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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
1244 PM CDT Friday may 29 2015

Aviation discussion...for 18z taf package...
should be a fairly quiet day compared to the last few. Still a
chance for isolated storms mostly along the i35 corridor
terminals. Too low confidence to include thunderstorms in the vicinity or tempo groups
however. Therefore VFR should prevail until the overnight period
where IFR ceilings develop at kssf/ksat/kaus. Only MVFR expected at
kdrt. Included prob30 in the 30 hour tafs of kaus/ksat beyond 18z


Previous discussion... /issued 1006 am CDT Friday may 29 2015/

Update...atmospheric conditions have stabilized across south-
central Texas in the wake of the overnight mesoscale convective system. Removed probability of precipitation and
mention of weather for the remainder of the morning hours. Isolated
convective re-development is possible middle to late afternoon.
Updates out.

Previous discussion... /issued 704 am CDT Friday may 29 2015/

have sent an updated set of zones as the Flash Flood Watch has
ended. Models continue to indicate locally heavy rains on Saturday
into Saturday night when a cold front moves across south central
Texas. This may cause a renewed threat of new flooding.

Previous discussion... /issued 647 am CDT Friday may 29 2015/

an area of -ra east of I-35 continues to push off to the east and
will be east of our area by middle morning. Have left vcsh at kaus
for a few hours. Isolated to scattered rain showers/thunderstorms and rain are possible this
afternoon into tonight. Have left mention out of tafs as probs are
too low. Skies start VFR at 29/12z and generally have kept them
that way through this evening. However...a period IFR/MVFR ceilings
is possible middle to late morning and have tempos for this. IFR/MVFR
ceilings develop this evening and continue through the overnight into
Saturday morning when ceilings slowly lift.

Previous discussion... /issued 255 am CDT Friday may 29 2015/

Short term (today through saturday)...
line of showers and storms is finally showing signs of slowly
weakening as it moves southeast with lightning trends steadily
decreasing. Severe winds were the predominant severe type with
several reports of 60 to 70 miles per hour wind gusts across the western and
northern County Warning Area including Bexar County. Rainfall amounts have been
well behaved because the main line of the heavier storms has been
moving at a decent speed around 40-45 miles per hour. Dual-pol precipitation
estimates show widespread 1-2 inches with isolated spots near 3
inches which is about what we were expecting. This line of
showers will continue to push southeast with lingering stratiform
rain expected to persist for several more hours and will let the
Flash Flood Watch continue until the expiration time at 12z. This
residual rain will allow for precipitation amounts to slowly increase for
the rest of the overnight period and this morning. For
today...left higher probability of precipitation in the forecast for the 12z to 18z time
period to account for the stratiform precipitation and will decrease them
in the afternoon hours. Will have 20-30 probability of precipitation in the
afternoon...with the higher probability of precipitation across the eastern counties where
the best moisture will be. Think the atmosphere will be pretty
well worked over and am not expecting too much activity. The ttu
WRF seems to be initialized well and shows very little activity
after 18z.

We will have to watch northwest Texas once again in the afternoon
for thunderstorm development. It should be a bit less than
yesterday due to the absence of significant upper forcing. A large
trough will be passing through the Central Plains and a cold front
is expected to push south into North Texas. This should be the
focus for thunderstorm development and some models are showing
signs these will try to once again congeal into a line...detach
from the front and move south. Most models keep the bulk of the
activity north of our forecast area until Saturday...when the
actual front makes it. Therefore...the chances of a repeat mesoscale convective system
tonight appears to be low. Probability of precipitation will increase Saturday as the slow
moving front moves into the area. With the boundary...there will
always be a chance of locally heavy rain and that will be our main
concern. is tough to Pin-Point exactly where that
will occur and will only continue to mention it in the severe weather potential statement until
more confidence on timing or an area can be obtained.

Long term (saturday night through thursday)...
higher rain chances will continue Saturday night across the
area with the frontal boundary near the area. The threat for
heavy rain should slowly diminish as as upper low is expected to
stall and be nearly stationary well to our east. This stalled
upper low will allow winds throughout the atmospheric column to be
northerly which generally is not the best for heavy rain. Think we
will see diurnally driven convection Monday through
Thursday...mainly in the eastern zones where moisture will be best
and in closer proximity to the upper low. Also...with the north
flow in the atmosphere...precipitable water values will decrease
to below 1.5 inches for most of the County Warning Area on Sunday and last through
the end of the period. This will also help ensure the waning
threat for heavy rainfall. However...we will have to get through
the weekend first.


Preliminary point temps/pops...
Austin Camp Mabry 71 86 67 82 65 / 30 50 50 30 10
Austin Bergstrom international Airport 70 84 66 81 63 / 20 50 50 40 10
New Braunfels Muni Airport 71 85 67 83 65 / 20 50 50 40 20
Burnet Muni Airport 69 82 64 80 63 / 30 60 50 30 10
del Rio International Airport 73 86 68 86 68 / 20 40 50 30 10
Georgetown Muni Airport 70 83 65 81 63 / 30 60 50 30 10
Hondo Muni Airport 72 85 67 84 66 / 20 40 50 40 10
San Marcos Muni Airport 71 84 67 82 65 / 20 50 50 40 10
La Grange - Fayette regional 72 85 67 83 66 / 20 60 50 40 20
San Antonio International Airport 72 86 68 83 67 / 20 50 50 40 10
Stinson Muni Airport 73 86 69 82 67 / 20 50 50 40 10


Ewx watches/warnings/advisories...


public service/data collection...33

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