STEVE GOLDSTEIN: Mark, that is the sound I heard last night in my backyard. And unlike the previous day, where I thought it was my ice machine in my fridge, I knew it was rain this time, how about you?
MARK BRODIE: Yeah, I guess better late than never, right, for these, for these monsoons. Yeah, we had a pretty spectacular lightning show last night. We were standing outside trying to capture pictures of it on iPhones. Unsuccessfully.
GOLDSTEIN: Well, and with us now to give us some actual knowledge of what happened last night is Matt Pace, meteorologist for the Arizona Department of Environmental Quality. Matt, welcome back.
MATT PACE: Yeah. Thank you. And it's an exciting time to be here after a little bit of rain finally during monsoon.
GOLDSTEIN: Yeah, we were very excited. So when I was talking to one of our colleagues here, Phil Latzman, before our show, and I said, "OK, how did your neighborhood go?" Phil lives 3 miles from me, Matt. I got six-tenths of an inch. He got .06. So how did that happen?
PACE: Yeah, and that's always the trick with monsoon. They're so spotty, but at least everyone got the lightning show. And what we saw yesterday is, is two thunderstorm complex — their outflows actually converged over the Valley. And that's why we saw those very severe thunderstorms that really started up in the North Valley and then moved their way kind of down the 17. And the heaviest spot, surprisingly, was actually right around Sky Harbor, where they picked up .9 inches of rainfall, which helped us. But then one rain gauge, even at the I-17 and Carefree Highway, 1.38 inches. And then right next door, about a half mile away, absolutely nothing. So it just shows you how spotty the rain is. But overall, 51% of the Valley did see measurable rain, which is great news.
BRODIE: Matt, I want to ask you about the wind, because that seemed to be really, really gusty last night. In fact, several trees in my neighborhood were, were bowled over, including a fairly large tree. How, how fast did the wind blow last night?
PACE: They were pretty strong. There were some reports, especially at the Glendale airport, of wind gust of 60 miles per hour, and some locations likely saw even higher gusts than that. And that's one of the things we traditionally see with these thunderstorms. You know, those cloud bases are are pretty high up in the atmosphere, and as that rain falls, it cools that air and then that crashes down into the ground and quickly spreads out and you see those microburst winds that can easily be 60, 70, even 80 plus miles per hour at times.
GOLDSTEIN: So, Matt, you know, of course, the big question is, "Well, we finally got some rain last night. So what does that mean for the next few days?" But how unpredictable was last night, in fact, not that there will be some clouds and maybe some wind, but the fact that there was all this measurable rain? How difficult, really, when it comes down to it, is it to predict a monsoon from night to night?
PACE: So monsoon is a tricky season to start forecasting, especially because you're dealing with these outflow interactions that if we didn't have those come together over the Valley, the chance of rain would have been minimal yesterday. But since we saw those storms to the east, the storms to the north converge over the Valley, the chances quickly go up. Now, the benefit was we actually had a surge of moisture. You probably felt it yesterday, really humid out there. That was a surge of moisture coming up from the Gulf, from Hurricane Genevieve that we've been tracking right off the coast of Baja. And that helped those thunderstorms sustain off the mountains, because over the past couple of days, we've been kind of teased with the thunderstorms to the north and the east, but there wasn't enough moisture in the Valley. So as soon as they dropped off the high country, they completely fizzled out. We were left with just some wind. So today the cloud cover is going to hurt us just a little bit. We're not going to see as much heating around the state. But then as we head into Saturday, Sunday, we could actually start to see some more activity move into the Valley.
BRODIE: Matt, just anecdotally, stepping outside this morning it was still fairly humid out. I mean, does that tell us anything about what to expect, even if it's just maybe slightly lower temperatures over the weekend?
PACE: It does certainly tell us that when you step outside, it's going to feel a lot hotter than it actually is. So the good news is our temperatures are going to come down this weekend. But unfortunately, with all that humidity, the heat index is going to be much higher. So it is going to feel humid. But as we continue to feel that humidity outside, that is going to give us that better chance of those storms coming off of the mountains into the Valley. Any of these storms that do form are going to be able to produce a lot of lightning and a lot of rainfall as well. In fact, the National Weather Service actually had an interesting stat that 90,000 cloud-to-cloud lightning flashes were seen across Arizona yesterday. So certainly the rain's exciting and the lightning is exciting as well.
GOLDSTEIN: Matt Pace, meteorologist for the Arizona Department of Environmental Quality. We always appreciate your time, Matt. Thanks. Stay safe.
PACE: Thank you.
