Austin / Travis County and South Central Texas Weather Brief
Prepared by Incident Meteorologist Troy Kimmel (www.troykimmelweather.com)
1040am CDT – Friday / 20 September 2013

.. Beneficial Rainfall Event Underway Across South Central Texas …

Stay updated by monitoring the City of Austin low water/flooding website… http://www.atxfloods.com/index.html

At late morning on this Friday.. a southeastward moving cold front combining with an
upper air disturbance.. an increasingly unstable and moist air mass is resulting scattered
to numerous rain showers and thunderstorms. The precipitation is very tropical with
heavy rainfall amounts occurring in relatively short periods of time.

By the time that the precipitation ends tomorrow afternoon, most areas will have
received from 1 to 3 inches of rain with some isolated totals  to near 5 inches.
While the NWS/Austin-San Antonio has issued a flash flood watch for our area,
it’s my thinking that, given the on going severe drought conditions, that the ground
should be able to handle the rainfall.

Current flash flood guidance suggests that.. as a broad guideline.. that it would take
2.6 inches of rain in a one hour period, 3.4 inches in a three hour period and/or 4.4 inches
in a six hour period over Travis County to initiate more widespread flooding
problems. In the Austin metro area, the numbers would, of course,  be a bit lower
due to impervious ground cover. In any case, it should be noted that it is very likely
that some low water crossings are likely to see high water through the rest of the through
tonight and into early Saturday. All flash flood deaths are preventable as long as we use
common sense and remember the NWS slogan.. “turn around, don’t drown.”

I’ll continue to update you on this weather event.

tk