Updated 800am CT – Friday / 29 August 2014
…. Weak Low Pressure Area Moving Westward Through Deep South Texas ….
…. The Chance of Precipitation Over the Next Several Days ….
On this Friday morning…. a weak low pressure area is over deep south Texas. Low pressure and a weak cold front extends south southwestward from western Kansas through west Texas into the southwestern area of Texas. As a result of this surface weather pattern, our local surface winds are south southeasterly.
In the upper levels of the atmosphere… a trough.. or line.. of upper air low pressure extends southward from the central plains into Texas. As a result of this pattern, the upper level winds over south central Texas and the Austin metro area, about 18,000 feet above the ground, are west southwesterly at 10 to 20 mph.
The low pressure area.. over deep south Texas.. is moving westward and this, in combination with daytime heating, increased atmospheric instability as well as the weak front to our west.. will continue the chance of precipitation over south Texas today through tomorrow. As well, the counterclockwise circulation around the low will sweep more moist and unstable air into our area from the southeast. As a result, scattered rain showers and thunderstorms will occur today into tomorrow. Gusty winds and frequent cloud to ground lightning may accompany the thunderstorms. Increased clouds and expected precipitation will result in afternoon high temperatures being a few degrees lower over the next few days.
By tomorrow night into Sunday, upper level high pressure, acting like a “lid” on the atmosphere, will rebuild over the area with rain chances dropping completely from the forecast by Monday through the middle part of next week.
Initial indications are that another low pressure disturbance from the Gulf of Mexico may affect south Texas by the latter part of next week into the following weekend. At this point, I believe that and precipitation that does occur in Texas will be south of our area and I will not include and precipitation chances locally.
Regarding my forecast, my local forecast confidence: My forecast confidence is high through tomorrow (reference precipitation timing and amounts)… then very high tomorrow night through the balance of the seven day forecast period.
Have a good Friday….
Meteorologist Troy Kimmel
Contact me:
tkimmel@austin.utexas.edu
http://www.facebook.com/troykimmel