Updated 800am CT – Friday / 10 October 2014
…. A More Unsettled Air Mass through the Weekend As a Weak Cold Front Moves In ….
…. A Stronger Cold Front Sweeps Across Texas Early Monday with Thunderstorms ….
On this Friday morning…. a surface low pressure area is over western Oklahoma with a trough.. or line.. extending southwestward through west Texas and eastern New Mexico with a cold front extending from the low over Oklahoma across the Texas south plains into New Mexico and Colorado. As a result of this surface weather pattern, our local surface winds are southerly.
In the upper levels of the atmosphere… a eastward moving upper air low pressure disturbance is over southern Colorado and northern New Mexico. Upper level high pressure.. acting like a lid on the atmosphere.. extends from northeastern Mexico across deep south Texas and the northwestern Gulf of Mexico. 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 southwesterly less than 20 mph.
Low level moisture has increased across our area of Texas and the atmosphere has become a bit more unstable.
Remnant mid and upper air moisture from the Pacific Ocean will combine with available atmospheric instability.. low level gulf moisture as well as the approaching upper level low pressure disturbance to give us increased rain shower and thunderstorm chances by tonight into tomorrow. Current indications are that we would see widely scattered to scattered precipitation. With the upper air disturbance approaching, a surface cold front will move down into the area by Saturday with it washing out just to our south by tomorrow night into early Sunday and returning back northward as a warm front during the day Sunday.
By late Sunday night into Monday morning, as the main part of the upper air disturbance moves across Texas, a strong cold front will surge southeastward through Texas with perhaps the best rain shower and thunderstorm chances of the seven day forecast. Guidance suggests that the cold front will arrive in our local area sometime between 5am and 9am Monday. Drier.. much drier and slightly cooler air will overtake the state of Texas.
The latest rainfall guidance from the NWS suggests that we will see upwards to 1/2 to 1 inch of rain between now and Tuesday.
Regarding my forecast, my local forecast confidence: My forecast confidence is medium to high through the weekend in regards to precipitation occurrence and timing, precipitation amounts as well as the timing of the cold front early next week. My forecast guidance goes back to high to very high by midday Monday through the middle part of next week.
Have a good Friday….
Meteorologist Troy Kimmel
Contact me:
tkimmel@austin.utexas.edu
http://www.facebook.com/troykimmel