Weather Speculation: Backing away from the ledge …

The past couple of post have been a bit vague about how bad the threat of a huge warm-up looked, because I wanted to hedge my bets and not be a huge Debbie Downer. And, as often happens in long range weather speculation (there’s a reason I don’t say “forecast” here), things have changed. Luckily for the better (also known as “reverting to the mean”). Now that the threat seems to be ebbing, here’s what I saw, what I’m seeing, and what it might mean.

Screen Shot 2017-02-08 at 10.42.49 AMHere’s what we saw about a week ago. This was the four week extended model at that point showed a large positive temperature anomaly stretched across the continent: the kind of temperatures which would lead to 40˚ temperatures in the northwoods which could eat away at the base. (See the map at right.) The weather models didn’t look much better, with temperatures looking to take a week-long ride above freezing.

This persisted for a few days, but recent maps have looked a lot better. We’re still looking at some positive temperature anomalies, but not to the same extent. The shorter-range models do show some warming temperatures this week and next, but staying in the 30s, with little liquid precipitation and the chance for some snow. And the week of the Birkie itself looks cooler, so we shouldn’t have a repeat of last year.

All this, of course, can and will change. There’s very little skill predicting the temperature out beyond a few days, and anything past a week is generally just looking at trends. Still, I’d much rather have trends point to normal temperatures than way above.

 

Weather Speculation: Is the trend our friend?

Last week, we wrote about how the long-range weather forecast for the Birkie was sub-optimal. Since then, it hasn’t gotten much better, but it hasn’t gotten any worse, and there are some glimmers of hope. Looking out 10 to 16 days on the models is always a dangerous exercise, and we should look only at bigger picture trends, not specific events. The US model, which goes out to 16 days, is promising. The last few runs have dampened the western ridge somewhat, and kept Wisconsin on the eastern fringe of it, keeping temperatures from skyrocketing in to the 40s. The European Model out to 10 days mostly does the same. The US model even shows some additional snowfall before race day. It’s still a low-confidence forecast, and there’s plenty which could go awry, but for now decent snow conditions appear possible.

Less than three weeks to go!

Early Weather Speculation: Snow, then Warm, then ?

It’s February, so it’s time for some early Weather Speculation posts on BirkieGuide.com. Last year, you may remember that it was warm for the Birkie. There was plenty of snow, but the race took place in the middle of a thaw, leading to somewhat sloppy conditions. This year, a similar pattern is setting up, but it might come earlier, and the race may be cooler, but since it’s more than three weeks away, there’s not that much that we know.

Right now, snow depth in Birkieland is about a foot. It’s a good base, but it’s far less than we’d like at this juncture. That may change, soon, for the better. All signs point to a potent storm affecting the Upper Midwest in the middle of next week. The question is exactly where it will produce snow, and how much (actually, that’s always the question). Right now, models range from a few inches to upwards of a foot. A foot of new snow would go a long way towards calming the nerves of some Birkie skiers.

Then things get … interesting. There’s extreme, unprecedented heat in the arctic this year and weather patterns are not relatively well behaved. Several models—the US model in particular—have been toying with a huge ridge building over the western two-thirds of the country in the third week of February. This could bring a prolonged period of well above-normal temperatures to the Upper Midwest. This is still well out in the future, although the longer range outlooks are not pretty.

Having said that, there’s a lot that could mitigate this. First, it’s more than 10 days out on the models, what meteorologists sometimes call “clown range.” Second, it looks relatively dry, which could mean above-freezing days, but below-freezing nights, which would at least mitigate snow loss. Third, it appears that the heat may break before the Birkie, so if the snow lasts, the race could go off in more suitable conditions (i.e., no water skiing on the lake). Fourth, the axis of the ridge has been wavering east and west recently on the models. Some runs, it winds up centered over the Upper Midwest, and in others, it shows up much further west, over the Rockies, with colder air in place over Wisconsin.

So there’s a lot to watch. I wouldn’t get too worried yet, but if it doesn’t snow next week and the warm air pushes in, we may have a problem.

Panic! Everybody panic!

Okay, don’t panic too much. It’s raining. It’s warm. It is going to be interesting.

As far as the weather goes, the last couple of forecasts have pulled down both the amount of rain (0.1 to 0.25″) and the overnight temperatures (in the 33˚ range, yes, that’s right, 33˚). But the rub is that the snow may be quite a bit colder. The underlying snowpack is very cold—it was -20 in Hayward earlier this week, and -13 even after the most recent snow—and the Birkie hasn’t groomed the snow on top to attempt to insulate the base.

In other words, East Coast conditions. So what might this mean? If there is enough warm temperatures and rain, the entire snowpack may transform and soften. But it might not get quite so warm and the top of the pack may transform while the bottom stays a bit more frozen. And in either case, even if it doesn’t drop quite to freezing on Friday night, if it’s calm enough the temperature of the snow may fall enough to freeze it up, which may vary over different parts of the course. The cold base and cold ground will radiate cold temperatures through the base and perhaps in to the air slightly above, and in sheltered areas the snow could freeze up quite nicely. It’s certainly possible to have packed, icy conditions even with temperatures above freezing.

Or it could be a slushy mess. And if the temperature only goes to 36 or 37 during the race and the sun doesn’t come out (likely) then it might stay pretty solid through the race. All things considered, this would not be the worst outcome given the weather. We’ll see at the start line.

Weather speculation: the picture gets … clearer?

We’re going to have a ski race on Saturday.

The weather is going to be … interesting.

The Birkie hasn’t flirted the freezing mark at the start, except for the 2007 debacle, in nearly a decade and a half. The last few years have been cold. And this year? It is not going to be cold. It is going to rain. It’s not going to be warm enough and rain enough that the course will melt off and disappear, but it’s not the usual ski forecast of “soft ski, fine grind, hard wax” for glide and “something in the neighborhood of blue” for kick.

So let’s get to weather. It’s been cold in Birkieland for the last few days. Like -20 overnight cold. So the base—a foot-plus in the woods packed on the trails—is cold, and the ground below it cold. That’s good. It’s going to get warm. Not hot, but certainly warm. On Thursday, after a chilly start, temperatures will rise in to the mid-30s in the afternoon, and won’t go down overnight, making a run towards 40˚ in the overnight hours. On Friday morning temperatures will be in the high 30s with a burst of precipitation, about a third of an inch of rain, falling (maybe less, maybe as much as half an inch; the models aren’t particularly congealed yet). This will be with a passing cold front but that will usher a drier but still Pacific-origin air mass, so it won’t get much colder.

Friday will stay in the 30s or maybe low 40s during the day, which may vary across the trail. What this does to the snow will be interesting. The rain will fall and percolate down through the pack, but may freeze in to the snowpack more than anything since it will retain a lot of cold. There should be enough time for it to freeze in and drain away before the race on Saturday, but it will be interesting. Friday night will be very interesting: temperatures in the 34˚ range will make for a much different race than temperatures in the 29˚ range. Although if the trail is packed, it might freeze up well enough, at least for earlier racers. Right now, it looks like it will drop to right around freezing, maybe a little above, but different parts of the trail may behave differently. So, really, all bets are off in regards to trail conditions.

Saturday appears to be in the mid-30s, breezy, mostly cloudy with a west-northwest crosswind. It will be like 2007, actually, except without a) a shortened race and b) a snowstorm in the evening.

As for the base, it should be fine. In 2000, a fifteen inch base was vaporized over the course of a week before the race (see the chart below). This year, luckily, the meltdown will be much more muted, we won’t have three days with temperatures staying above 40 overnight, and won’t have highs at or near 50 for most of the week before the race. About the same amount of rain, but 15˚ colder and falling on to snow that hasn’t been pre-warmed by a week of warm weather. In other words, it’s not perfect Birkie conditions, but we should be fine.

2000: not a happy time for the Birkie (data from Spooner via NWS):

2000-02-20 38 5 21.5 3.2 43 0 0.00 0.0 14
2000-02-21 43 17 30.0 11.3 35 0 0.00 0.0 11
2000-02-22 52 28 40.0 20.8 25 0 0.00 0.0 10
2000-02-23 48 24 36.0 16.4 29 0 0.19 0.0 8
2000-02-24 56 40 48.0 28.0 17 0 0.00 0.0 5
2000-02-25 51 41 46.0 25.5 19 0 0.33 0.0 1
= No Race 52 40 46.0 25.1 19 0 T 0.0 T

Paul Huttner is calling this a mega-thaw. Well, that was a giga-thaw.

So freak out about wax, and how your body will do in these balmy conditions. But don’t sweat (ha!) the course, we’ll have snow from Cable to Hayward. It just won’t be soft and powdery. But we’ve had eight Birkies in a row with good snow and Main Street finishes, and this should, barring a major downturn, be a ninth.

Weather Speculation: Warmer

So, uh, don’t panic.

But get a little worried.

The Birkie Trail should be fine for the race as long as it doesn’t rain too much or get way in to the 40s (but, uh, it might, which could be very, very interesting). It will be warm for the 24 hours preceding Saturday morning (but it might—might—dip to freezing on Friday night) and it is not going to have the usual squeaky-snow Midwestern feel to the race. Welcome to the East Coast/California, folks! Warm and slushy or maybe icy, too.

Fluoros? Yeah, they’ll matter. Flex and grind? Yup, them too. Rilling? Oh, yeah, you’ll want to rill. Wax? Ha, klister, all klister. Get our your blowtorches, classic skiers.

And for god’s sake do not ski on the trail on Thursday or Friday.

Weather Speculation: Roll up your sleeves

It’s going to be warm.

Like, not warm enough to melt the snow, so we should have a race. But a heck of a lot warmer than any Birkie in recent memory.

Monday through Wednesday this week will be seasonable: highs in the 20s, lows around 10, with maybe an inch of snow here and there. Then it gets interesting.

Thursday should be cold to start, but warmer as the day goes on. Luckily snow goes down on Wednesday night on Main Street (I think) so it should set up well when temperatures are still around zero. Thursday will go up to around freezing, and then not go down. Friday will be the warmest day. It will likely be cloudy and in the 30s, with some light rain or drizzle (yes, rain). Nothing that will wash the snow away, but certainly something that will put some moisture in to it. The snowpack will be quite cold and retain a lot of latent cold in it, as will the ground, so it is unlikely to get soft if the temperatures stay below 40.

Then things get really interesting Friday night. Current guidance shows the low temperatures dropping to right around 30 as a weak cold front comes through. If temperatures stay above freezing, the course may begin to soften given the time above freezing. If they drop, say, to 28, the course may freeze from above and below and could be lightning fast and solid, a good day for stiff skis with good edges. Glide wax will matter, and it will matter a lot more if it’s 33˚ at race time versus 28˚. And the course may change during the race, with firmer conditions at the start that soften as we go south and as the sun comes out, which may or may not happen. Oh, and it’s possible there will be some light wet snow overnight. So as for kick wax: good luck, classic skiers. It may be a day that waxless skis take the day.

This is not one of those years where we know the weather ahead of time, because while 5 degrees makes very little difference between 5˚ and 10˚, but a whole heck of a lot of difference between 29˚ and 34˚.

This Birkie is going to be interesting. Fun, and interesting.

The good news is that Saturday afternoon may be 35˚ and sunny, so get ready for a party on the lake. I’ll get the New Glarus.

Weather Speculation: A Balmier Birkie?

1998 to 2007 was a dark period for the Birkie. The race in 2000 was canceled, 1998 and 2007 were shortened significantly, 2002 finished short of Main Street, and 1996 had race temperatures well in to the 40s; I can only imagine that it was a soggy, slushy Birkie. (Our weather history chart is here; I’ll update it soon with more recent data.)

Since then, we’ve had a run of good luck. Even in 2012, where there was hardly any snow south of Birkie, the course was perfect. The only downside has been the cold; some of the coldest Birkies have been held in the past decade. Still, eight races with pretty much perfect snow in a row is not too shabby, especially in a time of warming temperatures across the globe. If you’d told me after we skied 25k on rock skis and slush in 2007 that we’d have perfect snow for the next decade, it would have sounded like wishful thinking in a year where there wasn’t more than three inches of snow on the trail before race day.

This year shouldn’t lack for snow; there’s enough on the trail (although more would be nice) and we’re unlikely to face a 2000-esque meltdown (when 15 inches were washed away in a few days), but unlike most of the races in the past few years, it won’t be cold at the start. So you can leave your buffs, dermatone and maybe even wind briefs at home; it’s very unlikely that we’ll need a “-” in front of the temperature, at least not in Farenheit.

We might not even need it in Celcius. The two models are getting in to range, and both show a warm up at the end of next week. The European model shows temperatures peaking on Friday night just above freezing, with a mix of rain and snow falling on race morning. This would be interesting to say the least, and would cause a run on fluoros at the local ski shops. The American model brings the warm air in a bit earlier, with temperatures in the 30s on Friday, but falling back through the 20s on Friday night. With any moisture added to the snow, this would create a lightning-fast track for Saturday morning. The Canadian model, for what it’s worth, parallels the American model with a cold front swinging through on Friday afternoon.

Unless the models are wildly wrong, there should be no real threat to having enough snow for the race and a ninth straight Birkie with good snow. But it might be the first time in a while the start of the race we won’t have to layer and layer and layer up.

Weather Speculation: two weeks to go

With two workweeks until the Birkie (including Presdident’s Day; it’s so close!) it’s time for another installment of weather speculation! Last week’s snowstorm dropped 6 to 8 inches of snow and pushed snow depths in to the foot-deep range, although the packed depth on the train is less than that. This definitely helped the long-term forecast for the Birkie! Sunday’s thaw in Hayward was moderate and short-lived, and it’s now cold with a bit of light powder falling. It looks to stay cold for the next week.

Over President’s Day weekend, temperatures will moderate somewhat. Not a huge thaw at this time, but highs closer to 0˚C than 0˚F (it may not clear 10 in Hayward from Monday until Sunday). It may get cooler again before the Birkie, but there is some long-range guidance which would point to a warming trend towards race day, possibly a cool morning with a warm afternoon (desirable) and possibly some sort of storm (less desirable). This is, of course, a long way out and is very, very likely to change, so don’t make your plans based on it quite yet.

Early weather speculation

It’s February, and if you’ve followed this blog in the past, you know that means that it’s time for Weather Speculation! As usual, we look at weather models and make wild guesses about the weather, although they are at least slightly educated guesses. There’s only 19 days until race day, so we can basically pinpoint to within a degree what the temperature will be when your wave hits the course in Cable. (Note: this is a lie.) Join in!

With an early race this year and snow on the ground, we just need to worry about a warm-up. As you heard on the BirkieGuide Podcast (Wait, you didn’t listen to the Podcast? What is wrong with you! Go, go download it and listen to it now!) there is a thin-but-solid base on the whole of the trail, that could be skied well tomorrow but is susceptible to melting and could use some more snow.

So basically we need one of two things to happen. Either a) it needs to stay below freezing for the next 19 days or b) it needs to snow. If both happen, all the better. Let’s see where we stand with the long-range forecasts:

a) Cold. So far, it’s been a warm winter east of the Rockies. The City of Lakes Loppet may be salvaged by a last-minute snowstorm after warm air melted a five inch base to a thin covering of slush and ice. January has been only a couple degrees above normal, but with wild temperature swings and a late-month thaw. That has passed, and the next few days look colder. Not cold, mind you. But colder. And colder is good enough in Northern Wisconsin in February. (There’s newly-available “NowData” from the NWS for Spooner dating back to 1895. That may be downloaded.) As for the weather, the current models are not showing any major warmups in the next two weeks. In the third week things get a bit dicier with warmer air dumping over the Rockies, but it looks to stay at bay until it gets warm in earnest in March. So this is qualified good news.

b) Snow. Of course, a couple of feet of snow would help out as well. A couple of feet we may not see, but the storm which has pushed north 50 miles in the last couple of days in to the Twin Cities is similarly pushing towards Hayward. It may drop [edit] 4–8 inches of snow on the Birkie Trail (with higher amounts at the south end, which if you listened to the podcast you would now is where it’s most needed, and the totals keep going up; the trend is your friend) this week, which would make everyone breathe easier. Not a blockbuster, but not nothing. Beyond that there are no huge blizzards on the horizon, but an inch here and there. Time will tell.

As for race-day weather, it is foolish to try to predict specific days more than a week out (and certainly not three), so I am not going to. Yet. It will be between -20 and 50 at race start. And most likely in the teens.