Text Products for ESF Issued by EWX

Flood Potential Outlook
Issued by NWS Austin/San Antonio, TX
Versions: 1 2 3 4 5 6
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Probabilistic Hydrologic Outlook
National Weather Service Austin/San Antonio TX
1102 AM CDT Thu Mar 21 2024

...Advanced Hydrologic Prediction Service (AHPS) Long Range
Probabilistic Outlook for the Colorado River Basin in South
Central Texas...

The Austin/San Antonio Texas National Weather Service Office
has implemented Advanced Hydrologic Prediction Service
(AHPS) for the Colorado 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 Colorado River at Smithville
has a flood stage of 20 feet. There is a 50 percent chance
the Smithville forecast point will rise above 8.2 feet during
the next 90 days.

         Chance of Exceeding Stages at Specific Locations
                    Valid 03/20/2024 - 06/18/2024


 Location        FS(FT)  90%  80%  70%  60%  50%  40%  30%  20%  10%
 --------        ------  ---  ---  ---  ---  ---  ---  ---  ---  ---
Colorado River
 Austin            33.0 16.6 16.8 17.2 17.7 18.1 18.7 19.1 19.6 20.6
 Bastrop           23.0  5.7  6.3  7.3  8.4 10.7 12.4 14.2 17.4 23.3
 Smithville        20.0  4.1  4.7  5.5  7.1  8.2 10.1 12.2 15.3 22.2
 La Grange         26.0  6.9  8.4  9.0 12.6 13.5 14.3 16.3 19.2 27.6


Llano River
 Llano             10.0  3.0  3.4  3.7  5.4  5.7  6.4  7.0  8.4 11.2


Sandy Creek
 nr Kingsland      12.0  6.6  6.7  6.9  7.2  7.7  8.0  8.6 10.1 11.1


Pedernales River
 Fredericksburg    22.0  5.9  6.2  6.4  6.7  7.4  8.4 10.3 12.0 17.5
 Johnson City      14.0 10.6 10.6 10.6 10.9 11.1 11.5 12.2 13.0 16.8


Barton Creek
 Loop 360 Austin    8.0  2.9  3.0  3.4  3.8  4.5  5.1  5.5  6.6 10.1


Onion Creek
 Hwy 183 Austin    17.0  8.4  9.2  9.8 10.1 10.8 11.5 14.2 17.2 21.0


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 current 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: https://water.weather.gov/ahps2/long_range.php?wfo=ewx

Long-range probabilistic outlooks are issued around the third
Thursday of every month.

$$
National Weather Service Weather Forecast Office
