Some Heavy Storms Yesterday

Mountain storms occurred a bit further to the west yesterday and produced some rain over the high-elevation stations across the eastern part of the Pima County ALERT network (24-hour coverage - 18 of 92 stations). Graphic below shows lightning strikes detected for past 24-hours ending at 6 am MST this morning. Most of the storms were again off to the east, but note that were CGs in the Catalinas, Rincons and along a swath that started in the Santa Ritas and ran off toward Benson. The White Tail site along the Catalina Highway caught a local downpour and reported a total of 2.16" - just over 2 inches of this fell in less than an hour. Nothing again at low elevations and not even a sprinkle here at house for 7 days now. There was a strong outflow from the east across parts of town around 4 to 5 pm during the afternoon.

The morning run of the WRF-GFS indicates Pacific flow dominating, with CAPE vanishing by early afternoon across most of southeastern Arizona. Precipitable water amounts have fallen below an inch at all the southern Arizona sites except for the southeastern corner. The model forecasts bring the PW back up over an inch during the day on Wednesday, as some moisture returns from the south.

Water vapor image from 6 am MST (above) shows very dry upper-tropospheric air over Arizona and southern California. An inverted trough in the lower troposphere along the west coast of Mexico has resulted in early morning storms over the southern portions of the GoC. Lightning strike data from Mexico for 12-hours ending at 6 am this morning (below) show a high strike-density across the mouth of the Gulf.

The current time series of GPS PW from the Atmo page, above, show the dryness over southwestern Arizona that extends down the GoC past Hermosillo, which still has PW less than inch. At 8 am MST this morning Hermosillo reported a temperature of 88F with a dewpoint of 36F - ugh! The Hermosillo time series of PW will be a good indicator of when low-level moisture returns up the GoC. Meanwhile hot and dry conditions prevail.