Updated 845am CT Monday / 20 January 2014
…. Another Cold Front Due This Evening ….
…. A Dry and Stable Progressive Weather Pattern Continues ….
…. A Strong Cold Front with Precipitation Chances Showing Up Late Week ….
On this Monday morning…. a cold front is moving south southeastward through Oklahoma and west Texas. Surface high pressure is over the south and southwestern Gulf of Mexico. As a result of this surface weather pattern, our surface winds are south southwesterly across our area.
In the upper levels of the atmosphere… a counterclockwise rotating upper level low pressure covers eastern Canada and the northern parts of the eastern two thirds of the USA. Upper level high pressure continues the northern and central parts of the west coast Pacific region. A strong upper level low pressure disturbance is noted well west of the Baja Peninsula and southwestern California coast over the Pacific Ocean. As a result of this upper air wind pattern, the upper level winds over south central Texas and the Austin metro area about 18,000 feet above the ground are west northwesterly at 45 to 55 mph.
A dry and stable weather pattern continues over the area. The cold front.. to our northwest.. will move southeastward through our area by this evening. As I’ve noted over the past week or so, with these cold fronts moving through pretty progressively.. or regularly.. it isn’t giving the atmosphere time for low level moisture to return from the Gulf of Mexico. As a result, we’ve seen no precipitation lately and there is no rain in the forecast through mid week.
By Wednesday evening, though, another stronger cold front will arrive about the same time that we see the influence of the subtropical jet stream.. and it’s associated mid and high level moisture.. overrun the colder air. As upper air disturbances move overhead and create atmospheric lift, we’ll see a better chance of light precipitation Thursday into Friday with much colder temperatures.
As the upper level disturbances depart the area, a more stable and warmer weather pattern will develop by next weekend.
Regarding my forecast, my local forecast confidence: My confidence in my forecast is very high through Wednesday.. then falling to medium to high confidence for Wednesday night and Thursday into Friday (some question on precipitation amounts and timing as well as exactly how cold the air mass will ultimately end up being). My forecast confidence rises back to high to very high for Saturday and Sunday.
Have a good Monday…
Meteorologist Troy Kimmel
Contact me:
tkimmel@austin.utexas.edu
http://www.facebook.com/troykimmel