Updated 130pm CDT Wednesday / 20 June 2012
…. Rain Chances on the Decrease ….
…. Summer Officially Begins at 6:09 pm Austin Time Tonight ….
…. A Drier More Stable Weather Pattern Late Week Through the Weekend ….
…. Afternoon Highs Warming to Well Above Season Averages in the 7 Day Forecast ….
On this Wednesday… a surface high pressure area is over the eastern USA with a trough.. or line.. of surface low pressure extending southwestward from western Kansas into northwest Texas and New Mexico. Another surface high is over the four corners area. A southeastward moving cold front extends from Nebraska southwestward into Colorado and southeastern Utah. As a result of this pressure pattern, a southeasterly surface wind is prevailing across our area.
In the upper levels of the atmosphere, high pressure has continued to settle more to the west of the area over north central and northwestern Mexico. Another upper level high is over the southeastern USA. Between the two system, weak upper air low pressure is over Texas. As a result of the upper air wind flow, the upper level winds are variable over our area.
The upper level low over Texas.. that has produced our rain chances the last few days.. will be dissipating as the two upper air high pressure areas to our west and east begin to merge overhead. As a result, I’ll be decreasing my rain chances tonight into tomorrow with a dry and more stable weather pattern through the remainder of the seven day forecast period as upper level high pressure strengthens overhead and acts like a “lid” on the atmosphere.
It should be noted that with the more stable atmosphere, we will building heat below the upper level “lid” on the atmosphere especially since most folks have not received much rain and the ground remains dry and the drought conditions continue. I will include high temperatures around 100 by the weekend into early next week.
A weak cold front moving southward into north Texas by Friday into Friday should wash out before it gets this far south so little effect from the system is expected. Besides that, the upper level high pressure will suppress upward motion in the atmosphere so no rain chances are indicated.
A quick update regarding the development of a surface low in the Bay of Campache / southwestern Gulf of Mexico for late weekend into next week. The models continue to suggest that any system that does develop will be far enough south, mainly because of the persistent upper level high above us. As a result, no effect expected locally.
A reminder that summer officially begins at 6:09pm tonight as the Summer Solstice occurs.
For Austin and south central Texas… tonight will be mostly cloudy with isolated rain showers and thunderstorms with lows in the 70s. Southeasterly wind. For tomorrow, partly cloudy with isolated to widely scattered rain showers and thunderstorms. Highs in the 90s. Southeasterly wind.
Have a good Wednesday night and Thursday…
Meteorologist Troy Kimmel