Warm weather Wednesday with smoky skies, cool front on the way

CATHY WURZER: Well, school, friends, as you all know, is back in session. Can you believe that? What happened to summer? I keep saying this, by the way. Meteorological summer technically ended on Saturday. And the weather, though, has been really quite lovely this week. However, we will start feeling those fall temperatures soon enough, very soon. NPR meteorologist Sven Sundgaard is back with a weather update. Hey, how are you doing?

SVEN SUNDGAARD: I'm doing pretty good. I have to just say, my makeup is on point right now. You can't see it. But--

[LAUGHTER]

CATHY WURZER: You always look sharp.

SVEN SUNDGAARD: Yeah. I'm late to the game on all those TikTok trends and stuff.

CATHY WURZER: Yeah, me too. Me too, yeah. Well, it's gorgeous, I have to say. I'm looking out the window here in downtown Saint Paul. But for our friends in Northwestern Minnesota, a little smoky, perhaps?

SVEN SUNDGAARD: Yeah, it's going to get that way. Right now, the air quality is really quite bad in much of North Dakota. It's in the purple or even the maroon category, which is as bad as it gets. You want the air quality index to be under 50. And it's 200 to 300 across parts of North Dakota. So this cold front that is going to bring the chill by the end of the week is pushing that smoke to the surface from Canadian wildfires.

So air quality alert does go into effect at 5:00 PM today through 11:00 AM tomorrow. That includes all of Northwestern Minnesota, Fergus Falls, Detroit Lakes, Bemidji, Moorhead, Roseau, some of those places. And for the rest of us, it will get into probably that moderate category as we head into tomorrow, not expecting it to get to the unhealthy category yet. But it's something we're going have to watch because, as I said, the air quality has really diminished through the day here in North Dakota.

CATHY WURZER: Wow, I don't think I've ever seen purple or maroon when it comes to air quality.

SVEN SUNDGAARD: We did have some in Minnesota last summer. Maybe you blocked it out because it was a bit traumatic. And also, New York, Chicago, remember some of the video and photos from last summer?

CATHY WURZER: Yeah, good point, good point. Thank you. I'm wondering about, looking at the summer that has just passed, so we ended up normal? Is that right?

SVEN SUNDGAARD: We ended up almost perfectly average, just a couple tenths of a degree below normal. Parts of Northern Minnesota were slightly above normal. And what's really startling about that, Cathy, is this was the coolest summer in nine years in the Twin Cities. And it ended up barely below average. Statewide, it'll end up being the coolest in five or seven years, depending upon the final numbers. It's going to be that close. And, yeah, what's startling about that is, we've just consistently been above normal.

And, of course, normal is using the modern average. 1991 to 2020, that's what we use for normal now, which is two degrees warmer than the summer climate would have been a century ago. So everybody was above normal if you compare it to 100 years ago. Of course, the big story, though, of the summer was the rainfall. Parts of South Central Minnesota saw double the normal rainfall. Places around Faribault had almost a whole year's worth of rain, over 25 inches of rain, Twin Cities, officially, 1 and 1/2 times normal. But there were parts of the metro that saw pretty close to that double normal rainfall amount, too.

CATHY WURZER: I tell you, the Faribault numbers, I still can't get my head wrapped around that. That's amazing.

SVEN SUNDGAARD: Yeah, in a three-month period. We average about 31 inches of rain in a year. And some spots saw 25 to 27 inches, just June, July, August.

CATHY WURZER: Wowzers. OK, so it looks like we have a relatively warm-ish day here today.

SVEN SUNDGAARD: Yeah, we're in the upper 70s now. We're seeing some 80s out across Western Minnesota, 80 right now in Marshall. But that cool front is already pushing into Northwestern Minnesota. Thief River Falls right now, 68. The wind has switched out of the Northwest up in Hallock. So that's where the front is right now. And there's even some showers up there, just plain old rain showers right now up around Fosston, Red Lake, over towards Baudette that is ahead of that cool front.

So it's going to stay dry during the day for most of us in Central, Southern, Northeastern Minnesota ahead of that front, low 80s, probably, for most of us in Southern Minnesota, warmest day of this week. But that front is going to dive south overnight. And that's going to create a pretty wide area of scattered showers and thunderstorms. This is not going to be an all night rain. This is not going to be a heavy rainfall event.

But there will be these spotty showers and thunderstorms. And the storm prediction center is hanging on to this marginal risk level, one out of five, of severe weather. They kind of narrowed it now to about Pipestone through the Twin Cities, St. Cloud, Brainerd, Duluth, the North Shore. And I want to stress, this is not going to be a repeat of last week. But we could see one or two storms that prompt a severe thunderstorm warning briefly in the late evening overnight hours.

The main threats would be maybe a brief damaging wind gust or maybe some of that borderline one-inch hail. And most of us are going to see well under a half inch or even a quarter inch of rainfall. Best chances of seeing some of the more substantial rainfall amounts around a half inch will probably be the high range into the Arrowhead.

CATHY WURZER: OK, thanks for the heads up. So what about the rest of the week?

SVEN SUNDGAARD: Yeah, behind the front, the cool weather is coming in. Tomorrow won't be real cool just yet, still 70s in Southern Minnesota, 60s to the North. We'll have some lingering showers, some clouds to start, but decreasing clouds through the day. But Friday, Saturday, that's when you're really going to notice the difference, reinforcing shot of cold air, 50s only for highs on the high range Friday afternoon, 60s in southern Minnesota.

And that's going to set us up for the coldest night since May for most of us-- widespread 30s across northern Minnesota. I think places like Hibbing are probably going to have their first frost. June 10 was the last time they hit the 32-degree mark. Twin Cities below 50, we haven't done that since May 25. So it will get your attention early Saturday morning.

But really a gorgeous weekend. Sunshine both Saturday and Sunday. Still cool Saturday, but back in the 70s for most of the state Sunday. And we're not done with summer. We know September can yield some nice days. It looks like most of next week, above normal temperatures, low 80s for southern Minnesota, 70s to the north. Climate Prediction Center calling for a high likelihood of above normal temperatures next week. But we know where the trend is going.

CATHY WURZER: Good, OK. At least we're not going to completely kiss summer off. Thank you.

SVEN SUNDGAARD: No, not yet. You're welcome.

CATHY WURZER: Have a good day. That's Sven Sundgaard.