Wednesday, November 30, 2011

Today is a prime example of why I hate snow!

 I sit here under gorgeous sunny skies and the temperature is 44 degrees. 44? Cool, right? Yes..of course it is. But with the sun and lack of wind, for November 30th, is really not that bad. In fact, with the sun on you it's pretty nice.

However, IF we had snow things would be far different.

Let's take a look at the latest satellite image, with a surface plot overlay (courtesy of NexLab/COD, http://weather.cod.edu/)

Click to enlarge

The arrows point to the main snow band, a result of snowfall from yesterday's storm. This fresh snow cover is limiting temperatures to the low/mid 30's today in the snow covered regions. In addition to the slushy mess that results from the melting snow, one would have to deal with temperatures at least 10 degrees cooler, if not more. And tonight? The snow will aid in substantial cooling, that we will not have to share.

The RUC model shows this well ...

Click to enlarge

The model is likely overdoing the extent of the cold air, but you get the idea. Naturally, this enhanced cooling tonight will serve to retard any large warmup tomorrow simply because the temperature will start from a far lower reading.

Understand, too, that this is a minor example of snow's effect. In the deeper winter, snow serves to aid in far more cloud cover, warm-ups that never make it, etc, etc. It doesn't only affect the highs today/tomorrow, it can allow temperatures to be colder for quite some time.

So I'll enjoy the "slushless" day, the roads without salt, and the ability for the sun to heat us to the maximum capacity. :)  Tomorrow (and beyond), any warm air that tries to make it here will not be impeded. Days like today remind me how much I'm thankful for that.

[Science reason, in very small detail: Sun shines with certain amount of energy. Any energy that goes to melting the snow (phase change) as well as energy that bounces back into space off the white snow subtracts from energy that could go to heating the air.]