday morning.
Breezy conditions should develop mainly from 15-22z with gusts to
around 23 knots possible. Light winds will follow for the remainder
of the taf periods.
Previous discussion... /issued 406 am CDT sun Apr 23 2017/
Short term (today through monday)...
clouds behind the cold front are finally giving way as drier air
begins to move in behind the cold front which moved through the area
yesterday morning. Temperatures are in the 40s and 50s for much of
the area with some 60s still hanging on in the southern counties
where the cloud cover remains.
Today should be picture perfect across the area with clear skies,
lighter winds, and afternoon highs remaining in the 70s across the
area. For tonight, light southerly flow will return to the area as
the surface high shifts to the east of the region. With south flow
back on Monday, high temperatures will respond with afternoon temps
reaching the 80s with even upper 80s expected for the southwestern
counties. Skies will remain mostly clear to partly cloudy with wind
speeds in the 10-15 mph range for the western counties.
Long term (monday night through saturday)...
deep southerly flow will continue into the beginning of the long
term portion of the forecast as a surface low begins to deepen just
north of the Texas Panhandle. At the same time, a strong mid-level
low pressure system in the northern plains will allow the 850 mb
flow over our region to be from the southwest as the wind funnels
into the low to the north. This will cause 850 mb temps to rise to
17-18 c range on Monday and up into the 23-27 c range by
Wednesday morning. This will translate to well above normal
temperatures for most of the long-term portion of the forecast.
Highs Monday will top out in the upper 70s to upper 80s with temps
about 10 degrees warmer on Tuesday.
An upper level trough is progged to move through the Central Plains
Tuesday night which will send the surface low to the east. This will
allow a cold front to move through the County Warning Area Wednesday afternoon. High
temperatures will likely be met before the frontal passage with another day of
90 degree weather for most of the area. Temperatures on Thursday will
be a bit cooler behind the front but likely still above
climatological normals for this time of the year. No rain is expected
with the front as the atmosphere will remain too dry and capped
given the strong southwesterly low-level flow.
The next chance of appreciable rainfall will likely return to the
forecast next weekend as a strong closed low approaches the plains.
Medium range guidance members differ slightly on the timing of the
system but our best chances for rain should be Saturday night as the
frontal boundary moves through the region. This timing could change
slightly over the next several model runs and changes to the forecast
are possible. It is too early to get specific with severe chances as
we will likely be dealing with a capping inversion, but instability
and shear levels would support some severe convection if storms were
able to be sustained and rooted in the boundary layer.
Preliminary point temps/pops...
Austin Camp Mabry 74 50 80 61 90 / 0 0 0 0 0
Austin Bergstrom Intl Airport 73 47 80 60 89 / 0 0 0 0 0
New Braunfels Muni Airport 75 48 80 59 90 / 0 0 0 0 0
Burnet Muni Airport 72 47 78 60 89 / 0 0 0 0 0
del Rio Intl Airport 78 53 85 62 95 / 0 0 - - 0
Georgetown Muni Airport 72 48 79 61 89 / 0 0 0 0 0
Hondo Muni Airport 77 48 83 58 93 / 0 0 0 0 0
San Marcos Muni Airport 74 47 80 60 89 / 0 0 0 0 0
La Grange - Fayette regional 73 48 80 61 87 / 0 0 0 0 0
San Antonio Intl Airport 75 51 81 61 90 / 0 0 0 0 0
Stinson Muni Airport 76 50 80 60 90 / 0 0 0 0 0