Updated 915am CT – Wednesday / 08 March 2017

… Cloud Persist in an Overrunning Pattern …
… A More Unsettled Weather Pattern by Late Week into the Weekend …
… Our Next Cold Front Late Saturday Night into Early Sunday Morning …

On this Wednesday… a cold front extends southwestward from central Georgia and southeast Alabama to the mouth of the Mississippi River into the northwestern Gulf of Mexico then inland again over far south Texas and northeastern Mexico. Surface high pressure, north of the front, is located over western Tennessee, northern Mississippi and eastern Arkansas. As a result, our surface winds across south central Texas are easterly.

In the upper levels of the atmosphere, a trough, or line, of upper level low pressure extends south southeastward from Hudson Bay through the Great Lakes and northeastern parts of the USA. An otherwise rather zonal (west-to-east) upper air wind pattern prevails across most of the USA. As a result, the 30,000 foot winds over south central Texas are westerly at 50 to 55 mph.

In the wake of yesterday’s cold front, the shallow wedge of surface based cooler air overhead this morning – only a few thousand feet deep – is being overridden by moist southerly flow off the northwestern Gulf of Mexico. We’ve even see a few sprinkles over the area this morning. With the surface high pressure area, north of the front to our distant southeast, well to the east of the area, we’ll see our surface wind return to the south southeasterly by later this afternoon into tonight.

As these southerly low level winds return, a corresponding low level moisture return takes place through the weekend. However, with a more zonal (think, west-to-east) forecast upper air wind pattern, I do not see any big air mass changes through Saturday and Saturday night. Clouds will increase with a few rain showers for late week then a better chance of rain showers and thunderstorms by Friday through Sunday morning ahead of an approaching upper air low pressure disturbance from the west and an associated weak surface cold front that will “backdoor” its way into our area from the north northeast.

The developing and passing upper air disturbance and associated cold front will move across the area just after midnight Saturday night with cooler temperatures and a more stable air mass taking hold Sunday (with more sunshine) with increased clouds again Sunday night into Monday in advance of a second reinforcing weak cold front, again more from the north northeast, Monday night into Tuesday. Clouds will break once again by Tuesday with the passage of the second cold front.

Have a good Wednesday….
Meteorologist Troy Kimmel

Contact me:
tkimmel@austin.utexas.edu
http://www.facebook.com/troykimmel

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Updated 845am CT.. Wednesday / 08 March 2017

TODAY…. Mostly cloudy with a few sprinkles. A 20% chance of rain. Rainfall, where it occurs, will average trace amounts. High 69. Light easterly wind becoming southeasterly 4 to 8 mph by mid and late afternoon.

TONIGHT…. Mostly cloudy with patchy fog developing after midnight. Low 62. South southeasterly wind 4 to 8 mph.

THURSDAY…. Patchy morning fog otherwise mostly cloudy with a few rain showers and isolated thunderstorms.. with an associated lightning risk.. mainly after 12 noon. A 20% chance of rain. Rainfall, where it occurs, will average 1/4 inch or less. High 77. Southerly wind 5 to 10 mph.

THURSDAY NIGHT…. Mostly cloudy with a few rain showers and isolated thunderstorms. A 20% chance of rain. Rainfall, where it occurs, will average 1/4 inch or less. Low 66. South southeasterly wind 4 to 8 mph.
FRIDAY…. Mostly cloudy with scattered rain showers and thunderstorms with an associated lightning risk. A 40% chance of rain. Rainfall, where it occurs, will average 1/4 inch or less. High 78. South southeasterly wind 5 to 10 mph.

FRIDAY NIGHT…. Mostly cloudy with scattered rain showers and thunderstorms with an associated lightning risk. A 30% chance of rain. Rainfall, where it occurs, will average 1/4 inch or less. Low 64. Southerly wind 4 to 8 mph.

SATURDAY…. Mostly cloudy with scattered rain showers and thunderstorms with an associated lightning risk. A 40% chance of rain. Rainfall, where it occurs, will average 1/4 inch or less. High 78. South southeasterly wind 5 to 10 mph.

SATURDAY NIGHT…. Cloudy with scattered rain showers and thunderstorms with an associated lightning risk as a cold front passes after midnight. A 50% chance of rain. Rainfall, where it occurs, will average 1/4 to 1/2 inch. Turning cooler after midnight. Low 55. South southwesterly wind 5 to 10 mph shifting north northeasterly after midnight.

SUNDAY…. Decreasing clouds early becoming partly cloudy. Cooler and less humid. High 69. North northeasterly wind 5 to 10 mph.

SUNDAY NIGHT…. Increasing clouds becoming mostly cloudy. Low 54. Northeasterly wind 4 to 8 mph becoming more easterly after midnight.

MONDAY…. Mostly cloudy and a little warmer. High 76. Southeasterly wind 4 to 8 mph.

MONDAY NIGHT…. Mostly cloudy with a cold front passing by about midnight. Low 57. South southwesterly wind becoming northeasterly 5 to 10 mph.

TUESDAY…. Decreasing clouds early becoming partly cloudy. High 73. Northeasterly wind 4 to 8 mph becoming more easterly by afternoon.

NATIONAL WEATHER SERVICE / 8 TO 14 DAY OUTLOOK
Valid Wednesday / 15 March 2017 through Tuesday / 21 March 2017…
Temperature… Above Average
Precipitation… Near Average

AUSTIN SUNSET/SUNRISE TIMES…..
Sunrise this morning (08 Mar)……………………………………………. 6:49 am
Sunset this evening (08 Mar)……………………………………………… 6:35 pm
Sunrise tomorrow (09 Mar)………………………………………………… 6:48 am
Sunset tomorrow (09 Mar)…………………………………………………. 6:36 pm