Updated 845am CDT Wednesday / 17 April 2013
A Strong Cold Front with Thunderstorms Possible Late Tonight/Early Tomorrow ….
Much Cooler Temperatures Return By Tomorrow ….
A Weekend Warm Up in Store as Southerly Winds Return ….
On this Wednesday morning…. a stationary front extends west southwestward from the Missouri bootheel through Arkansas and Oklahoma and the Texas panhandle and then into a deepening surface low pressure area over southern Colorado. A cold front extends southward from the surface low through New Mexico. Given this surface pressure pattern, surface winds are southerly across our area of Texas.
In the upper levels of the atmosphere…. a broad area of upper level low pressure over the northwestern USA has consolidated into a sharp and deep trough extending from Montana south southwestward into southeastern California. Given this upper air pattern, winds over south central Texas and the Austin metro area about 18,000 feet above the ground are southwesterly 25 to 35 mph.
Southerly surface winds continue to bring moisture northward from the western Gulf of Mexico. This basic weather pattern will continue through tonight into early tomorrow. Clouds could break a little today by late morning today with afternoon sunshine getting afternoon high temperatures well in the 80s.
By tonight (after midnight) into early tomorrow.. a strong cold front will move southeastward through Texas with scattered rain showers and thunderstorms likely just ahead of the front as it moves through the area. At this point, I think the cold front will pass over the Austin area in the mid morning hours tomorrow with the best instability and atmospheric lift remaining to our distant north and, as a result, the highest rain chances and the threat of severe weather generally remaining to our north. In addition, time of day.. being the morning hours.. is also a negative for severe weather. Locally, I think we could see between 1/4 and 1/2 inch of rain with this systems passage.
Drier and cooler air will move down into our area by tomorrow midday and afternoon through tomorrow night into Friday. Surface high pressure will move east of the area by the weekend with a southerly wind.. warmer temperatures and a little increase in cloud cover and humidity by late Saturday through Sunday and into early next week.
Have a good Wednesday night and Thursday…
Meteorologist Troy Kimmel