These small fluffs of Cumulus clouds above Ms. Mt. Sara Lemmon, were the first indications that something good, and very different from the previous two days was going to happen yesterday. These clouds appeared no less than 4 h earlier in the day (between 9 and 10 AM yesterday) than those first Cumulus on top of the Catalinas on the previous two days.
The correct emotional response due to this early rising for cloud maven juniors and doscents out there should have been excitement and anticipation; that some big boys with long names (Cumulonimbus capillatus incus) were likely going to be around later in the afternoon and evening hours. No weather maps needed! See AZ Star for confirmation.
While we didn’t get a big dump right here in Catalina, we did at least get a dust-coagulating 0.02 inches. Here are the totals ending at 24 h from around the region from the Pima County Alert gages. The most hereabouts was at the Santa Cruz River at Ina Road with 0.59 inches, with that storm shown in the photo at 4:25 PM below.
Today, with dewpoints once again being in the upper 50s, it should be the case that we see these early precursor clouds on top of Mt. Lemmon, and they will once again lead to the conclusion of a satisfying day of thunder and intense rainshafts, driven by 100 F plus temperatures. It peaked at 106 F here yesterday in Catalina, and it was fairly cloudy when that temperature was recorded! Pretty remarkable.
Here’s your NWS computer generated forecast for Catalina, foretelling similar temperatures for today.
Here are some later shots of those great clouds, and if you want the whole nine yards, go to the U of A time lapse movie here. There’s a lot of rotation at the bottom of some clouds 1:03 before the movie finishes, and an indication of a rope-like funnel cloud, not too surprising given the instability of yesterday.
Maybe today, with plenty of clouds and heat, it will be our day to get the big dump and wash the dust off our desert plants.