What a great cloud day yesterday was with thunder on the Catalina Mountains by 10 AM. It seemed so promising for a major rain here in Catalina. But no, shafts to the left, shafts to the right. In fact, we were “surrounded” on three sides by shafts at times, but only residuals of those shafts got here to produce a measly 0.04 inches! Still, it was nice to see those cloudbursts out there drenching something.
Here are a few photos of yesterday’s clouds, beginning with a 9:44 AM morning shot, once SO FILLED WITH PORTENT. I remember how happy I was! Look, the bases of the Cumulus clouds are touching the top of Table Mountain! Think how warm they must be, maybe 12 F (50 F)! And we remember that the WARMER the cloud base, the more easily they rain! Also note ice falling out of the right side of the top of this cloud in the first photo. Imagine, at 9:44 AM, those towers were already able to ascend to the level where its cold enough for ice to form, and you know what that means, RAIN falls out! Yay!
Below, is an example of that assertion about rain and ice. First, a cloud (cumulus congestus) whose top has already reached that level where ice forms–look how different it appears in that highest sprout in the middle of the photo, how smooth it looks compared to the crenellated, cauliflowery look in the turrets below. But there is NO rain falling out yet. That conversion to ice has just happened. The much higher concentrations of cloud droplets are being replaced by much lower concentrations of ice particles, and that’s why you can visually detect this change in appearance. The lower concentrations of ice make the cloud look a bit less detailed in top structure.
While that highest portion is already converting to ice, you still see no shaft. This is a great moment to impress your friends with some razzle dazzle conversational meteorology: “Hey, guys, that cloud is gonna have a helluva shaft of rain in just a coupla minutes!” It would be a magical moment for you.
How long will it be before you see a rain shaft? Only about two minutes! And here, in that first shaft shown in the next photo two minutes later, are where the largest rain drops and sometimes hail will be found. You don’t want to go over the speed limit, but under this type of cloud BEFORE the shaft is out the bottom is where you should be to see some real rain excitement, that is, rain bouncing about 6 inches off the pavement, but you’ll have to pull over, maybe some close lightning strikes, too.
Finally, a typical afternoon shot of the rain shafts around Catalina, in this instance, looking toward Twin Peaks.
Man, that was a fun day yesterday for cloud viewing!