The Heat Is On...Again
SPEAKERS
Jim du Bois, Kenny Blumenfeld
Jim du Bois 00:00
We wish there was another way to say it, but it's dry. This is Way Over Our Heads. It's a weather and climate podcast. I'm Jim du Bois. Kenny Blumenfeld's a climatologist. Kenny, kind of a haze hanging over things today on Wednesday, July 21. How is that making you feel? I'm a little hazy myself today, I think because of that haze.
Kenny Blumenfeld 00:24
Yeah It's ah, it's kind of an eerie feel out there, especially the odor because you're really smelling smoke from fires in Manitoba and Ontario that have drifted in on the winds aloft and then get mixed down. You know, I guess, today, as we're recording, it's not as hot as it's been, and it's not as hot as it's about to be. So, I guess I'll take that. That's fine. But yeah, I could do without the kind of apocalyptic feel of all that smoke in the air.
Kenny Blumenfeld 00:57
You also?
Jim du Bois 00:58
Yes, exactly. And the haze is limiting temperatures a bit, too. It would be warmer today, wouldn't it, if not for that haze?
Kenny Blumenfeld 01:06
Oh, yeah, we've actually had several days now where smoke and haze have probably limited the temperatures by up to five, five degrees Fahrenheit or so. So, you know, even over the previous weekend, there was a milky haze in the sky. That was a combination of actual haze, and the particulates drifting in from some of the farther afield fires that were burning. And those did conspire to keep the temperatures, you know, I don't know if you remember all the way back on the weekend, but we actually had been forecast to be at well above 90 degrees initially, and those didn't happen, and much of Minnesota ended up in the high 80s because of that haze. And then early this week too, temperatures were expected to be 90 or higher Monday and Tuesday, and we just barely got to 90 in the Twin Cities both days. So came in a few degrees shorter than what we would have expected without the haze. And it's doing it again today. And I assume as long as the winds are blowing from a region that's burning, we will see some cooling effect on our air masses. But it's not going to make it feel cool once the heat kind of kicks back in. It'll just cool it down a little from what it could have been if there hadn't been any haze or smoke present.
Jim du Bois 02:23
Well, let's talk about how dry it is, and we have another drought monitor update coming tomorrow, Thursday, July 22. But if anything, it's just going to get worse than the last drought outlook, isn't it?
Kenny Blumenfeld 02:38
Yeah, I mean, you know, we did have a little bit of precipitation in parts of Minnesota last week. But the big story is Minnesota is not getting enough precipitation. You need at least an inch a week right now. You know, from now, right through August, you need an inch a week to keep pace, and we're not anywhere near that. Much of Minnesota is five inches short of precipitation just since the beginning of June. So, I think until we flip and start really getting precipitation in a widespread fashion, I would expect the drought conditions to continue expanding and degrading. That's kind of the term we use in the drought world, you know, where you basically move to worse categories of drought. So in my day job, I talked to the media a lot about, you know, current climate conditions or pervasive trends in our climate. And we've started to get questions about well, why, why has the posture changed? At the beginning of the summer, people were saying that it's not that significant of a drought, and now we're talking about it as a major drought. So it's kind of two points here, Jim. One is it is a major drought. At this point, there's no denying it. We have widespread impacts across Minnesota, everybody, I mean in pretty much every sector is feeling the effects of not having enough water available. Whether you're a farmer, and even we've seen instances of farmers that use irrigation still having crop stress because there's, there's really, they're not even enough moisture available from some of that groundwater that they're using. So, it is a major drought, but it's also an evolving and changing situation so early in the summer, even when we were talking about it a few weeks ago on this podcast, you know, we didn't know where we were going. But at that point, it was just dry. The impacts were starting to show up but they weren't really widespread. Well, now we're in what what many call the acceleration phase, right? This is a very hot time of year climatologically. The sun is still fairly bright. It's not quite as bright as it was a month ago in June. But this is where you would normally see drought really taking off, and our drought has really started taking off in the last couple of weeks. And I would imagine, you know, I can't game the system, and I don't have a crystal ball, but if we don't start getting meaningful precipitation, I would imagine that we're just gonna see the conditions deteriorate further through the summer. And I can't tell you, Jim, if this is going to be a historic drought that everybody talks about, but I think it's already become the kind of drought that you know, people who maybe are early in their careers, they're gonna remember this one, and kind of compare the next one to this. I think people with longer careers or who have been around longer as residents, you know, still recognize that 1988 was a much more severe drought than this one so far, but we don't know where this one is going. And it seems to have elbowed out the other couple of recent droughts from 2012, and even 2007. So, again, it's not yet as severe as 1988. But it is no joke. This is a major drought. We're seeing really low stream levels, lake levels, the moisture in the soils just been nose diving across Minnesota. And you got to go pretty deep, you got to go a couple feet down, and there you've still got some reservoirs of moisture leftover from the really wet period, you know, a few years back, but the topsoil in particular, quite dry. And, you know, we're seeing ponds drying up. Brown grass is everywhere, trees drying up, so it's just dry. And yeah, it's just a dry summer.
Jim du Bois 06:37
Well, and the drought isn't limited just to Minnesota, it really encompasses a large portion of the western United States and the southwestern United States. And you mentioned, of course, the haze holding down the temperatures which is the result of fires that are burning. And in Oregon, I'm sure a lot of folks have heard about the Bootleg fire. That fire is so massive, it is encompassing an area that is actually greater than the area of the city of New York. And the impact of this fire is such that it's actually creating its own weather. There's talk of pyrocumulonimbus clouds forming. What exactly are those, and how can a fire actually create weather?
Kenny Blumenfeld 07:27
Yeah, I mean, this is, this is the thing. I mean, we do see this occasionally. It's not that unusual. But some of these fires have gotten really enormous. And they're being fueled by themselves at this point. And then they create their own weather, as you say, and you can actually search for Bootleg fire and you're gonna get lots and lots of analyses and resources about it. You'll even see a little map come up. It's in basically southwestern Oregon. And it's by no means the only fire, either, it just deserves its own attention because, well, you just said larger than New York City, that is a very big fire. And this thing is roaring. So, a pyrocumulus cloud is kind of what it sounds like. It's a cloud a cumuliformer, heapy, billowy cloud that's made out of smoke from large fires. You can actually picture this because whenever you, you know, you're driving down the road and you see someone's bonfire or you see a fire that's gotten a little out of hand, you see what looks to be like a big cloud of smoke forming. Well, with a large wildfire forest fire, that heat is so enormous that you get these billowing plumes that go up 15, 20, 25,000 feet, and they actually become their own kind of cloud with updrafts and downdrafts. And they tend to be very dry. And so when cool air at the top of those clouds starts to descend, it can cause the cloud to collapse. And then this descending and very dry wind gusts out from the middle of this cloud and just fans the flames even further and kind of produces a fire front, essentially, that just sort of moves like a, kind of like a bow wave out ahead of a boat, out ahead of the fire and ignites new fire, and you see all kinds of strange behaviors. But we've also seen on some days and with other fires, including some that have been in Minnesota in other years, where the pyrocumulus cloud becomes big enough that it forms an anvil top, produces a little bit of precipitation and produces static discharge in the form of lightning and thunder. And then it becomes a pyrocumulonimbus, or basically a fire-generated thunderstorm. And it doesn't stop there, Jim. You've probably heard of these fire whirls, these little...
Jim du Bois 09:51
Yes.
Kenny Blumenfeld 09:52
...they're kind of tornado-like or waterspout-like whirls that form in some of these really intense fires. And some of these, in some instances, when the thunderstorm or the pyrocumulonimbus cloud gets big enough and mature enough, it can actually produce a legitimate fire bred tornado, which is, I mean, I like tornadoes and extreme weather. But I remember as a kid having a nightmare that there was a tornado made out of fire, and I never forgot it. And the fact that these things actually happened is somewhat terrifying. So, you get kind of a supercell thunderstorm forming out of fire, and it produces a supercell-like tornado. Woo, yeah, so the Bootleg fire is massive. And because there's no precipitation falling in this area, I mean, it is the dry season in Oregon, and so we wouldn't really expect much precipitation this time of year. So there's nothing to put the fire out. And as it gets bigger, and it produces these cloud and weather systems, it's just going to keep breeding more fire. So it grows and kind of fits and starts, and sometimes explosively with these, you know, outward gusts of wind that exceed 40 or 50 miles an hour and just fanning the flames all over the place. So yeah, quite an event up there.
Jim du Bois 11:18
Well, you mentioned, Kenny, that these pyrocumulonimbus clouds can generate what is essentially a fire tornado that actually was documented in Wisconsin back on the eighth of October, in 1871 in Peshtigo, Wisconsin. There was a large fire, and residents of the area reported seeing a fire tornado, and this was a very deadly fire. The death toll varies. Apparently, the records weren't kept very well back then. And I've heard anything from several 100 to over 1000 people perished in that blaze. So, I mean, fires, these are just amazing, the impact they can have on the weather as well. And and, you know, bring in these things that are the stuff of our nightmares.
Kenny Blumenfeld 12:07
Yeah. And, you know, I think that we all kind of started waking up to the terror of fire in the last decade, when the footage started coming in from McMurray up in Canada. And from some of these towns that were just, you know, people trying to escape that were fleeing for their lives, as fire was engulfing towns. And now of course, we've seen more footage out of California in the last few years. And then what we have here, and what we had earlier this summer, in British Columbia. And now here we are in Oregon. Yeah, I mean, fire is an incredible mechanism once it gets big enough. And it is, it can be, you know, pretty unnerving and terrifying to see. And, you know, you mentioned the Peshtigo fire. And you know, we here in Minnesota, in the early 20th Century, we had the Cloquet and the Hinckley fires. And you know, some of it has to do with land management. But when you get into really dry conditions, it doesn't have to be a heatwave, if it's just too dry, and there's not enough water in the vegetation, and you have a lot of downed vegetation or fallen vegetation for whatever reason, you start developing a really good checklists for building some nasty fires. So, one of my concerns, and I'm, you know, certainly not trying to scare anybody, but you know, the DNR and the US Forest Service have been fighting fires pretty heavily all year. And you know, our main fire season is in the spring, and then again in the fall, but there's still fires burning in parts of northern Minnesota, northeastern Minnesota right now. So even though it's not really the wildfire, forest fire season, it's been so dry, and there's enough fuel, that the fires are going even through what's normally our wet season. So I am a little concerned that as we get into September, if we don't see meaningful precipitation across a wide area, then we would have, you know, as the relative humidities drop naturally during fall, you know, we could have an explosive fire season if the climate doesn't get some things under control here. So you know, nothing, nothing to alarm anyone about but just not something that we would like to see because it has been very dry, and we really would like to come out of it.
Jim du Bois 14:23
Well, we're recording this on Wednesday, July 21. And in the days ahead, it looks like the temperatures are going to move back into the 90s again in a good portion of Minnesota. And this heatwave. Kenny, is there a heat dome involved with what we're going to be seeing here very shortly?
Kenny Blumenfeld 14:42
Yeah, that's a good question, Jim. So, I think you mentioned the heat dome because this has been a popular, popular term in the last few months, and a lot of times I kind of play a curmudgeon, it's like ah, this popular term, ah you're gonna have to clear things up. This one actually makes a good deal of sense. It's not a technical term. And I'm not sure what people picture, but I'll just put it real simply, is that hot air, warm air generally expands. And so, if you just take a given volume of air and you add a bunch of heat to it, that volume of air will grow. And the heat, the heat would sort of force the same mass of air to expand. And so, when you get a big hot air mass in place, the core of that air mass tends to be rather tall. And then as you move away from the core of the hot air mass, the height of that air mass starts to kind of shrink, or the thickness of it. So, if you were to look at it from the side, which would be super hard to do, but or if you could kind of color the temperature contours, you'd actually see a very subtle, wouldn't be steep, but you'd see a very subtle kind of dome shape, with the highest part of the dome corresponding roughly to where the highest temperatures are, on average, through that part of the atmosphere. So in that sense, anytime you have a good warm air mass moving in place, you kind of do have a heat dome. It's just that the one that we had in June was so well defined and had these very firm edges, it actually resembled a dome more than just about anything that we've seen in recent memory, for sure. So yes, there will be a heat dome associated with this hot air mass, it does look like it's going to be centered in the Dakotas. That's not great for them. But it's, I guess, merciful for Minnesotans. However, you know, this is basically an offshoot of the same mechanisms that have been driving the drought conditions for the entire western half of the US. It's the same mechanism that kind of ties our drought to the Western drought, and similar mechanisms that caused some of the extremes of heat in June in the Pacific Northwest. You know, even more recently in Montana, where temperatures rose into the 100 and low 100 teens. So yeah, I think that we're in for some really hot air, especially out to our west. But the one thing that kind of gives me a little pause is I wonder if we're ever going to really lose the smoky, milky veneer on the sky. And that might keep our temperatures from getting really out of hand. But you know, at least saving us from a couple extra degrees of heating. But yeah, it does look like a very hot air mass moving in, especially Thursday in western Minnesota, Friday over much of the state and then really into the weekend. And I would not be surprised if in many areas, the values that we record, top what we had observed during the June heat wave here, we might see some triple digit temperatures, possibly close to if not in the Twin Cities. I think it's more likely to see temperatures of 100 or higher out in parts of western Minnesota. But I wouldn't be surprised if Friday and maybe even into the weekend we have these really high temperatures. So Jim, I gotta ask you, you're a heat guy. You Like It Hot. But is there, is there a point, and I'm being serious, is there a point where kind of enough is enough and you'd like...I mean, are you are you kind of just eating this up? This is the summer of glory for Jim du Bois.
Jim du Bois 18:34
Kenny, that's an excellent question. And as much as I love the heat, I have to say that I'm starting to tire of it a little bit. Not so much because of the heat itself. But all the other things it brings. If we had heat punctuated with some nice rainfall, that would be great. If we had heat minus wildfires that are creating air quality alerts, I would much prefer that. So no, I I'm really kind of, I guess, less than enthusiastic now, just because I'm seeing the downside of all of the hot weather we've had so far this summer.
Kenny Blumenfeld 19:10
Yeah, that makes sense, too. I mean, it's drying everything out, too. So you know, if you have a lawn or garden, it's making you work harder to maintain it. And at some point there's going to be restrictions where you're probably not supposed to do that anymore. So...
Jim du Bois 19:24
Well, they're already here.
Kenny Blumenfeld 19:26
Yeah, OK.
Jim du Bois 19:26
Got the city of Minneapolis, St. Paul, I believe New Hope, Golden Valley and some other cities have watering restrictions right now. So we're we're at that point. And what's amazing is here in Minneapolis, we actually get our water from the Mississippi River, and it used to be the cities that would be the most impacted by dry conditions would be those that depended upon wells for their water supply. But the level of the Mississippi right now I believe may be approaching some record lows if I'm not mistaken.
Kenny Blumenfeld 19:57
It's, it's not quite at the historical benchmarks, but it's dropping below some critical values up at the Anoka guage site. It is low. I mean, you know, you don't want it below what is it, 1500 cubic feet per second? And I think it's dipped below that threshold already. And then maybe it might have recovered a little bit. But yeah, you start getting into record territory when that drops below about 1000 CFS, cubic feet per second. Yeah, here in St. Paul...so I live in St. Paul, and we agreed that we wouldn't water at all beginning in May. It just seemed dry, and it seemed pointless. And we were...figured we'd save water for other purposes. And we're kind of transitioning our lawn anyway, so it wouldn't be a priority use to take water that could be used elsewhere for other purposes for us. So, we've had our own kind of self-implemented watering ban all summer. But it is a, it's kind of hot and dry time. So the other thing that is probably worth pointing out is the heat. Heat has been a little bit hard to forecast the last couple of weeks because there's been these different forces. So you've had on one hand this big ridge or dome, kind of heat dome or ridge of high pressure out west. And when it has lurched into the region, we've gotten really hot. We've also had this kind of almost semi-permanent low pressure area off to the east and northeast that's been providing these bouts of much cooler air, even into Wisconsin and Minnesota. Did you notice, I think it was last week, some of those really cool nights? You wake up and as in the 50s in the morning...
Jim du Bois 21:39
Oh, very pleasant. Yes. Great sleeping weather.
Kenny Blumenfeld 21:42
Yeah, kind of marvelous. And it was almost like in this summer of smoke and hot mayhem, where did that come from? And you know, parts of Wisconsin that have not, especially if you go in in the northeastern part of the state, they're kind of wondering what we're talking about because they they've had adequate moisture and precipitation, and it's been relatively cool, most of the time. So, it has been difficult to forecast the high temperatures, especially over Minnesota, which is kind of in this transition area between the very persistent and extreme heat out west, and the much cooler conditions off to the east. It does look like though, I mean, we've seen this now on all of the models that, you know, there might be these little breaks in here for a day or two, kind of like we're having today as we're recording, it's not super hot. But everything that we've seen suggests that the majority of the next two weeks will be warmer than normal, possibly hot. And you know, some of the longer range models that we use to kind of help us see out a week or more, they're indicating that the heat is going to hold on right through the end of the month and into August. So you know, again, with some breaks possible, but the bottom line is there isn't any, anything that's emerged come over the horizon yet that tells us this is all about to change. And we could be bracing now for the hottest period of summer so far.
Jim du Bois 23:11
Well, Kenny, we're seeing the dew point now starting to creep up a bit, and that will happen over the next few days. Does that bring any hope at all for any relief in the form of precipitation?
Kenny Blumenfeld 23:22
Yeah, that's a good and optimistic question. And I think that, um, you know, one of the one of the things, Jim, we've now heard from a lot of people in agriculture, and I think we get it, I think that the picture is that crops are stressed across the state. Plants and gardens are stressed across the state. Lawns, of course, are stressed across the state. But there are pockets of even central Minnesota, and definitely parts of southern Minnesota, where there have been at least occasional beneficial rains. And you can see some difference where you can see some improvement where it's, you know, kind of apparent that things have fared at least a little bit better, or maybe they even look almost normal. But as we get more humid, we could hope that more of these precipitation events will affect more of the state. I don't see a real clear signal of anything widespread. But what I'm hoping for is that as we start to heat up, you get enough heat to drive, you know, individual isolated thunderstorms that then, you know, hit at least some small proportion of the area and drop a decent amount of precipitation. So, I think it would just kind of enhance or at least continue the kind of pattern that we're seeing where there's kind of drought and dryness-related problems visible pretty much everywhere. But you do see these small pockets where there's been at least almost enough precipitation in these very small pockets where things are doing okay. And I'm kind of thinking that that's going to continue. So through the heatwave, I wouldn't be surprised if we have thunderstorms in and around the state of Minnesota somewhere on most days, but on any given day, these thunderstorms or showers occupy, you know, only between one and 5% of the state and generally aren't providing more than a quarter to a half an inch in most of those places, and maybe some isolated amounts higher. So, kind of mixed news on that front. Like I do think there will be some thunderstorms and some, some much needed rains. But I think they're going to be very isolated and, you know, confined to relatively small areas until we get a, you know, a major weather system coming through that can actually produce widespread precipitation. Let's hope.
Jim du Bois 25:50
Well, fingers crossed on that, Kenny. And yes, over the next few days, if you suffer from any respiratory issues, you should be very, very cognizant of the fact that the air quality is not good. Also, as the temperatures and the dew point start to creep up, make sure you're well hydrated. Stay out of direct sunlight. Just take care of yourself, and listen to your body.
Kenny Blumenfeld 26:15
Yeah, good, good reminders, Jim, for sure, because it's a, it's not going to be a real easy time. And I think that the, you know, I'm not a, I'm certainly not a psychologist or social worker. But my hunch, just based on some of the conversations that I've had, is that these tough weather conditions are also sort of taking a toll on people mentally. So going into a heatwave that feels almost unrelenting could produce some additional stress. I'm sure.
Jim du Bois 26:45
Exactly, and not that the last 16,17 months or so haven't been pretty tough for other reasons. So...
Kenny Blumenfeld 26:52
Yeah, that is true, Jim.
Jim du Bois 26:53
It's kind of pouring it on right now with the uh...
Kenny Blumenfeld 26:58
Yeah, so you're saying that this wild weather isn't happening in a vacuum.
Jim du Bois 27:03
Exactly. Exactly. Well, everyone stay safe. Kenny, as always, great chatting with you. And we'll check in with you again in about a week.
Kenny Blumenfeld 27:12
Very good. Yeah. Good talking with you too. And hopefully we'll have some better news coming soon. But we are in a drought, and you should not expect big changes in something slow moving like a drought.
Jim du Bois 27:24
This is Way Over Our Heads. It's a weather and climate podcast. I'm Jim du Bois. Kenny Blumenfeld's a climatologist. We'll catch you next time.