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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
650 PM CDT Tuesday Jul 7 2015

Aviation...
a band of rain showers from just west of kpez to kcvb to k5c1 to kbmq to
Kile will drift further to the northwest and then dissipate later
this evening. Have mentioned vcsh at ksat as rain showers are in vicinity to
this Airport...though they will move away from it and dissipate in
a couple of hours. A line of rain showers/thunderstorms and rain from k6r6 to ksoa will
slowly move to the south. Currently expect it will remain north of
kdrt while slowly dissipating this evening. However...will monitor
radar trends and update to mention there if needed. Skies will
start out VFR. Stratus with MVFR ceilings will develop later this
evening and persist into the middle morning hours. Some spots may see
brief IFR ceilings. The stratus will mix out late morning to midday
with skies becoming VFR. A repeat of the stratus is expected
Wednesday night. S to southeast winds 8 to 14 kts tonight will increase to
14 to 18 kts with some gusts up to 30 kts on Wednesday. Wind gusts
up to 35 kts are possible with the Edwards Plateau thunderstorms and rain. Some low level wind shear
is possible overnight.

&&

Previous discussion... /issued 501 PM CDT Tuesday Jul 7 2015/

Evening update...
watching a cluster of storms north of Val Verde and Edwards County
continue to push southeastward this afternoon. Short term models
continue to want to dissipate this activity as they move towards
the County Warning Area but latest radar and satellite trends do not agree.
Continue to cloud tops below -75 degrees as of the 22z and plenty
of lightning activity in the updrafts of these cells to anticipate
their longevity enough to enter our northwestern zones. As
such...raised probability of precipitation to likely in Val Verde and Edwards counties for
tonight and increased probability of precipitation a bit farther eastward. Do think the
downtrend will begin in the next hour or so as we should lose
convective potential with the loss of sunlight. Also...700 mb
moisture decreases farther southwest...so entrainment of drier air
should begin to take place as well.

Hourly temperatures were about 10 degrees too warm out west as
well so repopulated observation and blended into rap trends as these had
the closest handle on whats going on.

Previous discussion... /issued 302 PM CDT Tuesday Jul 7 2015/

Short term (tonight through Wednesday night)...
the latest radar data shows convection over Chihuahua Mexico has
weakened while slowly moving east toward the Rio Grande. Looking
farther to the west and northwest across The Big Bend and lower
trans Pecos...some clearing is underway. Radar data is beginning to
show an uptick in activity as daytime heating helps to destabilize
the lower levels. Elsewhere...some isolated showers and
thunderstorms are ongoing mainly along and east of the Highway 77
corridor. The activity out west along the Rio Grande plains and
southern Edwards Plateau is expected to continue tonight given a
moist axis across west and northwest Texas. We/ll continue to
forecast a good chance for precipitation across the mentioned region
through tonight. The activity farther east will be tied closely to
daytime heating and will not mention a chance for precipitation
beyond 7 PM. On Wednesday...we/ll maintain a slight chance for
convection across western Val Verde and extreme northwestern Edwards
counties...with most activity expected during the daytime hours. As
far as temperatures are concerned...daytime highs will be slightly
below normal...while overnight lows will be a few degrees above
normal.

Long term (thursday through tuesday)...
the long term portion of the forecast will be dominated by
strengthening subtropical high pressure in the middle and upper levels
of the atmosphere. This will bring a warming trend to south central
Texas through the upcoming weekend into early next week. We/ll also
go with a dry forecast for all areas on Thursday as precipitable
water values drop. The decrease in moisture should also result in
less cloud cover during the late night and early morning hours. On
Friday and Saturday...we expect enough moisture to return for
isolated afternoon and evening convection near the coastal plains.
The center of the subtropical ridge axis shifts into northern New
Mexico/southern Colorado early next week as a weak cold front slips
into Oklahoma. At this time...this front is not expected to impact
our region through the current forecast period. For now...we/ll call
for near normal temperatures with dry weather into early next week.

&&

Preliminary point temps/pops...
Austin Camp Mabry 76 92 75 93 73 / 10 - - 0 0
Austin Bergstrom international Airport 76 92 75 92 73 / 10 - - 0 0
New Braunfels Muni Airport 74 92 74 91 73 / 10 - - 0 -
Burnet Muni Airport 74 90 73 91 71 / 20 - 0 0 0
del Rio International Airport 77 94 76 94 75 / 30 10 0 0 0
Georgetown Muni Airport 76 92 75 91 72 / 10 - 0 0 0
Hondo Muni Airport 75 92 74 92 73 / 10 - 0 0 0
San Marcos Muni Airport 75 92 75 91 72 / 10 - - 0 -
La Grange - Fayette regional 77 92 75 91 74 / 10 - 0 - 0
San Antonio International Airport 75 92 75 92 73 / 10 - 0 0 0
Stinson Muni Airport 74 93 75 91 74 / 10 - 0 0 0

&&

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

$$

Mesoscale/aviation...04
synoptic/grids...tb3
public service/data collection...Treadway

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