000
FGUS74 KEWX 191748
ESFEWX
TXC019-029-187-255-325-493-201148-
PROBABILISTIC HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1248 PM CDT THU JUL 19 2012

...ADVANCED HYDROLOGIC PREDICTION SERVICE (AHPS) LONG RANGE
PROBABILISTIC OUTLOOK FOR THE SAN ANTONIO RIVER BASIN IN SOUTH
CENTRAL TEXAS...

THE AUSTIN/SAN ANTONIO TEXAS NATIONAL WEATHER SERVICE OFFICE 
HAS IMPLEMENTED ADVANCED HYDROLOGIC PREDICTION SERVICE
(AHPS) FOR THE SAN ANTONIO RIVER BASIN IN SOUTH CENTRAL TEXAS.
AHPS ENABLES THE NATIONAL WEATHER SERVICE TO PROVIDE LONG-RANGE 
PROBABILISTIC OUTLOOKS.  THIS SERVICE IS ALSO AVAILABLE ON THE
INTERNET.

IN THE TABLE BELOW...THE 90 THROUGH 10 PERCENT COLUMNS INDICATE 
THE CHANCE THE RIVER COULD RISE ABOVE THE LISTED STAGE LEVELS 
IN THE NEXT 90 DAYS.  EXAMPLE:  THE SAN ANTONIO RIVER AT ELMENDORF
HAS A FLOOD STAGE OF 35 FEET.  THERE IS A 50 PERCENT CHANCE  
CHANCE THE ELMENDORF FORECAST POINT WILL RISE ABOVE
18.7 FEET
DURING THE NEXT 90 DAYS.


         CHANCE OF EXCEEDING STAGES AT SPECIFIC LOCATIONS
                    VALID 7/18/2012 - 10/17/2012


 LOCATION        FS(FT)  90%  80%  70%  60%  50%  40%  30%  20%  10%
 --------        ------  ---  ---  ---  ---  ---  ---  ---  ---  ---
MEDINA RIVER
 BANDERA         13.0    5.0  5.3  5.6  6.0  6.3  7.7  9.4 12.0 14.4
 LA COSTE        15.0    5.4  5.4  5.4  5.4  5.4  5.4  5.4  5.4  5.4
 SOMERSET        18.0    4.3  4.4  4.7  5.0  5.3  5.6  6.5  7.7 10.1
 US281           20.0    3.4  3.7  4.0  4.5  5.3  6.1  8.0  9.4 14.1


SALADO CREEK
 LOOP 13         18.0    7.2  7.8  8.6  8.9  9.3  9.9 10.4 11.8 13.9


SAN ANTONIO RIVER
 ELMENDORF       35.0   12.1 13.4 14.8 16.4 18.7 22.4 25.7 30.2 35.4
 FALLS CITY      12.0    3.6  3.6  3.6  3.6  3.6  3.9  5.0  6.0  8.6


CIBOLO CREEK
 SELMA           17.0    2.7  2.7  2.7  2.7  2.9  3.9  4.5  4.9  5.7
 NR FALLS CITY   17.0    2.4  2.4  2.4  2.5  3.6  4.8  5.9  7.7 12.8


THIS LONG-RANGE PROBABILISTIC OUTLOOK CONTAINS NUMBERS THAT ARE
CALCULATED USING MULTIPLE SCENARIOS FROM 50 YEARS OF HISTORICAL
CLIMATOLOGICAL AND STREAM FLOW DATA.  THESE NUMBERS ALSO TAKE 
INTO ACCOUNT CURRENT CONDITIONS OF THE RIVER AND SOIL MOISTURE.
BY PROVIDING THE COMPLETE RANGE OF PROBABILISTIC NUMBERS...THE
LEVEL OF RISK ASSOCIATED WITH THE LONG-RANGE PLANNING DECISIONS
CAN BE DETERMINED.


ADDITIONAL SUPPORTIVE DATA AND EXPLANATION ARE AVAILABLE ON THE
INTERNET AT:  WWW.SRH.WEATHER.GOV/CGI-BIN/AHPS.CGI?EWX
(INTERNET ADDRESS IS ALL LOWER CASE).


LONG-RANGE PROBABILISTIC OUTLOOKS ARE ISSUED AROUND THE THIRD 
THURSDAY OF EVERY MONTH.


$$