This winter in Alaska was one full of notable superlatives, especially for the state's main population centers.
Statewide, Alaska saw its coldest December-through-March in a half-century. In famously cold Fairbanks, that same period was the coldest on record. Juneau had its coldest December ever recorded and — in a place known for being snowy — its snowiest winter. And, while not as extreme, Anchorage saw its coldest-ever month of March.
In the shift to spring, the melt is on across the state, but a bigger shift is coming, as forecasts indicate an El Niño climate pattern is on its way.
That's according to National Weather Service climate researcher Brian Brettschneider, back for another Ask a Climatologist segment. For now, as Brettschneider told Alaska Public Media's Casey Grove, he wants to linger on the chill of the winter gone by.
This interview has been lightly edited for length and clarity.
Brian Brettschneider: This is really the winter the old timers would talk about. So from the mid 1970s and earlier this was a typical winter. This is what it used to be like. So we got that taste of the kind of the old school winter that the old timers and the elders would talk about.
Casey Grove: As somebody who was born and raised in Fairbanks, maybe we could start there, in a place that is just really known for cold. What the heck happened? Like, how? How did that happen?
BB: Well, it takes a confluence of events to keep us in the deep freeze for a long time, and that's really what happened. We were in a very persistent pattern.
So it's not uncommon, even in a warm winter, for there to be kind of some transient cold spells. And the way you get that is kind of mid-level high pressure over eastern Siberia and low pressure over central Canada. And between those two, you get a good northerly flow and clear skies, which enable cooling because there's almost no solar energy.
That wasn't a weeklong event this winter. That was a multiple-months-long event. And so it was just relentless. It never ended.
CG: Juneau, also known for being a pretty snowy place, like you said, snowiest December on record, and snowiest March. Let's get into that. How did that happen, and what were some of the numbers there?
BB: So it's interesting that in 2007, we were very cold in the mainland, and Juneau had their snowiest March on record. Well, this March, we had the exact same pattern, and Juneau had, again, their snowiest March on record.
Just the way that that the flow that was northerly over the state, it took an eastward turn over the central Gulf of Alaska and then moved straight inland. And that really enabled low pressures to spin up there and then to tap into moisture from the subtropics. And it was just one after another.
They had a record number of days at one point with 1 inch of snow, I think, 10 days in a row. Then they had another period where they, two weeks later, where they had 2 inches of snow every day for, I believe, eight days in a row, which is a record for Juneau. It all works together. The same reason it was cold over the mainland is the reason it was snowy over Southeast.
CG: So how did things shape up in Anchorage here? Obviously not as cold as Fairbanks, not as snowy as Juneau, but a ton of people live in this region. And how did things shape up here for the winter?
BB: Yeah, it was a cold winter, for sure, in Anchorage. And what's interesting is, if you look at which month was the coldest, it was actually March. March was our coldest month of the winter, and that hadn't happened since 1960-61 and usually that can only happen when, you know, kind of December, January and February are pretty warm. But all three of those were still colder than normal. It was really remarkably consistent, really, the entire winter.
CG: We're, you know, a little bit over a week into April now, and things have drastically changed, right? I mean, the trails are turning to mush, and that's an inevitable warmup. We see that every spring. We have spring breakup, the rivers are going to be going out in not too long.
But looking a little bit more long term, it sounds like we are headed for a major warm up, climatologically speaking with an El Niño, and I've heard this described as a "super El Niño." What's the story there? And what do you expect?
BB: So every month, the NOAA Climate Prediction Center updates their outlook for La Niña or El Niño, and the next outlook, it's pretty aggressive. It's going to call for a 50% chance of having a strong or very strong El Niño by the end of the year, and it's bumped up the timeframe.
Previously we thought maybe by June, July, August, we would kind of creep into that category, but now we're thinking a month before that — May, June, July — and all the probabilities have risen for how strong it's going to get. Now, some of the stories online use terms like "Godzilla" and "super" and, you know, there's kind of sensational headlines, and they're looking at the most extreme scenarios, which can always happen.
That's not currently the forecast, but the current forecast shows that it's going to be likely a strong El Niño, and for most of Alaska, that means warm. In the summer, it means about 1 to 3 degrees warmer than normal, and in the winter, it means about 2 to 4 degrees warmer than normal. And with the exception, maybe of the West Coast and the North Slope, which tend to be actually a little cooler in El Niño winters, the big thing is, it means way less snowfall. So El Niño winters are are not good winters if you like snow.
