Updated 915am CT – Wednesday / 28 January 2015
…. Sunshine and Warmer Temperatures Continue ….
…. Series of Cold Fronts Bringing Much Cooler Temps by Tomorrow and Beyond ….
…. Clouds Thicken with Rain Chances By Friday Through the Weekend ….
On this Wednesday morning…. surface high pressure is situated from the Ohio Valley region southward through the lower Mississippi valley. Developing low pressure is located over the central plains from South Dakota southward into Kansas with a trough.. or line.. of low pressure extending southwestward into west Texas. High pressure is located.. to our west.. over the four corners region. As a result of this surface weather pattern, our local surface winds are light westerly.
In the upper levels of the atmosphere.. a deep trough.. or line.. of low pressure is situated from Maine into the western north Atlantic Ocean off the east coast of the USA. A stationary upper level low pressure disturbance is over the eastern Pacific Ocean off the west coast of Baja Peninsula. Another stronger trough.. or line.. of upper air pressure is well west of the USA west coast over the open Pacific Ocean. As a result, our upper air winds at about 18,500 feet are westerly at 10 to 20 mph.
A dry and stable air mass remains in place with some high clouds at or above 25,000 feet dominating. This pattern will continue through the next day or so with afternoon temperatures running about 15 degrees above average for this time of year. In fact, record high temperatures area likely today in the Austin area with existing long term record highs for the 28th day of January being in the upper 70s and probably easily broken today with forecast highs around 80.
By late tonight into Thursday, we’ll see a stronger surface cold front surge southeastward across Texas with cooler air moving into the state. The cooler surface air mass will be reinforced by additional surges of cooler air moves in through the weekend.
Most importantly, however, a series of Pacific upper level low pressure disturbances will track eastward across the southwestern USA and northern Mexico into Texas beginning late Thursday into Friday and through the weekend. This will cause moisture to “overrun” the surface cooler air and clouds and thicken and lower quickly beginning late Thursday and Thursday night with rain chances returning for late Friday through Friday night and through the weekend as well. This will result in a chilly and wet weather pattern for the weekend into early next week. At this point, it looks like surface air temperatures will remain above the freezing mark which means liquid precipitation. Early guidance suggests, on average, about an inch of rain area wide with this system.
Regarding my forecast, my local forecast confidence: My forecast confidence is very high through tomorrow with my forecast confidence falling back to medium to high for Friday through the coming weekend (rain chances, timing and amounts being issue).
Have a good Wednesday….
Meteorologist Troy Kimmel
Contact me:
tkimmel@austin.utexas.edu
http://www.facebook.com/troykimmel