Sunday, October 21, 2018

An Active Storm Day Today - October 21st

Santa Ritas at sunrise yesterday were shrouded by a large cap cloud. No storms in southeast Arizona yesterday afternoon, but strong east winds of 30 to 40 mph were bringing in low-levl moisture from New Mexico. The Mt. Hopkins RAWS gusted to 45 mph , while the airport here hit 41 mph. The plot of detected CG flashes (below from Atmo and Vaisala for 12-hours ending 6:45 am MST this morning) indicates morning storms northwest of Phoenix. More widespread thunderstorm activity was associated with Hurricane Willa off coast of Mexico.

There are towering Cu here and there this morning, as per view to north from Kitt Peak.

Closed low portion of West Coast Rex block (500 mb analysis above for 12 UTC this morning from SPC, as is skew-T analysis below) will slowly progress eastward across the Southwest next several days, bringing chances for more rains and storms here. The morning sounding shows several interesting structures. East winds have increased low-level moisture below 800 mb, but this layer is rather stable. However, southerly winds above have brought in middle-level moisture and CAPE that is impressive. The strongly veering, Plains-type, wind profile favors strong to severe thunderstorms, with 30 to 40 mph steering winds from the southwest. Second below is current 12 UTC WRF-RR forecast of composite radar echoes valid at 4:00 pm this afternoon - if forecast models are accurate both this afternoon and tomorrow will be very active with strong to severe thunderstorms and possible hail.

Meanwhile to south, Hurricane Willa is strengthening south of Cabo Corrientes. The morning forecast from NHC indicates a landfall by midweek near Mazatlan.

No comments:

Post a Comment