Two runs of the American GFS forecast model have predicted a major winter storm to hit the Midwest, Plains and Great Lakes from February 21 to the 23rd.
Synopsis... The upcoming period will be an interesting one. We will be seeing the Madden-Julian Oscillation shift to Phases 3-4, and the North Atlantic Oscillation going negative. A strong negative Pacific North American index could very well act to work against such a potential, however. In non-weather speak, there are some indices that bode well for a storm system taking a path through the Midwest and Ohio Valley. However, if persistant low pressure is able to hold its ground in the West Coast, I worry that it will either shoot north into the Plains and Canada or way down south in the Gulf. One thing that I will say in this mess of uncertainty is, this American model and the more reliable European ECMWF model have the center of low pressure in nearly the same spot on the 21st. The European model does not go out past 10 days, so we will have to wait a day or two more to see how it develops this system fully.
For now, I suggest not really caring about this system. It's great to see potential and at least some model agreement, but I'm not comfortable enough with the predicted atmospheric pattern that I will definitely go ahead with this potential storm.
Andrew