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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
646 am CDT Tuesday Sep 16 2014

Aviation...
isolated rain showers will become scattered rain showers/isolated thunderstorms and rain this afternoon and
continue through Wednesday morning. At the taf sites...have tempos
for this afternoon into evening between 16/18z-17/04z and vcsh
overnight after 17/06z and then prevailing rain showers Wednesday
morning after 17/12z. VFR skies prevail today into this evening.
Except brief MVFR ceilings early this morning and with isolated to scattered
rain showers. Increasing moisture will lead to MVFR ceilings overnight into
Wednesday. Ely winds 10 kts will prevail...except some gusts up to
30 kts in and near shra/tsra.

&&

Previous discussion... /issued 339 am CDT Tuesday Sep 16 2014/

Short term (today through wednesday)...
current weather map is showing an upper trough moving through the
northeast U.S. And an upper ridge axis from the Great Basin up
through western Canada. In addition Tropical Storm Odile over the
Baja California peninsula is sending a ton of moisture into the desert SW and
much of Texas. Current radar is showing some light echoes moving
from west to east across central Texas...moving along the westerly
middle level winds. Will keep chance pop up through this morning over
the northern zones although precipitation will remain very light. Plenty
of low/mid/high clouds will keep the area mostly cloudy/cloudy
over the next several days.

This influx of moisture not only from Odile but also from a surface
trough off the Texas coast...will increase pop over much of the County Warning Area
for the next 72 hours at least. Already coastal areas are seeing
predawn tropical showers moving and forming inland. Highest pop
today (60 percent) will be along the southeast coastal
counties...lower chance pop over the far west. There is not a
strong upper or low level trigger...so mainly daytime heating and
boundary driven convection is expected. Should see a decrease in
sh/ts activity by late evening but given the high precipitable water values will
have to carry at least some pop overnight. Heavy downpours with
high rain rates are possible..not only today..but for the next
several days.

Long term (wednesday night through monday)...
forecast precipitable water values will peak over the next 36-48 hours...well
over 2 inches. Chance pop will continue through at least Thursday
for most areas...highest chances in the south and
southeast...lesser chances as you head to the far west near and
along the Rio Grande. Slow moving storms could pose some isolated
and minor flooding concerns through middle week. Newest European model (ecmwf)
guidance is painting likely pop even toward the end of the week as
precipitable water remains high. Wont go that high just yet but something to
watch. Another thing to watch is a cold front moving through our
part of the state on Sunday. Am carrying slight pop right
now...but weekend pop may have to be increased if tropical
moisture is still present by the time front arrives.

&&

Preliminary point temps/pops...
Austin Camp Mabry 88 74 88 74 87 / 40 20 40 30 50
Austin Bergstrom international Airport 88 72 89 72 87 / 40 20 40 30 50
New Braunfels Muni Airport 89 73 89 73 88 / 40 20 40 30 50
Burnet Muni Airport 87 73 87 72 87 / 30 20 40 30 50
del Rio International Airport 88 75 88 74 89 / 20 20 40 20 20
Georgetown Muni Airport 88 74 87 73 86 / 30 20 40 30 50
Hondo Muni Airport 91 73 91 73 91 / 40 20 40 20 40
San Marcos Muni Airport 88 73 88 73 87 / 40 20 40 30 50
La Grange - Fayette regional 89 74 87 73 86 / 50 30 50 30 50
San Antonio International Airport 89 76 90 76 89 / 40 20 40 30 50
Stinson Muni Airport 89 75 91 75 91 / 40 30 40 30 50

&&

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

$$

Mesoscale/aviation...04
synoptic/grids...09

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