Monday, July 16, 2018

Second Half July - Starts With High PW

View of Catalinas above is from 8:00 am MST yesterday showing one of the several bands of light showers that moved north-to-south across eastern Pima County during Sunday morning. Photo below is from Saturday (July 14), early afternoon showing heavy shower just north of Mt. Wrightson over the Santa Ritas.

The morning showers yesterday produced 100% areal coverage of rainfall, but with generally very light amounts. Here at house we added 0.20" to the total July amount, so far, of 0.55". The plot of detected CG flashes (below from Atmo and Vaisala for 24-hours ending 2;30 am this morning) indicates very little thunderstorm activity across almost all of southern half of Arizona. The were several flashes over the Sky Islands early yesterday.

This morning the PW remains well above an inch and a half (was 80F with high RH here at 6:30 am); however, winds aloft are light and there is limited CAPE this morning. The 500 mb analysis for 12 UTC (above from SPC) shows the huge ridge across southern 2/3rds of CONUS, with generally light winds. There is an inverted trough (IT) separating the two main centers of the anticyclone, with weak steering winds from the east over Arizona. There are also indications that cooler mid-level temperatures temperatures may sneak in today, increasing afternoon CAPE, especially for areas that get some sunshine. The 250 analysis (below, also from SPC) indicates a very pronounce, upper-tropospheric IT from western edges of Texas south-southeastward across Mexico. This feature will shift westward next couple of days, bringing increased storm activity, particularly over northern Mexico, and perhaps southern Arizona. Meanwhile, our sauna-like conditions continue.

1 comment:

  1. Bob, I don't think CAPE is too bad. The sounding had around 800 J/kg MLCAPE which is fairly good. Far SE Arizona (Paradise) is really getting skunked so far. I've had less than an inch. So much for the "Gap".