An Update On The Monsoon Season With KNAU Meteorlogist Lee Born

Jul 23, 2014

KNAU's Morning Edition host Aaron Granillo talks monsoon activity with meteorlogist Lee Born.

A monsoon storm opens up over the red rocks of Sedona.
Credit Al Comello/The Sedona Eye




Aaron Granillo: We’re about a month into the monsoon season and it’s started of pretty wet, at least here in Flagstaff. The last week or so it’s been kind of dry. Explain why that’s happening.

Lee Born: You’re exactly right, Aaron. It did start off pretty robust there when it started raining right around the fourth of July. Went through a two week, three week period where we saw very widespread rainfall amounts of one to three inches across northern and central Arizona, which is just fantastic because we had one of the driest, first halves of the year on record. So we were really anxious for the rain to start.  And then we’ve been in a slow down here. That’s pretty typical for the monsoon to come in waves. Some periods are wetter than others for sure.

Why does that happen? Why does all of the sudden the monsoon decide to take a break?

What happens is the monsoon moisture gets pushed out of the state. And when we’re in the monsoon season much of it flow is out of the south and east, bringing in all that tropical moisture off the Gulf of Mexico and also out of the Gulf of California. But when we get a little push of westerly air in the monsoon often comes in breaks like this. Or we call it bursts when we get a bunch of moisture in place and we go into an active period. So, right now the moisture has been pushed off into New Mexico but it’s slowly creeping back in here.

We’re here in Flagstaff, where it was really, really wet at the beginning of the month. What about the rest of the region? Is it feeling the same impact that we are here in Flagstaff?

Often the way the monsoon is, it’s a little bit here and a little bit there. Some people get the love and others don’t. But it usually spreads itself out and evens itself out over a two-and-a-half-month time period. So, Prescott is over an inch of rain and right around average. Winslow at a half inch is right about average. Now if you look at Page, on the other hand, they’ve gotten less than a tenth of an inch of rain and are very dry. But, I would bet to say by the ends of the season it will all have evened out and hopefully we’re all at least at average.

Let’s talk about dryness because you talked about at the beginning of this conversation how we’ve been in a bit of a dry spell for the year. How is this monsoon helping in terms of dryness and the drought that this region has been experiencing?

The first half of the year – January through June – was the ninth driest first half of the year on record for us here in Flagstaff. I think it was the third driest in 100-plus years of record keeping. Now that the rain has come, it’s helped somewhat. It’s certainly helped in the short term. We’re not as dry and the fire danger has gone way down. But we’re still seeing the long term trend being more critical as far as our drought goes. And If we get a decent monsoon that will relieve it somewhat, but we’re so early in the monsoon it hasn’t had a chance to really do it. I was just looking at the U.S. drought monitor before we had this conversation and nearly 100 percent of the state of Arizona is in a moderate drought. 75 percent of the state is in a severe drought.

So it’s been a break for a couple of days here, it’s been pretty dry. What about this week? I guess maybe some thunderstorms, rainstorms, may be rolling through the region?

Well moisture is gradually creeping its way back in. The flow is becoming more southerly and easterly and we’re already seeing a few showers and thunderstorms across the White Mountains and they’ve  creeped into the eastern Mogollon Rim. Today I think we’re going to see them all across a good portion of the Mogollon Rim country and northern Arizona. And then scattered to isolated showers and thunderstorms right into the coming weekend. It’s not so wet that I think we’re going to see a lot of rain down in the deserts of Yavapai and Gila counties so much.