An extraordinary June 16th

Not only did Tucson set a daily record for rain on June 16th with 0.29 inches, breaking the old record of 0.20 inches that fell in 1918 (!), but here in Catalina, the 0.11 inches was the first measurable rain on June 16th in the 35-year combined record maintained at Our Garden, and then here for the past few years.

It was only the second day with measurable rain in Catalina since mid-April, and that prior rain was only a paltry 0.01 inches that fell in mid-May.

Regional rainfall totals for yesterday’s magnificent day can be found here, courtesy of the Pima County Flood Control District.  Two sites in the Catalina Mountains got hit hard, with 0.94 inches at Pig Spring, and a whopping 1.54 inches at CDO at Coronado Camp.  Those two gages are close to one another near the top of the CDO watershed.  Here is a map having those locations.  You can also get 24 h rain totals, ending at 7 AM today, from the U of A network here.

The best part, though, may have been those desert aromas that spring out of the desert when it rains,  and that cool air that rushed around Catalina yesterday afternoon and evening.  Makes you happy to be alive.  However, those two close lightning strikes were somewhat unsettling when you’re running around outside with a camera..

The drop in temperature as the rain hit was stupefying, about 35 degrees, from 100 F to 65 F!

Here are some photos, since I am still alive, the first ones of the Altocumulus perlucidus clouds that were mutating into Cirrus uncinus, a bit of an oddity.  The TUS sounding indicates that these droplet Altocumulus clouds were extremely cold, -30 C (-22 F).  And their presence was another live demonstration about how odd ice formation is in the atmosphere, still not completely understood.

By late morning the Cumulus were sprouting over the Catalinas, and the Altocumulus/Cirrus were gone. Those Cumulus clouds were a great sight since the models had very little rain indicated, and these were fattening up nicely suggesting those models might not have gotten “the scene” for yesterday right; there was more hope for rain after all.

Ice clouds on the left, droplet clouds on the right side.
Parhelia (sun dog) in the fallstreak of a former Altocumulus flake.
1:16 PM: Cumulus mediocris, center right, portends a good shower day.
2:11 PM. We are underway!
2:32 PM: Heavy rain falls on the upper CDO wash watershed.
3:01 PM: A strong shower complex appeared to the S toward TUS, giving hope of some rain here.
3:02 PM: Two very strong dust devils developed ahead of the outflow winds coming into Marana. They seemed odd since they were under the cloud cover and you start looking up to the base to see it there is a tube up there, and whether it is one of the dry tornado funnel cases.
3:09 PM. The thunderstorms over the Catalinas propagated to the west and here Saddlebrooke gets a dump.
7:33 PM: After our nice little rain, and as happens so often here in the summer rain season, we polish the day off with a spectacular sunset.
























The weather ahead

The next chance for rain, the best one I could find, of course, is next Friday and Saturday afternoons. For Friday afternoon, this, from the U of WA’s model.  The lightly colored, filled in areas represent rain.

Looking for just Cumulus today, maybe a very isolated Cumulonimbus cloud.