DUST DEVIL DASH OUTLOOK – SAT SEPTEMBER 9, 2023
Issued: 1230pm Wed 09/06

Walter Rogers WX

The Southwestern U.S. will be under the influence of a light 500mb WSW flow 25-30kts over the Sierras and a warm core high over SE Arizona SW New Mexico. That high is expanding westward with a ridge line to near San Diego bringing with it a surface temp warming trend and suppressed marine layer along the Southern California coast. The soaring pattern will provide moderate thermal activity near Tehachapi and over the Sierras… benign fair weather cu starting around 2pm bases 13-15k msl rising to isolated near Boundary Peak and Basalt mid afternoon at 17.5k msl. North and West of Bishop skies will be mostly clear all the way to the Reno Carson City area.

Skysight is showing 3-4kt thermals beginning over Double Mtn around 11am… thermal heights 10.5-11.5k msl by 130pm Double, Cache Pk and the Walker Plateau with cu developing. It looks best to transition to the Inyos and Whites because Skysight (and the GFS with which it is initlaized) represents mid level altocumulus over the Sierras. This is remnants of a distant tropical storm.

Route Planning – The traditional Owens Valley route north looks best staying over the White Mtns… then veering NW toward the Carson Valley. Routes NE from Boundary Peak look good also, but run the risk of water/mud on most of the dry lakes (note the 7 day cumulative rain totals on the Dropbox weather board). The other routes: 1) East to Barstow, Las Vegas SW Nevada; too much mud/water on dry lakes 2) Southeast to Mt Baldy Big Bear and south to Mexican border (Jacumba); Interesting and doable if you can cross over to Crystal high enough to climb out 3) W and NW up the coastal ranges; Weakest route especially NW of Avenal to Byron.

I’ve created a “Dropbox Weather Board” for viewing graphics and Skysight views:

bit.ly/DDD23_WeatherBoard

Continue to monitor this weather board and email for updates…

Walt Rogers WX