Area Forecast Discussion
Issued by NWS Austin/San Antonio, TX
FXUS64 KEWX 271152 AAA
Area Forecast Discussion...UPDATED
National Weather Service Austin/San Antonio TX
652 AM CDT FRI MAY 27 2016
.AVIATION.../12Z TAF CYCLE/
SHRA and TSRA have moved to the east of KAUS as of 1145Z but some
remaining activity is ongoing 30-50 miles north that could cause
aviation concerns on departure north or approach to the south.
KSAT/KSSF are clear of weather concerns but have MVFR conditions
along with KAUS. KDRT is clear of clouds at this time and should
remain VFR through the day.
KSAT/KSSF/KAUS will slowly improve to VFR through the late morning
to early afternoon while remaining mostly free of weather
concerns. Additional TSRA/SHRA is expected to develop by mid
afternoon near KAUS and have placed VCTS accordingly. Weather
concerns should dissipate through the late evening and overnight
Saturday but another round of SHRA.TSRA could occur again
Saturday. Surface winds will remain east to southeast through the
period at central TAF sites with KDRT more westerly as the dryline
moves through late today.
.PREV DISCUSSION... /ISSUED 453 AM CDT FRI MAY 27 2016/
SHORT TERM (Today through Saturday)...
The main focus for the next several hours will be monitoring any
lingering precipitation early this morning. Currently we have one
area of moderate to heavy rainfall that has just moved east of
Fayette county. Radar data also shows some activity farther north
moving into central Texas. Trends continue to suggest this
activity will remain east and north of our region early this
morning. Although we can`t rule out additional showers and
thunderstorms this morning, it appears only light to moderate
rainfall is expected. Earlier activity has dropped some very
impressive rainfall totals with several gauge reports of 8 to near
11 inches across Bastrop, Lee and northern Fayette counties. Radar
estimated totals also show nearly 12.5 inches of rain has fallen
to the northeast of Giddings.
As we head into the afternoon hours, the models suggest the
dryline will be able to mix eastward close to the U.S. Highway 281
corridor by midday. Meanwhile, an active southwest flow aloft will
continue across Texas. With the active flow aloft, plenty of
moisture and daytime heating, we could see another round of
showers and thunderstorms develop this afternoon. Given the very
heavy rainfall that occurred late Thursday into early today, we
have opted to keep the Flash Flood Watch for counties along and
east of a Burnet to San Marcos to Gonzales to Cuero line. Farther
west, the flood threat has been reduced, so the watch has been
cancelled. In addition to the heavy rain concerns, we could see
some strong to severe thunderstorm development generally along and
east of Highway 281. However, it appears the stronger lift and
ingredients for severe weather will remain over north Texas today.
On Saturday, an active southwest flow aloft remains in place. The
models are showing an increase in mid-level shortwave activity
across far west Texas. This should provide a better chance for
storms to the southern Edwards Plateau and Rio Grande plains on
LONG TERM (Saturday Night through Thursday)...
As we head into the latter portion of the weekend into early next
week, we`ll continue to see a fairly active weather pattern across
the region. Rain chances will be favored across the southern
Edwards Plateau and western Hill Country as this area should
remain in proximity to the stronger upper level lift. It will be
difficult to time exactly when the stronger upper level support
will move across south central Texas. At this time, we will
generally keep rain chances in the 20-40% range Saturday night
through Tuesday night. An uptick in precipitation chances is
currently forecast for the middle of the upcoming work week. If
the ECMWF mos guidance remains consistent, we will need to
increase our rain chance for the middle and latter portion of the
upcoming work week.
With the recent rainfall, some significant rises have been
observed or are expected to occur on area rivers. Most notably is
the current forecast calling for major flooding of the Colorado
River at Bastrop, Smithville and La Grange. In addition, moderate
flooding is expected on Onion Creek at Highway 183.
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 87 73 89 72 86 / 60 30 30 20 20
Austin Bergstrom Intl Airport 87 73 89 72 86 / 60 30 30 20 20
New Braunfels Muni Airport 89 73 89 72 86 / 50 30 30 20 20
Burnet Muni Airport 87 71 89 70 84 / 60 20 30 30 20
Del Rio Intl Airport 96 70 91 73 88 / 10 10 40 30 30
Georgetown Muni Airport 86 72 89 71 85 / 60 30 30 20 20
Hondo Muni Airport 93 72 90 73 86 / 30 20 30 30 20
San Marcos Muni Airport 87 73 88 71 85 / 60 30 30 20 20
La Grange - Fayette Regional 86 74 88 73 87 / 70 40 30 10 20
San Antonio Intl Airport 89 74 89 73 86 / 40 20 30 20 20
Stinson Muni Airport 92 75 90 74 87 / 40 20 30 20 20
Flash Flood Watch until 6 PM CDT this evening for the following
counties: Bastrop...Burnet...Caldwell...De Witt...Fayette...