Updated 915am CT – Friday / 15 December 2017
… Clouds and Rain Chances On the Increase Into the Weekend …
… Back to Sunshine by Early to Middle Part of Next Week …
… Longer Range Guidance Still Suggesting Colder Temps and
Precipitation for the Pre-Christmas Weekend …
On the Weather Map…
On the surface map… a weak cold front is settling slowly southeastward from the southeastern USA into the northwestern Gulf of Mexico and then into deep south Texas and northeastern Mexico. As a result of this surface weather pattern, our surface winds across south central Texas are north northeasterly.
On the upper air map… a broad trough, or line, of upper level low pressure covers the eastern two thirds of the USA. Within the upper level counterclockwise flow around the trough, a dynamic low pressure disturbance is slowly moving east southeastward from the central plains into west Texas and northwestern Mexico. As a result of this upper air weather pattern, the 30,000 foot winds over our area are southwesterly at 120 to 130 mph.
What I am Seeing As I Look Ahead…
We’ve continuing with some upper level cloud cover as the very strong subtropical jetstream winds overhead (with winds of 120 to 130 mph from the southwest) race northeastward. We’ll see those high clouds come and go today.
By tonight and continuing through tomorrow into tomorrow night, the upper level trough, or line, of upper level low pressure out west will move overhead of our Austin and south central Texas area. As it does, we’ll see a more dynamic atmosphere develop with abundant atmospheric lift with rain showers and even a few thunderstorms become more widespread tomorrow into tomorrow night. Rainfall of 1/4 to 1/2 inch is possible with the passage of the upper air storm system.
As the system passes, we’ll see the return to at least some sunshine Sunday into the first part of next week as another cold front passes early Monday. While there looks like some cloud cover will linger until the front moves through the area Monday but I am not mentioning any rain chances at this point.
The middle part of next week looks dry and a little bit warmer.
Looking ahead.. beyond the seven day forecast period.. we continue to watch the numerical forecast guidance as it continues to strongly suggest a trend toward colder weather and wetter weather pattern once we get into the weekend before Christmas. At this point, that is about all I’ll mention as precipitation chances are still quite uncertain and vary widely among the models. I would caution everyone from getting carried away with any given forecast solutions that you may see in social media since this is still 7 to 9 days away. Given the fact that many people will be traveling during this upcoming holiday period, you can be assured that I will be watching the forecast pattern closely for you.
Have a good Friday….
Meteorologist Troy Kimmel
Contact me:
tkimmel@austin.utexas.edu
http://www.facebook.com/troykimmel
—
Updated 845am CT.. Friday / 15 December 2017
TODAY…. Partly cloudy. High 59. Northerly wind 5 to 10 mph.
TONIGHT…. Becoming cloudy. Low 40. Light northeasterly wind becoming light and variable late.
SATURDAY…. Cloudy and cooler. Scattered rain showers developing in the morning and then scattered rain showers and even a few thunderstorms in the afternoon with an associated lightning risk. A 50% chance of rain; where rainfall occurs, rainfall will average 1/4 inch. High 53. Light wind becoming south southeasterly 4 to 8 mph by afternoon.
SATURDAY NIGHT…. Cloudy with rain showers likely. A few thunderstorms possible with an associated lightning risk. A 70% chance of rain; where rainfall occurs, it will average 1/4 inch. Rainfall tapering off after midnight. Low 44. South southeasterly wind 4 to 8 mph becoming more westerly late.
SUNDAY…. Decreasing clouds early becoming mostly sunny. High 67. Southwesterly wind 4 to 8 mph.
SUNDAY NIGHT…. Becoming partly cloudy as a weak cold front passes after midnight and toward daybreak. Low 47. Southerly wind becoming northerly 5 to 10 mph after midnight.
MONDAY…. Partly cloudy. High 65. Northerly wind 5 to 10 mph.
MONDAY NIGHT…. Partly cloudy. Low 43. Light northeasterly wind.
TUESDAY…. Mostly sunny. High 67. Northeasterly wind 5 to 10 mph.
TUESDAY NIGHT…. Mostly clear. Low 44. Light easterly wind becoming southeasterly after midnight.
WEDNESDAY…. Mostly sunny and a little bit warmer. High 69. Southerly wind 5 to 10 mph.
WEDNESDAY NIGHT…. Mostly clear. Low 48. South southeasterly wind 5 to 10 mph.
THURSDAY…. Mostly sunny. High 71. Southerly wind 5 to 12 mph.
NATIONAL WEATHER SERVICE / 8 TO 14 DAY OUTLOOK
Valid Friday / 22 December 2017 through Thursday / 28 December 2017…
Temperature… Well Below Average
Precipitation… Well Above Average
AUSTIN SUNSET/SUNRISE TIMES…..
Sunrise this morning (15 December)………………………………. 7:20 am
Sunset this evening (15 December)………………………………… 5:32 pm
Sunrise tomorrow (16 December)…………………………………… 7:20 am
Sunset tomorrow (16 December)……………………………………. 5:33 pm