Updated  945am Tuesday / 21 February 2012

…. A Quiet Week Ahead Weather Wise for Austin and South Central Texas ….
…. Series of Dry Cold Fronts Through the Area over the Next Three or Four Days ….
…. Above Average Temps First Half of Week; Turning Cooler Late Week ….

On this Tuesday… a low pressure area over the middle Mississippi Valley has a cold front extending southward into central Mississippi and southern Louisiana to the Texas coastal plains. A weak surface high pressure area is over east Texas. As a result of this surface pressure pattern, a south southeasterly surface wind has returned across our area.

In the upper levels of the atmosphere… a broad trough.. or line.. of upper air low pressure is located over the central and western parts of the USA. Within this counterclockwise rotation, a low pressure disturbance is centered over the middle Mississippi Valley with a secondary upper air low pressure disturbance over the northern parts of the Baja Peninsula. As a result of this pressure pattern, the upper air winds are moderate westerly across Texas and our local area.

Given the progressive (fast moving) of our current weather pattern, the surface high pressure area, that settled south following the front in the predawn hours this morning, will move eastward quickly with south southeasterly wind already returning to the area.

Southerly surface wind flow will continue through tomorrow and tomorrow night and into Thursday before a stronger cold front moves through the area during the afternoon and evening hours Thursday. Moisture return and instability in advance of this front still looks a bit limited, again, due to the progressive nature of our weather pattern. I’ll include a slim chance of rain showers and thunderstorms in the forecast as the front passes.

Cooler.. drier and more stable air will build into the area Thursday night into Friday as surface high pressure from the Rockies and the plains states moves our way.

As the surface high moves eastward, surface winds will return southerly by late Saturday into Sunday and Monday with clouds on the increase once again.

My forecast confidence through this week is high to very high with the timing of the cold front late Thursday and any associated rain chances being the main questions. My confidence for the forecast for late week through next weekend is high to very high.

For Austin and south central Texas… tonight will be partly cloudy with low clouds developing late. Lows in the 50s with a southerly wind. For tomorrow, morning low clouds and patchy fog will give way to a partly cloudy sky. Highs in the 70s with a south southwesterly wind.

Have a good Tuesday night and Wednesday…
Meteorologist Troy Kimmel