Forecast Discussions mentioning any of
"ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 06/10/17
Area Forecast Discussion...UPDATED
National Weather Service Austin/San Antonio TX
908 PM CDT Fri Jun 9 2017
Mesoanalysis reveals CIN quickly developing over the CWA with loss
of daytime heating. As a result storms continue to diminish over the
area, with just two lone cells remaining across southern Blanco and
southwest Hays counties. These may impact portions of Comal county
before dissipating over the next hour or two. Re-adjusted POPs and
hourly T/Td trends for remainder of evening.
.PREV DISCUSSION... /ISSUED 650 PM CDT Fri Jun 9 2017/
AVIATION... /00Z TAFs/
There is an isolated severe threat mainly west of AUS, and a few
showers and thunderstorms have a chance to produce lightning and
gusty winds in the AUS vcnty through around 03Z. Afterwards, a
benign forecast is expected with most of the rapid refresh models
keeping the convection just outside the San Antonio metro area.
Overnight skies should be partly cloudy for the most part but pockets
of mvfr cigs are expected to form over the I-35 terminals toward
daybreak. CIRA SIMWRF fog product has the clouds forming first at
SAT/SSF, so the forecast will continue to show a slight delay before
cigs form over AUS.
PREV DISCUSSION... /ISSUED 305 PM CDT Fri Jun 9 2017/
SHORT TERM (Tonight through Saturday)...
Main forecast concern through the next 6-12 hours will center around
scattered storm chances for portions of the Hill Country and I-35
corridor. Rain chances have been increased during the 5pm to 11pm
time-frame to 40% these areas. A storm or two may become strong with
very localized wind gusts of 30-40 mph and small hail. This risk is
low and coverage is not expected to be large across the region.
Please see below for more details.
Water vapor and RAP analysis depict a positively tilted trough
shifting across NE Texas. The base of the trough will brush across
south-central Texas through the afternoon and early evening and
coincide with maximum instability near 2500 J/Kg. A weak capping
inversion remains in place per aircraft soundings out of KAUS and
KSAT but it should weaken just enough to allow for some isolated to
scattered showers and thunderstorms to develop. Such convective
development has already shown some signals of occurring north of the
region near a small MCV apparent on visible satellite. Hi-res model
trends continue to point towards the development of these showers and
storms across the east Hill Country and northern I-35 corridor. With
DCAPE near 800 J/Kg and weak upper level divergence, a storm may
become strong with small hail and gusty winds. These storms should
not have great overall coverage and remained confined to the I-35
corridor region through the late afternoon and evening. Expect what
storms do develop to weaken by midnight.
Saturday will be a quieter day as the trough actually closes off over
the Texas coast but the region will be on the drier northern flow,
negative vorticity advection area, with slightly lower PWATs. There
could be some limited sea-breeze activity along the Texas coast but
it unlikely to make into the coastal plains and have gone with a dry
forecast with near normal temperatures.
LONG TERM (Sunday through Friday)...
Seasonal pattern of sea-breeze activity will be the main set-up
through late weekend and through much of next week. Coastal plains
will have a 20-30% chance of rain and general thunderstorms each
afternoon with some of this making into the I-35 corridor late into
the afternoons each day. Areas west of I-35 will remain hot and dry
with heat indices reaching into the low 100s.
A weak sub-tropical atlantic H5 ridge and weak H85-H7 inverted
trough along the south Texas coast will aid in moist SE flow through
the week. Daily sea-breeze activity is expected with little to no
expected activity west of I-35. This pattern will persist through
much of next week. Areas will warm into the low to mid 90s each day
with some pockets of upper 90s along the Rio Grande. Heat index
values will increase to 100-105F and precautions should be used
during this heat.
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 70 91 72 92 73 / 20 - - 10 -
Austin Bergstrom Intl Airport 68 90 71 91 72 / 20 - - 10 -
New Braunfels Muni Airport 69 90 70 92 72 / 10 - - 10 -
Burnet Muni Airport 68 89 69 89 70 / 20 - - 10 0
Del Rio Intl Airport 73 96 73 96 73 / - - - 0 0
Georgetown Muni Airport 69 90 71 90 72 / 20 - - 10 -
Hondo Muni Airport 71 93 71 93 72 / 10 - - - 0
San Marcos Muni Airport 69 91 71 91 72 / 20 - - 10 -
La Grange - Fayette Regional 69 90 72 91 73 / 10 - - 20 10
San Antonio Intl Airport 71 91 72 93 73 / 10 - - 10 0
Stinson Muni Airport 71 92 73 93 73 / 10 - - 10 0
Public Service/Data Collection...YB