Updated 845am CST Tuesday / 5 November 2013
…. Clouds and Rain Chances Peak Tonight into Tomorrow ….
…. Upper Air Low Pressure System and Cold Front To Move Through Mid Week ….
…. Plenty of Sun.. Drier and Cooler Weather Due Late Week into the Weekend ….
On this Tuesday morning…. a cold front extends southwestward from the Great Lakes as it becomes a stationary front over northern Missouri then a warm front into a low pressure area over northern New Mexico. A cold front extends from the low southwestward through southwestern New Mexico and southern Arizona. Surface high pressure is over the northeastern USA. As a result of this surface weather pattern, surface winds are south southeasterly across our area.
In the upper levels of the atmosphere… a slowly eastward moving upper level low pressure trough.. or line of low pressure.. extends southward from Montana into Arizona. As a result, the upper level winds over south central Texas and the Austin metro area about 18,000 feet above the ground are strong southwesterly at 40 to 50 mph.
As the upper level low pressure trough west of us moves slowly eastward out of the western USA, it has strengthened and has continued to return low level moisture to our area and, at the same time, bringing upper level moisture and clouds from the Pacific Ocean northeastward over Texas. In other words, we’ve continued to “prime” our atmosphere for another rainfall event as the upper level low pressure trough moves overhead by tomorrow and then northeastward away from the area late week.
This forecast rainfall event.. based on the latest NWS rainfall forecast guidance.. will, in general and on average, likely yield another 1 to 2 inch rainfall across the area with isolated heavier totals. This could cause additional localized flooding problems in areas especially where we’ve seen heavy rain in the last few weeks.
Once the upper level low pressure passes, an associated cold front will surge southeastward across the area by tomorrow afternoon. Clouds will break quickly and rain chances will drop from the forecast in the wake of the front.
Drier and cooler weather with abundant sunshine will prevail for Thursday and Friday and through the weekend.
Clouds will increase again by the early part of next week as south southeasterly surface winds return to the area.
Regarding my forecast, my local forecast confidence: High to very high forecast confidence through mid week (a little uncertainty regarding exact rainfall amounts) then very high confidence late Wednesday through Friday and the weekend.
Have a good Tuesday…
Meteorologist Troy Kimmel
Contact me:
tkimmel@austin.utexas.edu
http://www.facebook.com/troykimmel