Updated 915am CT – Tuesday / 07 July 2015
.. Watching Thunderstorms to our Distant West Northwest ..
.. A Mostly Dry and Stable Weather Pattern Continues Locally ..
On this Tuesday…. a weakening southeastward moving cold front extends from southwestern Missouri into central Oklahoma into s surface low pressure area near Abilene, TX. From there, a weak cold front extends west southwestward into southwest and far west Texas and northwestward into southwestern New Mexico. Surface high pressure is over the eastern half of the Gulf of Mexico and southeastern USA. As a result of this surface weather pattern, our local surface winds are southerly.
In the upper levels of the atmosphere.. an upper level high pressure area, acting like a “lid” on the atmosphere, has settled southward and extends eastward from northern Mexico across south Texas and the northwestern Gulf of Mexico. A convectively induced upper air low pressure disturbance is located over northwest Texas near Childress. As a result, our upper air winds at about 18,500 feet, are light westerly.
A summer weather pattern.. for the most part.. continues with a moist and tropical air mass holding across the area.
However, there are a few complicating factors that have cropped up in the last 12 hours that make me a bit more uncertain about rainfall probabilities particularly for tonight into Wednesday. A southward moving surface cold front.. producing atmospheric lift.. is weakening over southwest and northwest Texas. A widespread area of overnight thunderstorms over west Texas.. which has produced nearly 6 inches of rain in Abilene since 3am this morning.. has resulted in a convectively (thunderstorm) induced upper air disturbance over northwest Texas. All of these features add instability to the atmosphere and an increased chance of additional thunderstorm development in areas to our northwest over the next 12 to 24 hours. The latest high resolution short term precipitation models suggest rain showers and thunderstorms moving as far southeast as Burnet county.. just to our northwest.. by 10pm to 12 midnight tonight.
At this point, however, I’m holding off rain chances as I think the probability of precipitation for any given place along the IH35 corridor is still 10% or less. I’ll continue to monitor in case changes are needed in the forecast.
One we get past tomorrow.. it looks like a rather typical and benign summer weather pattern prevailing through the balance of the week with afternoon high temperatures near seasonal averages.
Have a good Tuesday….
Meteorologist Troy Kimmel
Contact me:
tkimmel@austin.utexas.edu
http://www.facebook.com/troykimmel