Updated 800am CT – Tuesday / 23 December 2014
…. Cooler with Some Rain with a Passing Upper Air Disturbance Today ….
…. A Drier Weather Pattern with Sunshine Wednesday into Late Week and the Weekend ….
…. Another Late Week Cold Front ….
On this Tuesday morning…. a southeastward moving cold front extends from a surface low pressure area over eastern Iowa and northwestern Illinois southward into west Tennessee and central Louisiana to onshore of the Texas coast and then into northern Mexico. High pressure is located behind the front over the Pacific northwest. As a result of this surface weather pattern, our local surface winds are northerly.
In the upper levels of the atmosphere.. a deep area of upper level trough.. or line.. of low pressure is centered over the central and northern plains extending south southwestward into Texas and northern Mexico. As a result, our upper air winds at about 18,500 feet are west southwesterly 65 to 75 mph.
As the upper level low pressure area overhead moves further eastward and our winds aloft become more northwesterly, the cold front, now along the Texas coast, will sweep southeastward well into the Gulf of Mexico. Clouds and some overrunning rain will continue over our area until the upper air disturbance departs off to the northeast by later this afternoon into tonight.
As surface high pressure builds into the area and the upper level low pressure area departs the area to the east, a dry and stable early winter weather pattern will return with abundant sunshine tomorrow with plenty of sunshine and a little of a warm up by Christmas Day.
Another cold front.. dry in nature.. will sweep southeastward through the area by midday Friday.
Surface high pressure will build into the area in the wake of the front.
The latest guidance now suggests another passing upper air disturbance with increased clouds and slim overrunning rain chances for Saturday into Saturday night. Once that disturbance passes, we’ll return back to more sunshine Sunday into the first part of next week. Temperatures will be below average for the extended forecast period.
Regarding my forecast, my local forecast confidence: My forecast confidence is high to very high through Friday and Friday night with my confidence falling back to medium for Saturday and Saturday night (rain chances, timing and amounts being the issues). Beyond that for Sunday into early next week, my forecast guidance is back to high.
I will be taking off Thursday / 25 December through Thursday / 1 January 2015.. and will return to updating my website on Friday / 2 January 2015. I will be posting a link to the latest NWS forecast for Austin and south central Texas during my absence.
Have a good Tuesday….
Meteorologist Troy Kimmel
Contact me:
tkimmel@austin.utexas.edu
http://www.facebook.com/troykimmel