It’s Snow Hard to Make an Accurate Forecast!
Some of you have previously heard me lament about the difficulty of weather forecasting. I like to give the example of the surface of ocean with its gazillion little waves that ripple along the top. The spectrum of wavelengths is almost literally infinite. Now imagine trying to write an equation that could explicitly determine what the wave pattern looked like at any given instant on the water’s surface. Pretty hard stuff, considering that the answer would, simplistically, be the superposition (sum) of all of those waves of varying size that we talked about before. In this example, i have really only described one layer…in a sense, just a two-dimensional sheet. But, of course we want to know more. We need all three dimensions and so even if you had the answer to the first layer, you’d still need many, many more layers just like that one in the vertical. AND…this is only predicting one quantity. You still have to do the same thing for four or five other variables! Do you get my point…or have i driven you into a nacroleptic seizure? The point is that it’s amazing that we can predict much of anything given the scope and shear magnitude of the task at hand…which is to make deterministic forecasts for a gazillion individual points (using an incomplete set of equations, i might add).
So, with that perspective in mind, determining where a low pressure system will track within 25-50 miles, 24hrs from now, and given the fact that it hasn’t really developed, would be a job well done. Unfortunately, that 50 miles could make the difference between 1″ or 5″ of snow…or an even harder to resolve…dusting or 3″. All this is to say that the game is about to start and the players are getting the normal pre-game gitters.
Nothing I’ve seen tonight in the new model runs really changes my thinking from earlier. The stronger, outlier solution has come in more reasonable with it’s QPF this evening, which is a bit deflating for the glimmer of hope that you always hold onto for the forecast bust that could go explosive like the January 2000 blizzard. So, to sum it up…a little rain in the morning before we change over to snow about 11-12noon. I’m looking for 4″in Raleigh. The storm will be much more established tomorrow and therefore a more predictable entity than it is tonight in it’s infantile-state. More then.