Updated 845am CST Thursday / 21 November 2013
…. Blue Norther Headed South Through Texas Tomorrow ….
…. Clouds Continues with Rain Chances Ahead of the Cold Front ….
…. Overrunning Clouds / Rain with Much Colder Temperatures Friday into Weekend ….
On this Thursday morning…. a southward moving cold front is over Colorado and Kansas. Surface high pressure is centered over the east northeastern USA. As a result of this surface weather pattern, surface winds are southeasterly over our area.
In the upper levels of the atmosphere… a deepening low pressure trough is over Nevada and California. As a result of the overall upper level wind flow, the upper level winds over south central Texas and the Austin metro area about 18,000 feet above the ground are west southwesterly 20 to 30 mph.
As the warm front, over south Texas, continues to lifts northward, south southeasterly surface winds continue with clouds and rain chances continuing in the forecast. Clouds will continue to thicken and lower across the area through today.
By early tomorrow, the upper air disturbance.. out west.. will continue to strengthen and pass by to our north and reshape the upper air wind pattern to allow for the strong cold front to our north to move rapidly southward through the area. As it moves through the area in the 5am to 8am time period tomorrow, heavier rain showers and thunderstorms are likely with upwards of 1 to 2 inches of rain possible.
As the cold front moves offshore of the Texas coast by late tomorrow, another approaching upper air disturbance will keep moisture overrunning the shallow wedge of much colder surface air with rain chances and clouds persisting through the weekend and even into next week as well. Temperatures be much below average levels by late Friday and through next weekend and into next week. It’s increasing likely that we could see wintry precipitation develop over the northern and western parts of the area.. over the Texas Hill Country.. by Saturday night into Sunday as another upper air disturbance passes.
Latest guidance suggests that another upper air low pressure disturbance will move through the area next Tuesday and this will cause surface development of a low pressure off the Texas coast. As these systems move eastward, clouds will decrease and rain chances will drop from the forecast.
Regarding my forecast, my local forecast confidence: High to very high forecast confidence through tonight.. then a high confidence forecast for tomorrow into tomorrow night. My confidence remains low to moderate for Saturday through the remainder of the weekend into next week (I have some questions regarding whether the air could be colder than anticipated and the extent of winter type precipitation).
Have a good Thursday…
Meteorologist Troy Kimmel