Updated 930am CDT Thursday / 6 September 2012
… Above Average Temps as a Dry Forecast Continues Through Friday …
… Cold Front Due At Sunrise Saturday with a Slim Chance of Rain …
… Windy.. Less Humid and a Little Cooler Saturday into Saturday Night …
On this Thursday… surface high pressure is over the Tennessee Valley with another surface high over southern Colorado and the four corners area. A trough. or line.. of low pressure extends southward from a surface low over northern Oklahoma southwestward into far southwest Texas. As a result of this surface pattern, a southerly surface wind is prevailing across our area.
In the upper levels of the atmosphere, a upper high pressure ridge, acting like a lid on the atmosphere, is situated from Texas westward into the southwestern USA. An area of upper air low pressure is over the southeastern USA.. Florida and the adjacent eastern Gulf of Mexico. As a result of the upper air wind flow, the upper level winds are generally light and variable over our area.
A dry and stable summertime weather pattern continues across our area.
The upper air pattern is still slated to change across the USA by the weekend as a trough.. or line.. of upper air low pressure over the eastern half of the country and our winds aloft over our area turn northwesterly and increase. This will support a surface cold front to sweep southeastward through our area of Texas early Saturday morning. The situation.. due to time of day and the expected atmospheric moisture profile.. will be less favorable for precipitation. Isolated to widely scattered rain showers and thunderstorms will develop just ahead of.. along and just behind the front. It appears that rainfall of 1/4 inch or less will occur with these thunderstorms locally.
Skies will clear with gusty northerly wind.. lower humidity and slightly cooler temperatures for Saturday into Saturday night. Winds will decrease by Sunday but the cooler and drier continuing Monday as the surface high pressure behind the front builds into the area from the north northwest.
Please note that the gusty northerly wind following the cold front early Saturday.. combined with the dry vegetation and low humidity… will create high wildfire danger for Saturday into Saturday night.
For Austin and south central Texas… tonight will see a mostly clear sky with low clouds late with lows in the 70s with a southerly wind 8 to 15 mph. For tomorrow, some morning low clouds will give way to a mostly sunny with highs around 104 with a southerly wind 8 to 15 mph.
Have a good Thursday night and Friday…
Meteorologist Troy Kimmel