Updated 845am CT – Friday / 11 April 2014
…. Southerly Winds and Increasing Humidity ….
…. A Cold Front with Widely Scattered to Scattered Thunderstorms Late Sunday ….
…. Clearing Skies and Cooler Temperatures Early Next Week ….
On this Friday morning…. surface high pressure /1024mb/ is off the east coast of the USA. A cold front extends southwestward from the Ohio Valley region into central Oklahoma and west Texas and eastern New Mexico. As a result of this surface weather pattern, our local surface winds are southerly.
In the upper levels of the atmosphere… a general west to east.. or zonal.. flow continues over the USA as a strong area of upper level low pressure is approaching the California coast from the Pacific Ocean. As a result of this upper air wind pattern, the upper level winds over south central Texas and the Austin metro area about 18,000 feet above the ground are west northwesterly at 25 to 35 mph.
Southerly surface winds continue to bring low level moisture northward into the area with even some patchy fog and drizzle in some areas this morning. An increasing moist weather pattern will continue to dominate the area over the next couple of days.
By Sunday into Sunday night, as the air mass overhead becomes increasingly unstable and as the upper air disturbance off the coast of California moves eastward through the Rockies into the plains, we’ll see a rather strong cold front move through the state. Locally, the front will move through the area sometime about daybreak on Monday morning. This is a little later than some of the guidance showed in recent days with the upper level low pressure slowing a tad in its forward forecast movement. As it approaches, we’ll see widely scattered to scattered rain showers and thunderstorms beginning as early as late Saturday night but more likely Sunday into Sunday night then peaking as the front moves through early Monday. Meteorologists at the NWS/Storm Prediction Center in Norman, OK have “outlooked” parts of north and east Texas… mainly northeast of Austin.. for a possibility of a few severe thunderstorms during this period.. I’ll continue to monitor this possibility.
Once the front passes, much cooler and drier air will once again move into the area as winds shift northerly as surface high pressure settles into Texas from the plains states.
By Wednesday of next week, the surface high pressure area with its clockwise circulation will move east of the area and a return southerly surface wind will begin to return low level moisture to the area. Early guidance suggests that we may see enough atmospheric instability for a slim chance of rain showers by Thursday night into Friday.
Regarding my forecast, my local forecast confidence: My forecast confidence is very high for today.. tonight and Saturday. My forecast confidence falls to medium to high (reference rain and thunderstorm chances, the possibility of severe weather and the exact time of the cold frontal passage) by Saturday night through Sunday.. Sunday night as well as Monday. My forecast rises back to very high in the wake of the cold front for the early and mid part of next week.
Have a good Friday…
Meteorologist Troy Kimmel
Contact me:
tkimmel@austin.utexas.edu
http://www.facebook.com/troykimmel