Getting in clown range

Weather nerds¬†sometimes speak of “clown range” for weather models. Clown range implies that, beyond a certain time frame, the weather models are about as good as a clown predicting the weather, usually beyond about seven days. But for very wide-scale trends, there are ways to read tea leaves to discern large-scale trends: wet vs dry and warm vs cold. Will it be 0 or 45 on race day? Who knows. But even a month out, we can say whether there is a greater likelihood that it will be warmer or colder than normal: we were worried in early February of 2017 because the models painted a picture of very warm weather four weeks out and look where that led.

So far? So good. The next two weeks look warm-ish (but not snow-melting-warm) and then cold-ish. And beyond that? Normal-ish. I’ll take normal-ish with a good base in place. Normal-ish doesn’t melt two feet of snow. And normal-ish make for some of my favorite Birkies, like 2009 and 2010: cold to start, warm and sunny by afternoon.

But I’ll take anything with 50k of snow on the ground to Main Street, frankly.

 

One month to go (or so)

So, time to fire up the old Weather Speculation machine!

Long story short: I think we’re in decent shape.

The next two weeks are warm. On the long-range maps, they show up as anomalously warm by 2 or more standard deviations. But anomalous warmth can be either good warmth (not too cold with some frozen precip to build the base) or bad warm (high temperatures or rain which eats the snow). And the next couple of weeks look like good warm.

For instance, the normal high in Hayward today is 22, with the normal low of -1. The next couple of days will sit right around 32 with some light snow or wintry mix. Not enough to add to the base, but nothing that will remove it either, and with last week’s storm, the base is in pretty good shape. For the rest of the week, the temperature will remain between 20 and 35, but it will stay dry. So is this quite warm? Sure, but it won’t do anything to the base. I’d much rather have this type of weather than temperatures of -10 followed by a rain storm.

This pattern may continue clear into early February, before it finally cools down. Not much new snow, but nothing that appears to be a major meltdown. I’d actually rather see this followed by a cool down closer to the Birkie than the other way around. Weather is cyclical, and a few warmer weeks are often followed by a few colder weeks. If we can survive the warm and get into a colder cycle come Birkie, as the models suggest, we’re in good shape.

Obviously, a ton can change between now and race day (and a lot will). And one of the best things on our side this year is a reasonably early race: February 22 rather than the 27th or 28th.¬†If we assume that in any given year, the chance of the Birkie happening is 90% (since it’s been canceled about once a decade in its history) I would put the chances of the race happening, given current conditions, higher than that, in the neighborhood of 95%.

Ski on!