Alaska’s winter off to slow start with late freeze-up and above normal temperatures

Winter’s arrival has been a bit delayed in much of Alaska, as warmer-than-usual temperatures persist and any snow that’s lasted more than a day is either at higher elevations or latitudes.

Take Fairbanks, for example, which had its latest freeze-up on record, in about 125 years of record keeping.

National Weather Service climate researcher Brian Brettschneider — back for our Ask a Climatologist segment — says, as far as predictions for the rest of winter, we can bet on Alaska temperatures being warmer and for the cold season to continue shrinking.

Listen:

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This interview has been lightly edited for length and clarity.

Brian Brettschneider: Well, at Anchorage International Airport, they had a their first freeze of the season on Oct. 3. It dropped to 31 degrees, and that is six days later than normal. Now, looking at what’s happened over the last 10, 12 years, you know, I think about four times by now we’ve already had snow, and some decent snow in some cases, by this point in the season. So it feels like we’re kind of slowly progressing through fall, but in past years, we’ve already started some of our winter activities by this point.

Casey Grove: And I guess as far as freezing conditions happening, that is a similar story in Fairbanks, too, right?

BB: Even more extreme in Fairbanks. So Fairbanks had their first freeze on Sept. 28, and that is the latest on record. And they’ve been keeping records in Fairbanks for about 125 years. So latest freeze any year on record. It only broke the record by one day, but it’s late by three weeks. Now, if you’re in the Lower 48, three weeks late, you know, it’s pretty late. But given how fast temperatures typically drop in Interior Alaska, I mean, three weeks is an eternity, so it’s really quite notable.

CG: Well, safe to say winter is coming, right? I guess more broadly, you know, as you look at the seasonal outlook, what do we think is going to happen? At least, what does NOAA think is going to happen?

BB: Well, we have a few tools that we have at our disposal to kind of estimate what future conditions are going to be like. And the first and foremost is the Earth is warming. And if you know nothing else about the climate system, you should probably predict that it’s going to be warmer than normal. That’s a pretty safe bet, too, all other things being equal.

After that, it’s really the state of the tropical Pacific. So El Niño, La Niña, that’s our next best indicator for what the upcoming season is going to be like, and we are dipping into a La Niña for the fourth time in five years. We’re not quite there yet, but we’re progressing toward that. And when we have La Niña conditions in Alaska, it’s pretty reliably cooler than normal. When I say cooler than normal, normal is a lot warmer than it used to be. So you know, a La Niña in the mid-2020s is probably going to be warmer than, you know, an El Niño from 50 years ago. But compared to recent years, more times than not we would expect it to be cooler than normal.

CG: You said for the fourth time in five years. So last year was an El Niño, but we still had a pretty solid snow winter. Here in Anchorage, it was the second most of all time, right?

BB: Well, yes. We need to think about temperatures and snow or precipitation independent of one another, right? So we had a really significant cold outbreak for about a week at the end of January and beginning of February. Other than that, it was a pretty nondescript winter, temperature-wise. And as far as snowfall, most places were snowier than normal, which is typical of an El Niño year, or wetter than normal. It was more so in Anchorage. Anchorage has kind of been right at the center of a bullseye for a couple of years in a row, not very representative of large areas, but last year was unusual.

So going into last year, you know, the safe bet was it was going to be warm with not a lot of snow, and it was the exact opposite of that. So these seasonal outlooks, they provide some guidance of kind of which way it might go, but it’s not a prediction, if you will. So it might be right, you know, 60, 65% of the time, but that means it’s wrong a third of the time. And those third of the years, you know, everyone kind of hunts me down and said, “But you said it was going to be this,” but, you know, a third of the years is not nothing. It’s a lot, actually.

CG: Yeah, no doubt. And like you said, I mean, it’s not a prediction, it’s a sort of a general vibe or something, right?

BB: Something close to that. It’s a thumb on the scale. But, you know, sometimes you eat a couple pieces of birthday cake and you still lost weight at the end of the end of the week, right? So, you know, sometimes it doesn’t work out like you think it’s going to.

CG: I’m going to use that one on my wife, I think. You know, “Just because I ate two pieces of cake, lady.” Well, maybe let’s talk some more about snow. I mean, is there much that we can even kind of guess at this point about what sort of a snow winter we’ll have this year?

BB: So in a La Niña winter, typically it’s wetter than normal in the Interior for most of the mainland, say north of the Alaska Range, and it’s typically a little drier than normal for the southern mainland.

CG: And when you say “wetter,” is that just any kind of precipitation?

BB: Any kind of precipitation.

CG: Gotcha.

BB: You know, from a climate point of view, we really don’t distinguish between rain and snow. We just think about it in terms of precipitation. Now, in the season, that’s a big distinction. So it’s actually common for La Niña winters in the southern mainland to be drier than normal, but also kind of snowier than normal, because what we do is we we tend to have less winter rain, and when it does snow, it’s typically a little bit fluffier snow, so it piles up more. So we kind of negate that decrease in precipitation with some other factors that tend to favor more snowfall.