Updated 845am CT Thursday / 9 January 2014
…. Clouds Persist ….
…. Passing Upper Air Disturbance with a Better Chance of Rain into Tomorrow ….
…. A Drier and More Stable Weather Pattern for the Weekend into Next Week ….
On this Thursday morning…. a massive surface high pressure area is over the eastern Great Lakes states and the mid Atlantic coastal region of the USA. A weak surface low pressure area is over Texas in association with a weak cold front over north central Texas extending southwestward over southwest Texas. As a result of this surface weather pattern, surface winds are light south southeasterly across our area.
In the upper levels of the atmosphere… a broad counterclockwise rotating upper level low pressure trough is over the USA with embedded disturbances.. acting like spokes on a bicycle wheel.. over the northwestern USA.. over the northeastern USA.. and a couple located over the southwestern USA. As a result, the upper level winds over south central Texas and the Austin metro area about 18,000 feet above the ground are generally westerly at 35 to 45 mph.
A south southeasterly surface wind flow has persisted over our area over the last few days as the bitterly cold Arctic air mass.. in place earlier in the week.. moves off to the northeast. Weak low pressure disturbances have produced a few light rain showers over the past 24 hours.
By later tonight into Friday.. the two upper air low pressure disturbances to our west will move eastward and increase atmospheric instability and lift with a better chance of rain showers and even a few thunderstorms.. particularly tomorrow afternoon. As the disturbances move eastward overhead by late tomorrow and then off to our east and northeast, the weak cold front to our northwest will move through the area allowing dry and more stable air.. with a return to sunshine.. to return for the weekend.
Forecast guidance strongly suggests that another dry cold frontal passage by Sunday night with simply a reinforcement of drier and more stable air for the first half of next week. Temperatures are expected to be near seasonal averages for the first half of next week.
Longer range computer forecast guidance suggests the potential for another Arctic air outbreak out of the polar regions of northwest Canada by about nine or ten days down the road.. specifically the Saturday and Sunday/18-19 January 2014 time period. I’ll continue to monitor this situation and will keep you informed.
Regarding my forecast, my local forecast confidence: My confidence in my forecast is high through tomorrow and tomorrow night. For the weekend through the middle part of next week, my forecast confidence rises to very high.
Have a good Thursday…
Meteorologist Troy Kimmel