1/25/2011: Insert Uncertainty Here at 11:30 PM

Will it snow? Won't it snow? Is it time to write the winter off?

Maybe.

I famously proclaimed no more than three days ago that winter was over this year. Dead. Gone. History. Put it in the books as a lost cause. Relegated to the past tense.

There is still a very real chance that this is true, but there are also several reasons why it may not be. Let's look at Tuesday/Wednesday, eh?

Three options, every single one valid. Nothing, snow with precipitation-type issues, or rain. There are a lot of similarities this time with the Boxing Day storm (day after Christmas for the Americans), but also some very large differences.

You'll undoubtedly recall in some of my postmortems analyzing what's gone wrong this winter that the blocking (causing this crazy cold winter we've had) has been exceptionally strong. You'll also recall that the PNA was causing a shift in the storm track which was also messing with things.

Well, the blocking has eased up dramatically and the PNA has shifted to a weakly positive area (not ideal, but better than before). What that means is there's the possibility of a better track. One that's not crazy offshore. I still don't buy this system. Of course it's a lot easier to be pessimistic this winter than not, especially after I've just detailed several reasons why it's wrong for me to be pessimistic.

The pattern this winter has been for 4-6 days before a storm, things look great. We're in the sweet spot. The bullseye. As the storms get nearer and the actual systems get onshore where there is better resolution in the models, they vanish, and the northeast gets a huge amount of snow. We get a dusting, and I get angry.

This particular storm has been particularly crazy. It's a weird pattern and every model has said something different. The one at this range that has traditionally been the best was calling for a complete whiff until 20 minutes ago (and is now calling for 6-10 inches of snow, perhaps with some mixing). The one that will be good in 18-36 hours was calling for all rain (and a lot of it). The European, which has been off all winter, is calling for a decent snowstorm for this area. The Canadians and Brits split the difference.

The more I think about it, the less I like a complete whiff. I think something falls from the sky. I just don't know what yet.

What I do know is this: there's going to be an extremely sharp cutoff line of precipitation. Once again, similar to the Boxing Day storm, 50-100 miles is going to make a difference. Within 100 miles you could see two inches of snow on one end, a foot in the middle, and an inch and a half of rain on the other.

DC should have precipitation-type issues. It could start off as snow (with some cold air dammed in), change over to rain, and then back over to snow after the system is on its way out. Goodness knows the streets need the salt washed off of them.

The thing that has me most intrigued is looking at the ensemble members of the models. The operational mean (which has the most resolution and most closely mimics current conditions) is also the farthest east. The ensemble members, which vary the starting conditions, but also has a lower resolution of data is very much farther west (which yields a heavier snow event, or snow/rain). Something like two-thirds of the ensemble members give us a lot more than the operational mean.

If you've read this far, good for you. I'm finally coming to a conclusion. Almost everything I've said above contradicts with itself at some point, beginning, middle or end. Just like the models.

If I had to pick, based on the seasonal trends I think we're looking at a light snow event. My gut tells me though that there's a better chance this time than previously, but I think we get screwed the other way. Rain. And if we get rain, then the Shenandoah makes out like a bandit, which is far more climatologically accurate for this kind of winter.

Could I be wrong? Highly likely. But anybody who tells you what's going to happen is lying to you anyway.