Updated 845am CDT Thursday / 26 September 2013
…. A Dry and Stable Weather Pattern Continues ….
…. A Cold Front Approaches Late Saturday into Sunday with a Chance of Rain ….
On this Thursday morning…. a high pressure area is over the northeastern USA. A low pressure area is over eastern Colorado with a trough.. or line.. of low pressure extending south southwestward through eastern New Mexico. As a result of this surface weather pattern, surface winds are becoming southerly over our area.
In the upper levels of the atmosphere… a trough.. or line.. of upper level low pressure is moving slowly eastward through the northeastern USA with another.. much stronger.. upper level low over southern Idaho with broad upper level trough over the western third of the country. An upper level high extends from south Texas into the northwestern Gulf of Mexico. As a result, the upper level winds over south central Texas and the Austin metro area about 18,000 feet above the ground are south southwesterly 10 to 20 mph.
As indicated by the continued clear sky overhead, the dry and stable weather pattern prevails across the area.
By tomorrow into Friday, with surface high pressure well to the east, a south southeasterly surface wind will become reestablished across the area with an increase in low level moisture.
By late Saturday into Sunday, the strong upper level low over the intermountain west will move eastward and, as a result, a southeastward moving cold front will move into Texas with scattered rain showers and thunderstorms expected across the area. Forecast rainfall amounts have increased a bit with the latest guidance suggesting between 1 to 2 inches of rain locally between 7am Saturday and 7am Monday.
Once the front passes around midday or early afternoon Sunday, rain chances and clouds will decrease with more sunshine.. lower humidity and slightly cooler temperatures for Sunday night and into next week.
The tropics are quiet with no tropical cyclone development expected over the Atlantic basin over the next 24 hours.
Regarding my forecast, my local forecast confidence: High to very high forecast confidence through the next seven day forecast period.
Have a good Thursday…
Meteorologist Troy Kimmel
Contact me:
tkimmel@austin.utexas.edu
http://www.facebook.com/troykimmel