Tracking severe weather, continued heat and humidity

[MUSIC PLAYING] CATHY WURZER: It's going to be an oppressively hot and sticky day today with highs, as I mentioned, in the mid 80s and lower 90s. There is a chance for severe weather bubbling up because of the volatile atmospheric conditions. Our chief meteorologist Paul Huttner is tracking all of it for us. He joins us right now. Hey, thanks. How is it going today? It looks like it's going to be busy for you.

PAUL HUTTNER: It is. It's a watched pot, Cathy. In fact, storms are already firing in Eastern South Dakota. There is a severe thunderstorm warning that includes that far western little bump out in Minnesota, Traverse and Big Stone counties, the Wheaton area, Beardsley, Ortonville. That severe thunderstorm looks pretty gnarly coming out of eastern South Dakota. It's not in Minnesota quite yet.

But that's the area we're watching and that NOAA's watching. They are now saying, just sent out an 80% chance that they will issue a severe weather watch, including that area in western Minnesota here very shortly as those storms continue to move in and intensify.

Cathy, the heat and the humidity today, you've been talking about it, the dew points are in the upper 70s. 79 in Madison, Fergus Falls, parts of southwest Minnesota, that is just rocket fuel, tropical humidity. Combine that with the heat, most of us will hit 90 today, and that's just perfect conditions for severe weather here across western and southern Minnesota today.

CATHY WURZER: OK. So what are the main risk factors? High winds, hail?

PAUL HUTTNER: Yes. Large hail.

CATHY WURZER: OK.

PAUL HUTTNER: Yes, large hail. The updrafts with these storms will be consistent and strong. So we could get 2-inch hail stones way up in the clouds that could fall to Earth.

And then it looks like this will form an MCS, one of these Mesoscale Convective Systems. That's a big, organized cluster of thunderstorms that could pick up steam and then move into Minnesota, maybe race east across Minnesota, 70 to 80 plus mile an hour winds with that, Cathy. This could be knocking down trees in areas where it gets going and gets some momentum.

NOAA's saying that they've upped it to an enhanced risk now, Mankato, Willmar, west of the Twin Cities in southwest Minnesota, and bumped the Twin Cities up to a slight risk. So basically, they're saying the severe risk is increasing in Minnesota. This could be a very rough afternoon and evening.

And as far as the timing, it looks like the storms will be into western Minnesota now early this afternoon and just gradually, slowly work their way across the state. Most of the models, Cathy, are trying to keep the storms out of the Twin Cities until this evening, until maybe around dark or after dark, 9, 10, 11 o'clock tonight. We'll see, that storm complex already crossing the border now, if it gets here any sooner. So it's just going to be an hour to hour, watching the radars now this afternoon.

CATHY WURZER: Do you see that maybe these storms could lose some steam as they come closer to the Twin Cities, based upon the time of the day?

PAUL HUTTNER: Yes. Time of day and also the severe weather parameters that we look at are stronger in western Minnesota, and then they start to fall off a little bit as you get into the Twin Cities. So most of the forecast models are saying they could lose a little steam this evening.

But these things can sometimes have a life of their own, Cathy. And they're feeding off these dew points in the 70s. So there's plenty of moisture. We'll see if this thing gets going. It could potentially still be severe when it gets to the Twin Cities and eastern Minnesota this evening. But it may be weakening just a little bit as it approaches.

CATHY WURZER: OK. Say once it blows through, what's behind this?

PAUL HUTTNER: Yeah, maybe just a slight chance of a thunderstorm tomorrow, but a sunnier sky as we head into Friday and Saturday, good-looking forecast. Still 88 to 90 degrees, still a little bit humid. Sunday, we'll get a front come through could bring a slight chance of thunderstorms, but some cooler and less humid air, Cathy.

Dew points could drop into the 40s up north and maybe 50s here in the Twin cities, 82 for the high Sunday. So it looks like a much, much more comfortable day as we head into Sunday.

CATHY WURZER: Good news. Do you believe it's going to be August 1 tomorrow? Oh, my gosh. And of course, you know, we talk about the dog days of summer. Are we in that the dog days right now?

PAUL HUTTNER: Yeah, we're right in the middle of them. By the way, yesterday we did tickle 90 in the Twin Cities. So that was Day 3 of 90 degree heat this year. Today should be Day 4.

13 is the average. I don't know if we'll get there this year, but we have a shot. And you're right about the dog days. We're right in the middle of it.

This goes back to ancient Roman times, Cathy, thousands of years ago. They called this period from July 3 to August 11 the dog days of summer, 20 days before and after the dog star Sirius rises with the sun in the eastern sky.

So they thought that added a little extra heat to the atmosphere this time of the year. Of course, it's just the sun and the lag of seasons that causes this to be the hottest part of the year, but interesting stuff from the ancient Romans. And we are indeed in the dog days.

CATHY WURZER: I didn't know the origin. Thank you so much. So I know we've got Climate Cast coming up. You want to give us a preview?

PAUL HUTTNER: Yeah, we do. You know, remember those old campy '50s sci-fi movies where scientists were the heroes? Well, not so much anymore, especially when it comes to climate denialism. I kind of wondered how did we get here.

And I'm going to interview David Luepke. He's a New York Times best-selling author. He's got a new book about climate denialism. So we're going to talk about the origins of that and where we stand today with regard to climate opinion around the United States and the world.

CATHY WURZER: OK. That's Climate Cast, coming up later this week. Say, just for folks tuning in, maybe a little bit late in our conversation, just give them a once over here in terms of what they have to be thinking about here this afternoon.

PAUL HUTTNER: Yeah, so already severe thunderstorms just approaching the western border with Minnesota now, Bigstone, Traverse County. Cathy, this line of storms will intensify and move east as it goes through the day.

So western Minnesota, looks like you're going to get a severe weather watch any minute here. Eastern Minnesota, Twin Cities, probably more like evening in terms of arrival for thunderstorms. So just keep an eye out today, Cathy. We'll probably see those watches expand eastward into eastern Minnesota and the Twin Cities late this afternoon.

CATHY WURZER: OK. So I know you're going to keep an eye on this. Thank you much.

PAUL HUTTNER: My pleasure. Thanks, Cathy.

CATHY WURZER: This is MPR's chief meteorologist, Paul Huttner, of course. You can listen to him this afternoon with Tom Grennan on All Things Considered. You can also sign up for daily text alerts to get the forecast and any weather warnings on your phone. You can get the latest, by the way, on the Updraft blog at mprnews.org. We got you covered.