SignalsAZ.com Prescott News Podcast - Understanding Arizona’s Monsoon: Safety, Science & Storms with NWS and ERAU Experts

Episode Date: May 30, 2025

Send us a text and chime in!Join Talking Glass Media’s Elicia Morigeau in a fascinating conversation with two top weather experts—Megan Taylor, Warning Coordination Meteorologist for the National Weather Service in Flagstaff, and Dr. Curtis James, Professor of Meteorology at Embry-Riddle Aeronautical University.In this in-depth interview, they break down the science behind Arizona’s monsoon season, from what causes those dramatic afternoon thunderstorms to how ocean temperatures and snowpack impact their intensity. You’ll also learn about the crucial role of the National Weather Service in issuing watches and warnings, how they work with partners like transportation departments, and what safety steps you can take to stay prepared.Check out the CAST11.com Website at: https://CAST11.com Follow the CAST11 Podcast Network on Facebook at: https://Facebook.com/CAST11AZFollow Cast11 Instagram at: https://www.instagram.com/cast11_podcast_network

everybody, welcome back to cast 11. I'm Alicia and I'm joined today with the knowers of all things on soon season. So I'll let you guys introduce their titles are very tricky. So sure. Hi, my name is Megan Taylor and I'm the warning coordination meteorologist with the National Weather Service in Flagstaff. Awesome. Hi, I'm Curtis James. I'm a professor of meteorology at Embry-Riddle Aeronautical University. How do I get so lucky to spend the afternoon with super smarty people over here because I like those. So warning coordinator, what does that mean? Good question.

So as part of the National Weather Service, our mission is to protect life and property. So we are the government agency that issues all of the weather warnings, watches warnings and advisories. So if you ever get a flash flood warning on your cell phone, that's us. A severe thunderstorm warning, that's us. A winter storm warning, that's us. So it is my job to coordinate all of the information that we're sending to our partners that we work with Closie. Those would include folks like ADOT, Department of Transportation, city and county emergency management,

people that are using our information a lot to make weather decisions. So it's my job to coordinate with those folks and make sure that we're getting them the information they need. So when something big is happening, what, you know, a big storm or something, when you're contacting AdDOT, what are some of the things that they might do? You know, are they closing down highways? Are they, you know, what are, what are some things that you're saving us from? Yes. So ADOT is our biggest partner when it comes to winter and snowfall. And anyone not familiar with Northern Arizona, we do get a lot of snowfall flagstaff averages about 90 inches a year, which is, yeah, a lot of people are surprised by that.

And so it is very impactful to the highways and interstates around the area. So A-DOT is always using our forecast information to try to decide how to treat the roads, how to, they're usually not closing the roads until after the snow has fallen. Okay. But they're using that information to try to decide how to best treat the roads and when, and then how to staff up for their resources to be able to keep up. And I would think, too, like flash flood warnings. you know, you see all the time those people that are, oh, it said don't cross, but I'm in a big

truck. I'm going to be okay. Those are you guys that are, you know, saying, hey, don't do that. Yes, exactly. So any weather warning that you see comes from the National Weather Service. And then we also issue watches and advisories as well. So we have all kinds of products that we issued to try to keep the public safe. And a lot of our information is what you see broadcast on, say, your local TV station. If they're putting up weather information, say a winter storm watch, that's us. Okay. So were the government entity basically providing the information and it's used by media,

it's used by academia, it's used by all kinds of anybody. It's public information. It's used by a lot of weather apps. If your weather app shows you a winter storm warning, it's coming from us, essentially. So we're not getting it from there. There's actually people behind that because I just think, oh, the ops are so smart. They know everything's going on. But that's fed by real human means, right?

Yeah. Awesome. And then the real reason, why we've called you here today, is talk about monsoon season. So at Embry Riddle, this is something of your expertise, correct? And so. Yes. We've done a lot of research on the monsoon. We continue to do that.

But the monsoon comes from an Arabic word mausim, which means season. So it's just a seasonal wind shift. It's the most consistent part of our climate because every single year the wind will shift because of a difference between the heating of the continent and the oceans. So the wind shifts and becomes more of a southerly from the south direction, bringing moist air from the subtropics into Arizona, leading to showers and thunderstorm. So this happens every year, typically towards the first part of July, but some years it comes early, late June, and some years it comes later by mid, late July sometimes. Why do they always hit in the afternoon?

The atmosphere is more unstable during the afternoon because of solar heating. Oh, great. That's the most common reason why it's more likely to happen in the afternoon. So are you able to really, you know, kind of pinpoint how great the monsoon season is going to be or how? Because I love a great monsoon season. I think we all do and most of us anyway. But how, what are some predicting factors that kind of lead you to believe this is going to be a great monsoon season or this is going to be a drier monsoon season? Well, pinpoint is a strong word because for climate predictions, it's really, there's a lot of different variables involved.

But we oftentimes base it on ocean sea surface temperatures. And this is done mostly by the storm or the, sorry, the climate prediction center of the National Weather Service. They also have some predictability based on snowpack and that sort of thing. Okay. So they'll give you a probability that's going to be greater or less than normal. So how are we looking right now? that's the question on everybody's minds. Well, we have a figure that we'd like to show you that shows that currently the outlook for July through September is more likely to be wetter than normal than drier than normal.

That's good. That's really good. And that just goes on to, you know, just with, because we had kind of a drier summer or winter, but then spring, we got, I think, more rain over spring than we did during winter. So I remember when I lived in California by force. It wasn't by choice. I heard words all the time like El Nino and El Nina. And I was like, oh, it's El Nina. It's going to be.

But is that real? Like, that's real stuff going on. That's also related to sea surface temperatures. Did you want to talk about that? Sure. Yeah. Yeah, all of it's really tied together. El Nino is called the El Nino, Southern Oscillation.

And it is based off of tracking that we do of ocean temperatures way down in the Central Pacific Ocean. So we're talking like near the equator. Okay. And we track these ocean temperatures because believe it or not, they actually do impact the weather here in the United States. It's a very far distance away from us, but it does impact our weather patterns. And what we typically see is during an El Nino, which is when those waters are warm, it can have an effect to, kind of bring the jet stream further south. And so the storm track is more south in the United States. And so that's why here in Arizona, we can see wetter winters during that period of the jet stream

being further south. Conversely, La Nina is when those waters are cold. And we tend to see the jet stream further north. We kind of get this blocking ridge of high pressure that sits over the west coast. and that a lot of the storms just go to the north. That's kind of what we were seeing the early part of this season is a lot of those storms staying north. But then, like you said, this spring, we had kind of an active pattern. We started to see those storm systems drop further south, and we ended up with an okay spring.

So we're in this weird year where we had a very, like, historic dry winter, followed by an okay spring. And now we're headed into fire season. and it's bought us a little time to have a little moisture, but the reality is the snowpack was non-existent this year, so potentially could see still a pretty significant fire season. All that to answer your question about monsoon season, and to my understanding, it's more in the cool season

that El Nino is tied to precipitation patterns, not as much during monsoon season. Okay. So there's other things like Curtis talked, about the circulation between the landmass. So the landmass heating differently than the ocean is driving that monsoon circulation. So we're relying more on that heating to take place to drive the monsoon than we are El Nino, if that makes sense. It's not as much of a player during the summertime. So why, though, Arizona, I mean, are there other states that have a monsoon

season? Because I know in California, we did not get, you know, a monsoon season. So is it just Arizona? Is it other states? We tend to refer to it as the North American monsoon because it is affecting portions of Mexico as well. And the moisture is coming up from the Gulf of California. And it does affect much of the southwest, even parts of California sometimes. I just missed it probably. So Arizona, New Mexico, it'll creep into Utah and Colorado.

Sometimes it'll slosh over into Nevada and parts of California. Even a strong surge might even make it up to, say, Wyoming on a really, you know, good surge of moisture. So it does affect much of the southwest, not just Arizona. I love a good monsoon when we're inside. You know, you always see it coming. You can feel it coming. And so it's like, get into the market or whatever you need to do to get your shopping done and get home before it hits. And how many times have we been in the middle of stores drys can be?

And you walk out and it's like, how am I going to get to my car? But it's with that, I love watching it, but I bet you they're pretty dangerous, especially with such a dry, you know, winter and spring that we've had. I bet it can wreak some havoc, especially the first couple monsoons that hit. No, that's correct. There are a number of hazards associated with monsoon thunderstorms. You mentioned dryness. Well, early on, the monsoon on the air is still somewhat.

dry and hot and you add moisture to that, then you tend to have high base thunderstorm. So the thunderstorms tend to develop with a high cloud base. And that gives plenty of distance for falling precipitation to evaporate or partially evaporate before it gets to the ground. And this leads to what we call microbursts, which are really concentrated down drafts that can really cause squirly winds and even wind damage down near the surface. I've had one of those take my trampoline far, far away. And it just, you have no idea of like it's coming. And we've had the trampoline was staked down. And it actually ripped the top off the trampoline and sent it just flying.

But, and I mean, this is an average. Those got to be very difficult to predict that those are coming. They're very difficult to predict. You know the conditions are there. But it's very difficult to predict where it's going to happen. We measured a record wind gusts at Ember Riddell on the roof of our building. of 83 miles an hour last summer as I watched out my office window and saw the trees getting knocked over by the wind.

So that was just from a microburst within a mile or two from our office. So they're very localized. They can develop very suddenly within one to two minutes. And they're just very concentrated down drafts. I remember that day that it was just I had, I coached cheerleading. I had a gym full of little kids. And it went from, oh, I think a monsoon's coming to power hitting out. Little's are screaming and they're crying because the winds are just, they're so loud.

And it just happened so fast. And you're like, it's okay. And you're trying to be so brave because you can't get them panicked. But there's been some doozies. There's also a flash flood potential. Our thunderstorms here can be quite localized, but can produce rainfall rates up to even four inches per hour. And so on sandy surfaces or surfaces have been recently burned by wildfires, those soils

don't absorb the moisture very well. And so it tends to run off very quickly. So that's a major source of damage from the monsoon. And then recently we've seen a lot of larger, large hail events, you know, one inch diameter or larger is considered damaging hail. and we've seen some events like that in recent years. Yeah. Exciting to watch, but sometimes, and all too often you hear of, you know,

people that are down in rivers or lakes and then, you know, a monsoon hits way over here and it just starts driving these waters into these, you know, rivers. And it's, you hear too many, too many stories of that sort of thing going on. So I've caught some really good questions to ask you guys, because name me, do you know, I'm sure you do. What are three of your most fascinating facts about monsoon season? I'm throwing you for a curb ball here. I can start with one.

I don't know if I can do three off the bat. And I'll pose it as a question first. So how much water do you think it takes to move a vehicle? We're talking about flash flooding. And we're always trying to encourage people never to drive through a flooded area. could have washed the road away, lots of dangerous. There could be debris in there. So we always like to ask that question.

I would assume probably 18 inches at least to get a car moving. That's a good guess. It could be as little as 12. It's typically 12 to 18 inches can sweep away a vehicle. And that includes a big truck. Yeah. And I was like guessing at 18 because you would think like I've seen puddles, you know, and everybody underestimates those.

I mean, you see them go through. them. I was driving home and our road was just gone. There's just water everywhere. And, you know, I drive a little car. I was like, I can make it through there. And I didn't. I just was like, you know, we stayed back, but it was 18 inches can take away a big old 12 to 18 inches. The problem is how, how do you know how deep it is, that muddy water moving across the roadway. Oh, because I've driven this road a thousand times. And if it's a dirt road, it maybe has washed the road away. So the road isn't even really there anymore. You don't know what's underneath there. That is a good point. Yeah. And I think that's a really good point because how many of us live,

you know, I cross this road every, you know, 10 times a week. It's, I know these roads like the back of my hand, but such a little bit of water can take away a whole car. That is super scary. Well, I can add another fact to that now that we're talking about it and it jogged my memory. So flooding is the second most weather-related killer in the United States. And of the flooding fatalities, how many of those do you think are caused by people and vehicles? I wouldn't think that many. I would think it'd be more of just people that are caught in the river or the lake. Nope, it's over 60%.

It's like 63 or 64% of flooding deaths are caused by folks and vehicles. And I would assume a lot of those are operator error or bad judgment. Yeah, I mean, it's hard to know, right? Yeah, we think so. I mean, you're making the decision to get into harm's way and whether or not you misjudged it or maybe you were in the waterway and another flood came through and it just rose another two feet. So that's that's, you know, another danger of it is you don't know what's coming.

You're making your decision based on what you see right in front of you, but you don't know what's coming from upstream. Well, and I've even had to pull over because you can't see in front of you. The water is coming down so fast and so heavy and so just out of nowhere. I remember going down like Willow Lake Parkway, and there's like a little turnoff, like a little business that has a garage overhanging. And I went parked under there because it was just getting so bad. But I mean, how many people are just like trying to get over to the side but don't see it? And they're getting, you know, cars are running into them. It's scary, scary.

And everything in monsoon season happens so quickly. Like you've alluded to many times already, you know, a thunderstorm can develop in the matter of 30 minutes. So like you said, while you're in the store, it's developed. You come out and it's crashing down. So it is, yeah, it's kind of like a tumultuous time of year. It's a wonderful time of year. It's beautiful, but it is very dangerous, too. Absolutely.

Anything you want to add on interesting, cool facts? Well, our group has done a lot of research on trying to improve predictability of monsoon thunderstorms. We've found that Yawapai County, or down here in central Yavapai, we have a much lower probability of prediction of thunderstorms than up on the Moghion rim, which is the ledge of terrain between. southern Arizona and northern Arizona, that's where the thunderstorms oftentimes first develop. And so the models predict the first initiation or development of the thunderstorms better than their organization and motion towards these lower-lying areas in Yabai County. And so one thing that we found, which is really interesting, is that the soil moisture is actually the number one predictor of where those thunderstorms are going to pop up next.

We're still trying to identify how that is and working to improve the forecast models so that they can better predict the thunderstorms. But that's the number one fact that I've been focusing on. And so we're developing a machine learning-based model that we're going to, we can share it with your viewers. And we're also going to share it with the National Weather Service that will use machine-based. you know, the different variables such as soil moisture and other predictors to try to improve on the predictions we already have. That's, it is just wild to me how mother nature is just, we've been around for how long and we're still trying to figure out, figure out why these things are happening and where they're,

you know, how to pinpoint them, as I, you know, mentioned before. But, um, and we're at Embry-Riddle, yet this is what you study, right? So is the other weather and patterns, just only monsoon? What is the? Well, we're focusing a lot on, I focus a lot on mountain meteorology, but right now our main focus has been on the monsoon and trying to improve prediction. We're hoping and planning to do a field campaign where we would bring instrumentation from other research groups to Northern Arizona and do a field project, hopefully in

the summer of 2027 to try to collect the data we need to make those improvements to the models. So we know it's coming. We're hoping it's going to be a good monsoon season just for the sake of water. I always hear my husband say things like, oh, that's a good soaking rain because it's, you know, the sprinkle and it's been around for. Do we get a lot of precipitation from, is it good water when you're getting this much water in a short amount of time? Is it really doing us good as far as like drought numbers and drought levels? I would say the monsoon precipitation doesn't add too much to our water reservoirs a lot of that evaporates off very quickly after an event and since it's so localized usually the runoff just kind of spreads out and evaporates along those river just dry washes and river beds so I think what what it does is just keeps the plants alive if we didn't have a monsoon I don't think we'd have very many plants and animals that could survive. the summer here.

We wouldn't have the forest that we have in Arizona. So the monsoon just keeps everything alive. It's the winter precipitation that really soaks into the ground and really fills the reservoirs. So it does have a purpose, though. It keeps things kind of moving along, especially in places where nobody's out there watering stuff and nobody's getting to these animals and putting water out for them. As we know it's coming, what are some steps we can take to keep ourselves safe during monsoon

season. You said they're right. I did. I'm learning. I would say, you know, number one is being prepared yourself. So you're checking the forecast before you head out. You don't want to be caught off guard, you know, on a big thunderstorm day when you had no idea there was even a possibility of a storm producing 60 mile per hour winds.

So, you know, always stay up to date with the forecast, whether that's your weather app or website, weather.com, whatever your means are, you know, TV media, stay informed. Make sure you know those days when say we have a flash flood watch out, which means that conditions are favorable for those storms to produce heavy rain. And those are the flash flood days. So we want you to know in advance, that's what the purpose of a flash flood watch is. Those are the days you want to stay out of the creeks and streams, you know, maybe plan your hike for a different day or do it really early in the morning. So it's really the planning aspect that we try to get people in that mindset of planning ahead, know when the threat is there and postpone your activities. I didn't think about that.

I always think of the people in the water already, but just people that are on a regular hike, you know, it can cause pretty big damage on those. Yeah, absolutely. Recreating, you know, in a little wash or a stream that, you know, 90% of the year, it's just fine. But, But if you hit it on a bad day and two or three feet of water comes rushing through there, you're going to be in trouble. So just knowing when the potential is there on those potential flash flood days and trying to limit your risk, really, like limit your exposure to dangerous conditions. One of our sponsors for the monsoon article is a roofer because we thought that was perfect because we see shingles ripped off the roofs. And so before monsoon season, probably have all that stuff inspected, make sure gutters are cleaned out, all that good stuff because it's, I mean, so much rain and just, I mean, how many inches do you think we get in a good monsoon? I would say it depends on where you're located because it really depends on the elevation, the close you are to the south side of town by the Bradshaw Mountains.

We're going to have more frequent thunderstorms. And as you go northward towards Chino Valley, Pauld, then you're going to have less. So it depends on your elevation where you're located relative to the mountains because the mountains initiate the thunderstorms. That's right. But I'd say anywhere from an average of maybe four inches in the lower lying areas to maybe eight to ten inches up in the mountains. It would be an average or slightly above average monsoon. And you just wouldn't think, you know, it's like with flash floods, I always think, oh, that happens other places. It's not going to happen here.

And you just, I mean, to have that much precipitation happen in such a short amount of time. And then the lightning and... Yes. We didn't even talk about lightning. I almost brought that up earlier. We should because... Yeah. When we first visited here, we took a boat.

We were getting in a boat and we were taking it out onto one of the lakes. I don't even know. And everybody was... You know, sky was getting a little darker and we were like, oh, whatever. And people in droves coming back to the dock. And we're just like, because we were visiting from, you know, that other place. And all of a sudden, like, here comes the wind and the lightning. And it's like, oh, this is what's going.

on, but everybody seems to know except, you know, people that visit. But what are some of the things that you see from the lightning? I'm assuming that can't be. It's very dangerous. And I mean, we don't issue a lightning warning. So you have to know that any thunderstorm is going to produce lightning. And if you're in the wrong place at the wrong time, you know, we see fatalities every year in Arizona from lightning. We actually are in the top 10 states for a lot of Lightning fatalities, yeah. And so a lot of that is just that preparedness piece and not putting yourself in the wrong place at the wrong time, you know, trying to do your hikes early in the morning.

We know that thunderstorms initiate over the mountains first. So get down before 11 a.m. And, you know, I'll be honest. I've been caught in it too. I love hiking and I love a destination hike and I've been caught on top of the mountain and I forgot to check my warnings for that day. You know, and I know it. But still, it happens so quickly that it can be, yeah.

It's, and like you said, too, it's hard to predict sometimes, you know, especially in our area, just, right there's. And, you know, lightning doesn't just go straight down. It can branch out and it can strike even up to 10 miles away from the core of the thunderstorm. But you can kind of gauge how far away the lightning is if you count how many seconds between when you see the lightning and you hear the thunder and divide that by about by five, because the speed of sound is approximately one mile in five seconds. I didn't know to divide.

So yeah, divide by five. So if it's 25 seconds between the lightning and the thunder, it's five miles away. So if I count to five, that's a mile away. Yes. And I've always thought, oh, I count to five, it's five miles away. We're good. No, no. I did not know to divide by five.

It's a cool part which he explained this already, but because the difference in how, in speed of light versus sound. so lights traveling five times faster than sound so you're seeing the lightning before you hear the thunder it's such a beautiful experience i mean we've all watched the thunderstorms and they're so beautiful to watch and then but also can be deadly and you know just like you say a good point plan your your hikes early i worked out of a golf course and the guys were out there golfing and yeah it's like don't it's their metal yes i used to Tell him when you see a monsoon start rolling in, just take your golf clubs.

And the guy was like, I said, I am joking. Do not do that. And he was like, but one, the one guy was like, oh, I didn't. I was like, no, I am, come on, man, don't do that. And he's like, okay. But I was like, so we'd have to, you know, be smart for people. It's starting, we're closing the course. You need to come back in.

Yes. Diehard. Pools in the summer. I think a lot of places are getting better about that now that lightning data might be available on an app or something, but, you know, closing the pool, we're not going to have people in the water when there's lightning in the vicinity. I think people are getting better about that. But yeah, it's really just making sure you're not in those situations. And, you know, I hate to say it, but the reality is there is not a safe place to be outdoors.

There are some things you can do to try to mitigate your risk, like not being the tallest object around, not standing right under a tree that might attract the lightning strike and then travel to you. Which I would think go under a tree. Be safe under the tree. Right. Just get inside. There's so many things to think about. Inside a vehicle or an enclosed shelter or safe places. As long as the windows are up, the doors are closed,

as long as you don't have an open window in a building. And we're not trying to cross a path. Just hunker down and wait for the storm to pass. Yes. Enjoy the show. Yes. And it's not the rubber tires, as a lot of people think on the car that protects you. I was going to say we're grounded.

We're the rubber tires. It's the metal cage around you. It's that fair. a cage of the metal. So if you're riding a bike, you're not safe because you're the tallest object on top of a metal frame. You guys are teaching me so much because one, divide by five, would never, I just always thought it was forever far from storms. And I've always thought it was the rubber tires. And I just, I threw out the 18 inches because I like, I bet it's really a lot lower than I think, because I would think it would be, you know, waist high to carry around

a vehicle. So be prepared. Do your stuff early in the day, especially if it requires hiking or, you know, being up near mountains. Just be smart, right? Just because we all think we're invincible, right? But yes. Weather is, she's. And know that there's multiple risks. From one thunderstorm, you could be looking at lightning, hail, flash flooding. So there's a lot to think about. And that's why it's best to just mitigate, you know, your exposure in susceptible areas. But yeah, there's a lot of things that can happen. Welcome to Arizona. And damaging winds as well.

But tornadoes are a lot more rare here, but they can happen. They're called Lanspout tornadoes. We usually get weaker ones. But they are, they are relatively common in Arizona, but they're not as strong as you would see in the Midwest or the, southern plains to southeast U.S. But I was going to mention that if we do have

tornadoes, they tend to be later in the summer, maybe towards September, October, when the winds start to get stronger in the upper atmosphere. That's what tends to create your tornadoes. And those are probably not enough to pick a cow up and take it across the pasture, but you know, maybe, really? Not usually.

But we've had up to EF3 tornadoes in areas. Really? Yeah. Which is 100, 65 mile per hour. Yeah. And believe it or not, there was actually a little spin-up landspout tornado here in Prescott Valley about two weeks ago. We got a video.

I don't know if you saw that. I did see a video of that. It was a school. It was after school. It let out. It was before 5 o'clock. But we had video of it. Yeah, you could see the circulation and it took some shingles right off of the school.

Yeah. Oh, my gosh. A little unusual for me, I will say. Well, I left. earthquakes to face season. But we love it. It's pretty, just be smart,

enjoy the show of Mother Nature. And what is your website again to keep on top of all of this? Yes. Our website is weather.gov forward slash flagstaff. Perfect. Perfect. And I think I've learned a ton talking to you guys. You guys sent in graphs.

So we'll get those out to our readers and our listeners. and I just appreciate you guys so much because I know I joke about, you know, I'm going to ask, but you really taught me a lot today because I just, I just see rain. It's like, oh, a monsoon. That's great. So I appreciate you guys coming in. And as always, thank you guys for tuning into Cast 11 podcasting. And we will see you next time. Thank you.