Livin’ on a prayer (49% chance of cancelation)

Today’s model runs have been … all over the map. The GFS, which had taken snow south of Eau Clare, has brought it back to the Birkie. Not much, but 4″ would be enough as long as the base is somewhat intact.

The European pushed the storm south. The Canadian kept us on the edge.

It doesn’t look good, but it’s not hopeless. A lot will depend on what happens tomorrow with the rain having come through. If the base north of OO (I’ve mostly written off a race south of OO unless the storm comes way north; if Fish Hatchery is hosting a trail run on Thursday, well, that doesn’t bode well) survives, I think we have a decent chance. If there are small holes that can be patched (water courses, etc) I think we might be okay. Having the race on Saturday, after some cold weather sets in, helps a lot: if the race was scheduled for Wednesday we might be sunk. If the course has washed away to grass, though, we’ll really need a miracle.

I’ve updated my numbers. I think we’re really right on a 50/50 line of salvaging anything.

Now, I might have to write my unofficial guide to still having fun at the Birkie even if you only get to ski 25k.

Do you believe in miracles? Not yet …

No lake? No lake. (47% chance of cancelation)

The lake is out.

The lake is a flowage: a dam across a river. If there’s a lot of melt and rain, the lake flows. If the lake flows, the ice becomes unstable, and you don’t exactly want to ski across it. So that has happened.

image1 (1)

This is Wheeler Road down by Duffy’s Field, we think.

Reports from the rest of the trail, at least south of OO, don’t sound so hot, either. Here’s my best guess as to what is going to happen, assuming the north end of the trail is at least mostly intact:

  • The Korteloppet will run from OO to Cable (or Cable to OO, depending on which direction makes the most sense).
  • The Birkie will run from Cable as far south on the trail as is possible, which will likely depend on how much snow (if any) falls on Friday. The latest model runs are all putting the Birkie right on the edge of the storm, so that will be a wait-and-see.

So the news today is … not good. If the storm comes north and drops enough snow, we might do fine. If not, the best we can hope for is a 25k Birkie to OO, much like 2007. In 2007, the storm hit on Saturday night. This year, it comes a day-and-a-half earlier. We’ll keep an eye out on it.

It’s the US vs the World (37% chance of cancelation)

Twice a day, we get three different models at the same time. At noon today, the Canadian and European models looked juicy for the end of the week: snow and cold for the Birkie. The American model? Not so great, again. It is cold for Saturday (and Friday, for that matter), but suppresses the low far south, far enough that the Birkie would see little more than flurries.

The latest from the trail makes me wonder if there’s much of a chance of keeping the snow through the race on much of the trail: two inches has already been lost with four warm days to go. So I’ve upped the cancelation probability to 37% (there’s a formula for this, below), but there’s still a decent chance of having a race.

How do I calculate these guesses? First, I estimate the chance that snow will come and save us. That is calculated by taking the proportion of the models giving us enough snow by Friday evening for a race and dividing it by the model pessimism adjustment rate (generally, 2). So if two of three models give us snow, I give a 33% chance that the snow will save us. Then I take the probability that the whole course will have snow and that just the north end will. Add it all together, subtract from 100, and get a cancelation percent. My guesses right now:

  • Probability of snow: 33%
  • Probability of part of the trail surviving: 30%
  • Probability of the whole trail surviving: 15%
  • Probability of cancelation: 37%

Two out of four (30%)

The overnight model runs are in:

The Euro looks great.

The Canadian looks great.

The American model looks … well, the most recent version brought a bit of snow in, while the midnight run was dry. So maybe that’s the right direction? It at least looks like there will be enough cold air in place for the race that whatever snow is left will be frozen solid. But it would be nice to have something on top.

Waiting … (30% chance of cancelation)

In recent posts I’ve used a football metaphor regarding the chance of a snowstorm saving our behinds for the Birkie. Since it’s 50 in Hayward, here comes a baseball metaphor:

It’s the bottom of the 9th, two out, runner on second, down a run. If we get a double or better (6″ or more) from the storm, the race will be great. A single (3-5″) may be fine, depending on how much base is left, but the runner could get thrown out at the plate. Any kind of out? We’re probably sunk.

Right now, we’re hitting about .500. The most recent models, to go back to football, have been shading towards a miss wide-right, putting snow down in Madison and Chicago but not on the Birkie Trail. But last night the models were missing wide-left, with rain on the Birkie Trail and snow up in the Arrowhead. The weather in Hayward today was warm but dry: so the base probably did okay. But there’s a lot of weather to come.

Some people have emailed me asking about weather models and where I get them, so here you go. For the GFS and CMC, poke around TropicalTidbits and PivotalWeather; you can also view model output at wxweb and the Bufkit Warehouse. The ECMWF is proprietary and you have to pay to access it, and we don’t have enough money for that yet (support our advertisers!) but you can view output from the Norwegian Meteorological Service (long story as to why, and as to why I know) here.

Podcast Episode 7: Ben Popp Updates

The latest episode of the BirkieGuide.com Podcast is dropping (well, uploading) as we speak (especially if I upload them to the right directory). We talk with Ben Popp, the Birkie executive director, about the current status of the course, the chances of a good race, and preparations and contingencies. He’s realistic but optimistic: the base is solid and helped by rain which solidified it in January and earlier this month. He says there’s a 75% chance we survive the meltdown.

(Model update: the latest US model was very bad, but the latest European model very good. It’s wait and see at this point.)

55˚. 36% chance of cancellation

The forecast high in Hayward today was 47˚.

Right now, it’s 55˚.

This is real bad. It’s 55 and sunny, which is better than 55 and rain, but still baking away at the base. The hope was that fog or low clouds would mitigate the melt somewhat. That looks unlikely.

On the other hand, the European model prints out a direct hit for the Birkie next Thursday and Friday with 12-18 inches of snow falling, starting Thursday night. We’re now banking on that. Here’s my best guess at what may happen next week:

  • 6% chance the race is held on the current base
  • 18% chance the race is held on the current base, but is shortened to or turned back at OO
  • 40% chance the race is held based on new snowfall
  • 36% chance the race is canceled due to lack of snow

With the current weather and upcoming warmth, we are really banking on a Birkie Blizzard. It’s not a good place to be. But it’s better than canceling a plane ticket.

9 (warm) days to go

We still have a problem. It’s going to be warm for the next week. Five days above 40, potentially two above 50. This is no bueno. It may cool down some evenings. It may rain. The snow may last. But it will be close. It may not.

We’ve had a good run of snow years for the Birkie since 2007: the longest run of a full course being run since the 1990s. Good things may come to an end. But they may not.

I think retaining a good base with the upcoming weather may be very difficult. But if we can retain something on the ground, anything on top helps us a lot. And there’s a strong signal a week out that we may see some snow. Most of the model runs in the past few days have shown this; the ones which haven’t have shown the storm being suppressed south by high pressure. This is what to watch. Today, we’re 2/3 on models showing the storm hitting the Birkie Trail with enough snow to give us a race next week. We’ll have to watch this, closely, over the next few days. For now, if you’re a praying person, pray for snow.

(I’d like this year closest to 1998, when there was 6″ of snowpack and a week of temperatures in the 50s. That year the race was shortened to OO. Hopefully we can get a bit better.)