Updated 130pm CDT Wednesday / 11 July 2012

…. An Unstable Air Mass Continues to Yield Better Rain Chances Through Tonight …
…. Rain Chances Slowly Decreasing late Week into the Weekend ….
…. With Increased Sun, Warmer Temps Due late Week into the Weekend ….

On this Wednesday… a surface high pressure area is located over the southeastern USA  and the northeastern Gulf of Mexico. A weakening stationary front extends southwestward from western Tennessee southwestward to northern Louisiana and over south central Texas. Texas. Another surface high pressure area is north of the weakening front over the Texas panhandle. As a result of this surface pattern, a fairly  variable surface wind is prevailing across our area.

In the upper levels of the atmosphere, the upper high pressure ridge, acting like a lid on the atmosphere, continues broadly over the southwestern USA with a broad upper level low pressure area from the lower Mississippi Valley west southwestward into Texas. As a result of the upper air wind flow, the upper level winds are light north northeasterly over our area.

A moist tropical and unstable air mass continues across the area. I will continue the good rain chances through tonight as the weak cold front washes out overhead. This front.. combined with available moisture and atmospheric instability.. continues to increase the atmospheric lift in the moist tropical unstable air mass and result in higher than climatologically average rainfall chances for this time of year. I still think that some areas may see another inch or two of rain before the rain chances taper off tomorrow into Friday. Given what we’ve seen the last few days, isolated heavier amounts, of course, are possible given the tropical moisture available.

Partial clearing.. with slowly lower rain chances and warmer temperatures are expected late week through the weekend and into early next week.

For Austin and south central Texas… tonight will see a cloudy sky with scattered to numerous rain showers and thunderstorms with lows in the 70s. Southerly wind. For tomorrow, partly cloudy with scattered rain showers and thunderstorms with highs around 90. Southerly wind.

Have a good Wednesday night and Thursday…
Meteorologist Troy Kimmel

Contact me:
tkimmel@mail.utexas.edu
http://www.facebook.com/troykimmel