Updated 845am CDT Monday / 28 October 2013
…. A Moist Air Mass in Place Across the Area ….
…. A Strong Upper Air Storm System / Cold Front Due Mid Week ….
…. A Round of Rain Showers and Thunderstorms as System Passes ….
On this Monday morning…. a surface high pressure area is over the southeastern USA with a cold front extending southwestward from the southern Great Lakes into northern Kansas into Colorado and Wyoming. A trough.. or line.. of low pressure extends south southwestward from a surface low along the cold front over western Kansas and eastern Colorado. As a result of this surface weather pattern, surface winds are south southeasterly across our area.
In the upper levels of the atmosphere… a southeastward moving strong upper level low pressure area is over the Reno/Lake Tahoe area of western Nevada and eastern Colorado. An otherwise zonal (west-to-east) flow continues across the rest of the USA. As a result, the upper level winds over south central Texas and the Austin metro area about 18,000 feet above the ground are westerly at 30 to 40 mph.
On this Monday, a warmer than normal moist weather pattern continues across south central Texas as a south southeasterly surface wind persists across the area.
As the upper low out west moves eastward by later tomorrow into tomorrow night and Wednesday, the inflow of moisture from the south and southeast will increase as will atmospheric instability and lift. As a result, we’ll see rain shower and thunderstorm chances increase by late tomorrow night and especially later Wednesday into Wednesday night. Some periods of heavier rain are possible.. especially Wednesday night.. as the upper air system, moves by to our distant north. Current NWS guidance suggests than upwards of 1 to 1 1/2 inches of rain could fall over our area Wednesday into early Thursday.. isolated heavier totals are certainly possible.
As the upper system passes, an associated cold front will be allowed to drop through the area on Thursday morning with high pressure.. cooler and drier air.. and clearing skies taking hold late week through the weekend.
Regarding my forecast, my local forecast confidence: High forecast confidence through Thursday (some break in the clouds and exact timing of rain chances being the confidence reducing factors) then very high confidence for Thursday night and Friday through the weekend.
Have a good Monday…
Meteorologist Troy Kimmel