Green-up season refers to the period when trees and vegetation begin to leaf out after winter dormancy, marking the transition from winter to spring. In Alaska, this phenomenon is scientifically monitored through consistent observation of specific landscapes, such as the Chena Ridge hillside in Fairbanks, where ecologists have been tracking green-up since the mid-1970s. Green-up is ecologically significant because it triggers evapotranspiration, where trees release water vapor into the atmosphere, increasing afternoon humidities and potentially influencing shower and thunderstorm development. The timing of green-up is primarily determined by accumulated spring warmth rather than winter temperatures, as trees require sustained warm conditions to activate sap flow and leaf development. A later green-up season, such as the one observed in 2026, is typically associated with cooler and wetter spring conditions, which can delay the start of wildfire season by keeping vegetation moist and reducing fire danger.
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Good afternoon. I'm meteorologist Bailey Brown and you might have noticed if you're in South Central a little bit more of that rain and that cloud cover.
Now, we're expecting even more of that into this work week, but for the interior you've had a lovely weekend.
Some cloudy skies at times, but you've had some of that sunlight and you've had warmer temperatures. Now, as we look ahead through this upcoming week, more cool temperatures are ahead for South Central and we're starting off the work week just a little bit wet in Southeast with a little bit more of that rain expected. Now, as we jump into our graphics for starting off with our sun data, sunset at 10:46 tonight, sunsetting at 11:17 in Fairbanks, 9:22 in Juneau and 11:30 in areas like Bethel. Now, I wanted to show you these temperatures currently right outside your window. Temperatures are starting to cool down for the night, so keep that in mind as you make any late in the day plans. Temperatures sitting in the mid-50s across the interior and slightly cooler down in the southern portions of the state. You can actually see that trend of temperatures sitting in the low to mid-40s from Adak all the way to Ketchikan. The southern coastline is staying on the slightly cooler side. So, for Anchorage I wanted to point out that so far this month of May we're halfway through it. We've only had 3 days either at or above our normal temperatures for this time of year. So, I guess that just indicates that more of these cooler temperatures are on the way and this spring so far has just been below normal in terms of these temperatures. May or March absolutely was below normal. That was when we had that cold snap. April sitting below normal with even more wet conditions than we typically see. And May, more of these cold temperatures. So, for tomorrow as we look ahead, just a quick glimpse in our forecast before we get into the more detailed uh areas, Anchorage, we'll see mostly cloudy skies. Now, that doesn't mean we won't see any of that sunshine. We will see some partly sunny skies at times, but otherwise throughout the day, we will see a lot of that cloud cover. High temperatures sitting in the low 50s, and that will continue all throughout this week. Meanwhile, into the interior, partly sunny skies are expected. The skies you had today and yesterday will continue into Monday with more temperatures sitting in the 60s. Now, for Southeast, more rain is heading your way. We will see it dry up as Tuesday approaches, but for areas like Bethel and Southwest Alaska, more scattered showers are expected with that next storm beginning to move in.
So, so far through the day today, we saw mostly cloudy skies. That low-lying level of moisture, and you could even see it right there, completely covering Sleeping Lady. And that is a stratus layer that we have. We even saw a little bit of those raindrops peaking through in Anchorage today as well. However, most of that rainfall was into coastal areas like Seward and even into the Copper River Basin. So, if you live in these areas, let me know how it's looking for you. I know Portage Glacier got nearly 3 in of rainfall today, and more is expected into tomorrow. Now, something that's kind of cool that I wanted to show you, we have that low pressure system, but check out where this front is. You can see it just a little bit more on the map if I zoom in.
It's all the way down stretching into Southeast. So, keep in mind where this band of white is right here, uh because I wanted to show you something kind of cool that goes in with this storm. We're seeing temperatures cooling trend or trending cooler in areas where you saw that frontal system pushing through. So, you can not only see it in our satellite, but you can also see it when we're tracking these temperatures, what's being left behind, where that next storm is starting to brew. We're seeing warmer temperatures compared to yesterday in Unalaska and Cold Bay. 11° cooler in Juneau today compared to yesterday. That is all due to that front moving in from the storm system, sweeping in a lot of that wet weather, and that's extending as far north as areas like Fairbanks, even out to the west in Gamble and Nome.
Now, today we did see a little bit of that heavier rainfall. We're still seeing some of that rainfall in areas like Copper River Basin and Yakutat.
That's where the heaviest amount of rain happened for Southeast, but in South Central, the heaviest amounts of rainfall occurred in Portage Glacier. Last time we measured it was about 30 minutes ago or so, and that measured out to be about 2.8 in of rain just from the last 24 hours. So, even more is on the way. That just indicates how much moisture that storm was holding.
But, we're going to take a look at our satellite and radar from today. We have this winter weather advisory, and it's spring. We shouldn't be seeing this, but we are. This is all due to some cooler temperatures that are starting to shift into areas like Diomede, the Bering Strait Coast, and St. Lawrence Island.
This is where temperatures are going to reach into the low 30s, even overnight lows dropping below that freezing point.
But, this is not only for some stronger winds, but the biggest concern is going to be up to about an inch of that snowfall. So, it's not really a whole lot of snow, but it's important to keep that in mind, especially since it's a complete shift from the spring-ish weather that we've seen in these areas.
There is also a potential for some ice accumulation, so keep that on your mind if you live in these areas.
But, another thing we'll be talking about today are these areas highlighted in green. These are our flood watch areas. This includes areas like Buckland, um Anvik, and even Galena and Ruby as well.
Kaltag's another area. That flood warning is still persisting into Galena.
Where you see this winter weather advisory, this is going to expire Monday morning with up to about an inch of snow like I mentioned. Areas like Galena, Ruby, Kaltag, that flood watch is going to expire by 10:00 p.m. tonight. But for Anvik, that is going to expire Monday evening. For Buckland, we're also seeing this flood watch expire tonight at 10:00 p.m. It's likely that this flood watch is going to be extended into tomorrow.
That's kind of how it's been the last couple of days with these flood watches, but it's still important to keep in mind. We also had that flood warning highlighted for Galena. That's still in effect and you should take caution if you are in these areas. There's been some low-lying flooding that has been reported. Um, and I'll go into more detail on that during our later newscast on the 10:00 p.m. show. And if you have any questions, please feel free, uh, to leave a comment or anything like that.
But into the interior, this winter, or this wind advisory has actually been, uh, compressed a little bit more from what was the entire Alaska Range now to just the eastern side of the Alaskan Range, or the Alaska Range. This red flag warning is still in effect through 10:00 p.m. tonight with winds up to 55 mph gusts. The big concern for the interior this week, not just for Delta Junction, but for the entire interior, is just dry conditions. You're not seeing any rain in the forecast anytime soon. If you do, they're going to be very spotty, very isolated, random showers. Uh, but otherwise, just still lots of that sunshine, but winds will carry anything that carry sparks or anything, um, that is likely to catch fire. That wind is definitely going to take advantage of that. So, keep this in mind, dry conditions and windy all throughout this week. That fire danger is very high across the interior.
Now, as we look ahead for this week, coastal areas like South Central and into Southeast can expect more of these showers through the night tonight and even into tomorrow. Kodiak has that next round of rain pushing in by tomorrow morning. Homer, Seward, Copper River Basin, these areas can expect more rain as well. You'll notice two small fronts associated with that next storm shifting in. Areas like Dillingham will see a mixture of that rain and snow. Snow is still a possibility in higher elevations, not just for Southwest Alaska, but also for um areas like South Central and Southeast. We'll see lots of that sunshine for areas like the interior, but scattered showers likely for Bethel and into Dillingham. Mostly dry and mostly cloudy for Anchorage and the Mat-Su Valley. Inland areas for South Central will stay mostly dry and mostly cloudy. And again, you might even see a little bit of that sun popping out throughout the day at times, but otherwise, it is going to be mostly clouds blocking the view of that sunlight. Now, for Southeast, you're taking a break from Monday afternoon into Tuesday morning, but you'll see a return in that wet weather by Tuesday afternoon. Today's precipitation over an inch and a half of rainfall in Yakutat, about 4/10 of an inch nearly into Juneau, and just much lighter amounts for the rest of the region. Not too far behind in areas like Sitka, expect a little bit more of those showers throughout your day into tomorrow. But right now in Ketchikan, mostly cloudy skies. The more south you go, the more dry you will be in terms of that rainfall. Temperatures sitting in the mid-40s across the region. And even right now, sitting in the mid-40s, even into the upper 40s in Sitka, but more rain is continuing on right now into the overnight hours and into tomorrow morning. As we look ahead, that's where you'll see those showers persisting into tomorrow morning. Drying off just a little bit more through the afternoon, but you'll notice that next round of rain really picking up by Tuesday afternoon, mostly for these northern areas of the region. The precipitation is going to build rather quickly by the time Tuesday rolls around, but this includes what you'll see tonight and tomorrow. So, this isn't really a great way to measure it, um um especially since I forgot to put a pause point there, but you get the idea. More of that rain heading your way. Heaviest amounts expected in Yakutat, as well as into Juneau.
Those winds are expected up to about 35 mph for Skagway, and you will see some breezy conditions at times for Sitka and into Juneau. For tomorrow, brace for more wet weather. Keep your extra toughs on you, your rain jacket. Just be ready for more of those showers expected.
Temperatures will be in the mid to upper 50s, I guess low to upper 50s, which is quite the range, um but near 60° into areas like Skagway. Now, for the next 7 days in Juneau, again, more showers are likely for Tuesday. That's not really going to happen until the afternoon hours. And for Monday, mostly through the morning, but temperatures otherwise sitting in the low 50s all throughout this entire week. Now, for Fairbanks right now, lots of that sunshine, and it's looking great. Pretty warm in mid-50s right now, something I'm sure a lot of people in South Central wish they could say. Current temperatures across the entirety of Fairbanks sitting in the mid to upper 50s, and even some areas like Manson Ridge just a little bit cooler at 47°.
Across the interior right now, a little bit of cloud cover beginning to roll in this afternoon. I know we did see kind of a little bit more of those clouds throughout the day today, but those are in the way upper levels of the atmosphere. Not really a lot of moisture there. That's really for the lower levels of the atmosphere, but brace for another repeat of yesterday and even today into tomorrow with temperatures sitting up into the 60s across the region. And I mentioned it was going to be pretty dry, and you can already see that on our uh satellite, I guess, if as we look ahead, our future cast. Some isolated spotty showers at times, but otherwise, you are staying mostly dry and lots of that sunshine. You can see that kind of dry line passing through the interior of the state all the way into the Seward Peninsula. That's going to move through by Tuesday morning.
So, in terms of that rainfall, nothing you need to worry about. If anything, very, very, very light, just a quick sprinkle and then it's over, but otherwise, partly sunny skies expected for Fairbanks tomorrow. That wind advisory still in effect through tonight, but highs will reach into the mid-50s to the low 60s. Now, for the North Slope, mostly cloudy skies are expected with some light showers expected in Anaktuvuk by the afternoon.
High temperatures will reach into the mid-20s. In Western Alaska, keep that winter weather advisory in mind for Gamble. Any kind of snow you're going to see is going to happen overnight and into the early morning hours tomorrow.
That's when that winter weather advisory is is going to be issued from today now until tomorrow at 10:00 a.m. Now, those flood watches are still in effect for areas like Gamble, or I'm sorry, not Gamble, for areas like Buckland and even into Galena. So, keep that in mind, ice breakup is still underway. And you can find more updates not only on our website, but also with the National Weather Service as they do their river watch.
Now, to the Aleutian Chain, very light rain's expected in Unalaska, but you'll see that rain picking up yet again in Adak. That's where that next storm is starting to brew.
Temperatures sitting in the mid-40s for the region, but just lots of wet weather expected in the Southcentral region of the state. For Fairbanks for the next 7 days, partly sunny skies ahead with even more sunshine expected into Tuesday.
Very spring-like temperatures, regardless of the sunlight, you are getting these warmer temperatures sitting in the 60s all week long. That's something you can look forward to.
Meanwhile, in Anchorage, lots of those low-lying clouds. Temperatures feeling a bit cooler in the mid-40s right now.
We've even reached down into the low 40s overnight tonight, and that's what you can expect into tomorrow. Hillside reaching into the 30s right now, but that's just a trend you can expect with these higher elevation areas.
Sitting in the 50s right now, but we are still on the cool down as we approach the overnight hours. Current conditions, more of that rain for coastal areas, inland areas like Anchorage and Palmer staying mostly dry, but we will see a little bit of those showers popping up throughout today.
Um you did see a few of those raindrops in Anchorage and you can expect a couple of those into the overnight hours. Now, over the last 24 hours, again, we had close to 3 in of rain in Portage Glacier and 3/10 of an inch in Seward and into Homer. More's expected into tomorrow.
You can see 8/10 of an inch in Cordova.
Even even more rain to come. You can see as the overnight hours approach, you're going to get another quarter of an inch in Soldotna, Seward, uh nearly a half an inch of that rainfall for the Copper River Basin. That's where the heaviest amounts of rain are always likely to be found and more of that is to come by tomorrow and into Tuesday morning.
Looking ahead, there's another view of that future track that I showed you Monday afternoon, getting that next very small front passing through areas like Kodiak and Homer, Seward, Copper River Basin and then Tuesday, we'll get that second front system that's going to push in. Now, winds are tapering off into the overnight hours. We had fairly windy conditions, but I wouldn't say they were super extreme. Uh not as bad as were originally forecasted, but still brace for some breezy conditions at times into tomorrow and through the overnight hours tonight. Most of those winds though have subsided for for the weekend. Now, for tomorrow, lots of that rain expected in Kenai, Seward and into the Copper River Basin. Light rain for Kodiak and Homer, high temperatures sitting in the mid-40s, even the low 40s for areas like Whittier and Valdez. Overnight lows dropping into the 30s. But for the Mat-Su Valley, mostly cloudy, mostly dry. Wind gusts up to about 30 mph in Palmer and similar in Anchorage. High temperatures in the low 50s and that trend is only going to continue as we get through this next week. Now, for Monday there is a chance you see some light rain but if anything it's going to be like what was happening today. Just a couple drops here and there. Nothing too crazy. If anything you will see times of that sunlight popping in, which is going to be nice. It's going to feel good. So, if that happens, be sure to go outside and take in as much as you possibly can in that short amount of time. Um but I'm going to send it to a commercial break and then after that we're going to have an extended interview uh that I did with Rick Toman last week. So, if you hear any timestamps as in if he says today or tomorrow, that was from last week. So, just keep that in mind. But it's all about the the green up season, how this year fares compared to other years in the past. So, yeah. If you have any questions on your forecast, please feel free to leave any comments and I will do my best to get to them. But in the meantime, uh stay tuned and I will have more coming up.
>> My first question about the green-up season is how exactly do you keep track and keep record of the green-up each year? Cuz I feel like it's kind of a subjective thing. So, how exactly do you record it?
So, here in Fairbanks, we're very fortunate. Uh back in the mid-1970s, uh ecologists at UAF started just jotting down the date that Chena Ridge, as seen from their office, turned green. And that has been continued um unbroken since then. And And that is uh easily the longest uh period of record we have for green-up. So, the key there is we're observing the same hillside from the same location over um five decades now. So, that's really important. There are some shorter-term uh green-up records, um places like Denali Park um that are that are maybe 15 to 20 years old. The key though is always picking the same place from the same vantage point. And that's important uh for consistency, but also when we talk about green-up, what we're looking at is not an individual tree. We're looking more at that landscape scale. So, that's why having a little bit of distance and picking the same area from the same angle is so important to that consistent uh record. Mm. Absolutely. And has it started to get green just a little bit over in Fairbanks.
Um so far in Fairbanks, um no green up.
Um things are are getting there. Uh in some in really warm locations like downtown, um just over this weekend, we're starting to see those buds pop out. But when we're looking for green up, we really are looking for when those when the leaves burst out of those buds, and that has not happened yet. Might happen later this week. That's our best guess at this point. Awesome. Well, I look forward to it cuz I love the greenery, and I know that a lot of other Alaskans do. But aside from, you know, the vibrant colors, why exactly is green up important?
So, green up, of course, is part of the seasonal round of the boreal forest. Um uh in many places in in Alaska that have uh birch trees, of course, we're in the middle of birch syrup uh or birch sap tapping right now that many folks will make into to syrup. Um so, that's going on, and that precedes green up. When green up gets close, of course, that's that sap starts to get cloudy color instead of clear, and that's another sign that that green up is impending.
Once we get the Once we get the the leaves on the trees, of course, it actually has a weather and climate connection because those leaves, of course, water is is uh evapotranspirated through those leaves into the atmosphere. And so, afternoon humidities will become higher just because you have those trees moving water from the ground up through the trees and out uh through the leaves. So, there's more moisture in the atmosphere.
Important consideration uh in shower and thunder shower development around Alaska during the early summer.
Mhm. And speaking of, you know, thunderstorm development, I know we've already seen a little bit of those uh you know, red flag warnings being issued. So, fire season seems to be upon us and more of that lightning. But, aside from that, how does the 2026 season compare for our green up compared to other years?
So, it certainly is significantly later than many years, mostly because we just have not had sustained warm weather.
Temperatures in Anchorage up through today have not yet been above the low to mid 50s. Um here in Fairbanks, we finally had our first 60° temperature here on Saturday, 62 yesterday. But, everywhere we just haven't had that accumulated warmth, and that's really what the trees need. They need that accumulation of warmth to get the sap flowing and then for the leaves to go. We're getting there, but we're definitely later than normal.
Would you say that Fairbanks' cold winter that we just had and Anchorage's cold spring are directly direct impacts to what the green up season is looking like right now?
So, based on our work, the winter temperatures don't really matter very much at all. It's really that the what happens in the spring. So, the fact, for instance, that March was very chilly. Um in Fairbanks, there was no above freezing temperatures at all and hardly any in Anchorage and most of Southcentral. So, that certainly slowed it down. What happens in midwinter doesn't appear to to have much effect.
Um the tree The trees are evolved to handle those really cold winters, so it's the spring temperatures that matter. Particularly, the kind of the the cool or at least not very warm daytime temperatures that we've had in April and so far in May are really keeping things at a slower pace than is typical.
And do you think that Anchorage's cold and wet spring that we're seeing right now, not only affecting the green up but does that have anything to do with what the summer could look like?
Um, probably probably not a good correlation with with summer weather. Of course, an advantage of the cooler weather, wetter weather this time of year is of course South Central during warm dry springs that fire danger increases pretty quickly. With the cooler and wetter weather we've had kind of put the brakes on that early start to the wildfire season.
So, would with the wildfire season, would you say that an earlier green up would indicate a less likely or a less significant fire season or a later green up would associate with a stronger fire season?
In In general, what happens in the spring determines that start. When does the When does the wildfire season really kick off?
Um, but how much acreage has burned by the time we get to Labor Day, that's going to depend really on the weather mostly between Memorial Day and the 4th of July. If it's a hot, dry late May and June and there's thunderstorms around, stuff can get going and that can that can of course last into the late summer.
If it's a cool, wet not thundery June, then it's really hard to get big wildfire seasons because our wildfire season here in Alaska is intense but it's very compressed time-wise. Mhm. And you mentioned that with the green up in Fairbanks, it's hopefully coming soon, hopefully this week or next. In Anchorage, what do you think? Do you think we're going to see that soon?
It looks Anchorage is running behind Fairbanks in in that accumulated warmth.
That's of course normal at this time of year.
Uh, doesn't really look like though for Anchorage it probably not going to be this week, maybe next week.
Okay, perfect. I look forward to it. And >> on your in your personal opinion, what is the most interesting aspect of the 2026 season so far? I mean it's been a wet and cold spring for Anchorage. The interior had a pretty cold winter, but overall in your opinion, what do you think is the most interesting aspect?
Well, certainly for this spring really Anchorage, South Central, Fairbanks, most of the interior, the really cool days that we've had persistently is really quite interesting. For instance, April temperatures were not very far below normal anywhere, but if you look at it in detail, it turns out because of the kind of the cloudy and in some areas damp weather, the average daily low temperatures were near or even a little above normal, but the daytime temperatures have really been down. Here in Fairbanks about 85% of the days since March 1st, the daytime temperature the high temperature has been below normal and it's much closer to 50/50 for low temperatures. So that's cool daytime temperatures in in Fairbanks, South Central, really quite quite interesting and it is certainly playing a role in both the timing of snow melt and now that we have green up coming.
Mhm. I have definitely been feeling those colder temperatures. And my last question for you is is there anything that I haven't asked you yet that you want to talk about with green up season?
Um so it is important to to remember when we talk about green up the database that we have here in Fairbanks and it and it has been built on when basically birch and aspen leaf out. So, we're not we're and again we're looking at the hillside. So, you know, non-native trees could could leaf out at a different time.
Um and and the the procedure that we developed for forecasting green up in Fairbanks, it seems to work pretty well for Anchorage. That's not a big surprise, right? Still boreal forest, same you know, roughly the same latitude. When when we've tried to use this exact same methodology it at lower latitudes, say Western Washington or Southern British Columbia, it doesn't work very well and that's not surprising. Entirely different forest much farther south. So, um again we're looking at birch and aspen trees when they leaf out and that landscape scale. And it's good for here in Alaska, probably would work in the Yukon as well.
So, with Fairbanks you monitor the Chugach Hills and you monitor whenever that's blooming. In Anchorage is there a specific area that they focus on to watch the green ups? So, what we what we ask folks again is is pick an area that where where birch and aspen are the dominant species and again try to look at that look at that from a little distance so you get that landscape scale not just focused on one or two trees. Uh but we don't really have a consistent data set like that for Anchorage.
We would love to.
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