Updated 845am CT – Tuesday / 6 May 2014
…. Increasing Low Level Moisture Leads to Rain Chances ….
…. Clouds on the Increase ….
On this Tuesday morning…. surface high pressure is over the northeastern Gulf of Mexico.
A developing low pressure area is over southwestern Kansas /992 mb/ with a stationary from extending east-to-west through it from central Missouri and Kansas then northwestward from the low into northeastern Colorado and Wyoming. A trough.. or line.. of surface low pressure extends southward from the low into western Oklahoma then into west and far southwest Texas. As a result of this surface weather pattern, our local surface winds are southerly.
In the upper levels of the atmosphere… a developing counterclockwise rotating trough, or line, of upper air low pressure extends from Alberta south southwestward to eastern California and western Nevada. The upper level winds over south central Texas and the Austin metro area about 18,000 feet above the ground, are west northwesterly 20 to 30 mph.
Surface southerly surface winds have been quite efficient over the last 24 hours in returning low level moisture to our area. Late night and early morning low cloudiness will be prevalent over the coming days with an otherwise partly to mostly cloudy sky.
By Thursday and Friday, an upper air low pressure disturbance will approach and move into the southern plains along with a weakening cold front with increasing atmospheric lift and instability being the result. While I expect the best atmospheric lift to remain well to the north of the local area, widely scattered to scattered rain showers and thunderstorms will still be possible locally with late week rainfall amounts to 1 inch possible. The cold front will have a hard time making it to the Austin area with it washing out overhead of our local area early Saturday.
We’re looking at a return to a partly cloudy sky for the area by Saturday afternoon through Sunday into the first half of next week.
Regarding my forecast, my local forecast confidence: My forecast confidence is very high today through tomorrow night. My forecast confidence falls back to low to medium for the Thursday through Friday night time period reference rain chances, rainfall timing and rainfall amounts which I am still uncertain of at this point. My forecast confidence for Saturday into Sunday and early next week is back to high to very high.
Have a good Tuesday…
Meteorologist Troy Kimmel