Friday, December 5, 2008

Next Weeks Storm

Let's put the weekend clipper system behind us for now. It is pretty much a lock for a 1" snowfall on Saturday.

The big question looming is the Tuesday system. It has trended west/northwest a bit in the 12Z model runs. That is good for the precipitation. The bad news is the temperatures are too warm. For snow to fall, you need a small handful of items to occur.

You need moisture/precipitable water, a thickness pressure of 540mb, and the surface temperatures and 850mb (5000') temperatures to be below freezing. A warm southern flow which is making a nice transport of moisture from the gulf is also bring up warm temperatures.

Both the surface and 850mb temperatures are marginal at best. There should be some backside snow but the font end would be loaded with rain. That is nothing but bad news for snow lovers.

If there was some good news in this is there still is a lot of time between now and the actual storm. The models have also done a lot of flip-flopping back and forth on temperatures for the week including the Arctic blast Thursday through Saturday. Just 36 hours ago it was forecasting Friday to be all below zero and now has it teens. It has gone back and forth with each model run.

I suspect the best thing is to take a wait and see approach for now. The clipper could make some subtle changes to the overall pattern which could be good for us wanting snow. I think my call will for the snow amounts will come Sunday evening sometime. Until then, I just keep hoping.


Snip said...

Jim, please don't let it snow until Wednesday -- after the NES Christmas programs.

Jim said...

I think you will be safe from the looks of things. The warm air keeps moving up and will make any snow threat dissapear.