Updated 915am CT – Friday / 19 May 2017
.. An Unsettled Weather Pattern Continues ..
.. Best Rain Chances Saturday through Saturday Night ..
.. Another Storm System with Rain Chances Monday into Tuesday ..
On this Friday… a surface low pressure area is over southern Kansas with a cold front extending southwestward into western Oklahoma through the southern Texas panhandle and the northern south plains of west Texas then into northeastern New Mexico. A dry line.. separating dry air to the west from moist and tropical air to the east.. extends from its intersection with the cold front over the southeastern Texas panhandle south southwestward into far southwest Texas. As a result of this surface weather pattern, our surface winds across south central Texas are south southeasterly.
In the upper levels of the atmosphere, a deep upper air low pressure trough, or north to south line of low pressure, covers the western 2/3rds of the USA with a strong disturbance embedded within the trough over the four corners region. As a result of this upper air weather pattern, the 30,000 foot winds over south central Texas are west southwesterly 35 to 45 mph.
The broad upper air low pressure trough, currently located over the western 2/3rds of the USA, has continued to contribute to a more moist and unstable air mass overhead.
We’ll continue to see scattered rain showers and thunderstorms today through tonight.. with the highest rain chances and the strongest thunderstorms remaining to our north, northwest and west.
By tomorrow into early Sunday, the strong upper level low pressure disturbance out west and the trough of low pressure overall will move northeastward into the plains states. This will allow a surface cold front to move southeastward across the IH35 corridor by tomorrow night into the predawn hours Sunday. Abundant atmospheric lift will combine with the rich low level moisture and an unstable atmosphere to produce scattered to numerous rain showers and thunderstorms particularly after mid day tomorrow through the early morning hours on Sunday. Periods of heavier rain are possible over the area.
The cold front will weaken later Sunday through Sunday night along and offshore of the Texas coast with rain chances decreasing (but not disappearing completely) locally as the front pulls up stationary in the Texas coastal waters.
By early Monday and continuing into early Tuesday, another strong upper level low pressure disturbance will approach the area from the west with the front off the Texas coast returning quickly northwestward as a warm front into our area. As the warm, moist and more unstable air mass returns and the low pressure area approaches from the west, I will quickly increase rain shower and thunderstorm chances again by early Monday and continuing into early Tuesday as another cold front sweeps eastward through the area.
As always, a reminder that lightning, associated with any thunderstorms that develop or move into the area over the next few days, will pose a danger. Updated guidance continues to suggests upwards of 1 to 3 inches of rain locally with isolated heavier amounts to over 4 inches over the next four days.
In the wake of the front, skies will partially clear as more stable, slightly cooler and drier air takes hold for Tuesday night and Wednesday into Thursday next week.
Have a good Friday….
Meteorologist Troy Kimmel
Contact me:
tkimmel@austin.utexas.edu
http://www.facebook.com/troykimmel
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Updated 845am CT.. Friday / 19 May 2017
TODAY…. Morning low clouds, otherwise partly to mostly cloudy with widely scattered rain showers and thunderstorms with an associated lightning risk. A 20% chance of rain; where rainfall occurs at any given location, it will average 1/4 inch or less. High 92. South southeasterly wind 8 to 15 mph.
TONIGHT…. Mostly cloudy with scattered rain showers and thunderstorms with an associated lightning risk. A 30% chance of rain; where rainfall occurs at any given location, it will average 1/4 inch or less. Low 74. South southeasterly wind 8 to 15 mph.
SATURDAY…. Mostly cloudy with scattered rain showers and thunderstorms in the morning becoming more numerous in the afternoon with an associated lightning risk. A 40% chance of rain in the morning increasing to 50% in the afternoon; where rainfall occurs at any given location, it will average 1/4 inch. High 88. South southeasterly wind 8 to 15 mph.
SATURDAY NIGHT…. Cloudy with numerous rain showers and thunderstorms with an associated lightning risk. A 60% chance of rain; where rainfall occurs at any given location, it will average 1/2 to 1 inch. Low 70. South southeasterly wind 8 to 15 mph becoming more south southwesterly after midnight.
SUNDAY…. Mostly cloudy with numerous rain showers and thunderstorms with an associated lightning risk as a weak cold front moves southeastward through the area by sunrise. Rain chances decreasing midday into afternoon with the sky becoming partly to mostly cloudy. A 60% chance of rain before 8am decreasing to 20% by afternoon; where rainfall occurs at any given location, it will average 1/4 inch. High 83. Winds becoming northeasterly 5 to 10 mph as the front passes.
SUNDAY NIGHT…. Mostly cloudy and a little cooler with widely scattered rain showers. A 20% chance of rain; where rainfall occurs at any given location, it will average trace amounts. Low 64. Light northeasterly wind.
MONDAY…. Mostly cloudy with scattered rain showers and thunderstorms with an associated lightning risk. A 50% chance of rain; where rainfall occurs at any given location, it will average 1/4 to 1/2 inch. High 84. Light easterly wind becoming south southeasterly by late afternoon.
MONDAY NIGHT…. Mostly cloudy with numerous rain showers and thunderstorms with an associated lightning risk. A 60% chance of rain; where rainfall occurs at any given location, it will average 1/4 to 1/2 inch. Low 70. South southeasterly wind 5 to 10 mph.
TUESDAY…. Mostly cloudy with numerous rain showers and thunderstorms with an associated lightning risk as a cold front passes before 9am. Rain chances decreasing by afternoon. A 60% chance of rain before 9am decreasing to 20% by afternoon; where rainfall occurs at any given location, it will average 1/4 inch. High 84. Southerly wind 8 to 15 mph becoming northerly by midday into early afternoon.
TUESDAY NIGHT…. Mostly cloudy and a little cooler with widely scattered rain showers before midnight. Decreasing clouds after midnight becoming partly cloudy. A 20% chance of rain; where rainfall occurs at any given location, it will average 1/10th inch or less. Low 63. Northerly wind 5 to 10 mph.
WEDNESDAY…. Mostly sunny. High 80. Northerly wind 5 to 10 mph.
WEDNESDAY NIGHT…. Mostly clear. Low 59. Light northeasterly wind.
THURSDAY…. Mostly sunny. High 84. Light winds becoming southeasterly 5 to 10 mph.
NATIONAL WEATHER SERVICE / 8 TO 14 DAY OUTLOOK
Valid Friday / 26 May 2017 through Thursday / 01 June 2017…
Temperature… Slightly Below Average
Precipitation… Near Average
AUSTIN SUNSET/SUNRISE TIMES…..
Sunrise this morning (18 May)……………………………………………. 6:35 am
Sunset this evening (18 May)……………………………………………… 8:20 pm
Sunrise tomorrow (19 May)………………………………………………… 6:34 am
Sunset tomorrow (19 May)…………………………………………………. 8:21 pm