Updated 130pm CDT Wednesday / 18 July 2012
…. Very Slim Rain Chances over the Next Day or So ….
…. A Tropical Air Mass Continues Across the Area ….
…. Afternoon Highs Warm over the Next Few Days ….
On this Wednesday… a surface high pressure area is located over the southeastern USA and the lower Mississippi Valley. A weak trough.. or line.. of low pressure extends southward from a low over southeastern Colorado into far southwest Texas. Another surface high pressure area is over western Colorado and New Mexico. As a result of this surface pattern, a light southerly 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 US central plains east southeastward into the Texas and the Mississippi Valley. An area of upper level low pressure area is over far southwest Texas and northeastern Mexico. As a result of the upper air wind flow, the upper level winds are light to moderate southerly over our area.
A moist tropical and unstable air mass continues across the area. However, the upper part of the atmosphere continues to grow a bit more stable over the last 24 hours as the upper low to our west weakens.
As a result, I’m only keeping very slim rain chances the next 24 to 48 hours and then removing the chance of rain from my forecast after that and through the balance of the seven day forecast.
With increased sunshine and the “lid” reestablishing itself in our atmosphere, afternoon high temperatures will be warming back to or just above seasonal averages by the end of the week into the weekend.
For Austin and south central Texas… tonight will see a partly cloudy sky with lows in the 70s. Southerly wind. For tomorrow, partly cloudy with isolated rain showers and thunderstorms with highs in the 90s with a southerly wind.
Have a good Wednesday night and Thursday…
Meteorologist Troy Kimmel