Large Scale Pattern Change Possible.

This won't be as long as most long-range posts, so I'll make it quick and simple. Over the past few days, NCEP ensembles have continuously forecasted that a large scale pattern change is underway. Ongoing research suggests that Ensembles (a group of several model permutations that are either averaged for a mean value or to show the differences between the possible solutions, in which the permutation in the model forecast could be a change in the physical schemes, dynamical schemes, grid spacing, etc...) are notoriously better at forecasting long-range patterns than the actual operational models themselves. The ensembles that the National Centers for Environmental Prediction is using is forecasting a drastic and extreme change in the teleconnections. Usually, during a medium to long-range period, models forecast one or two of the "important" teleconnections (which include the AO, NAO, and PNA; Arctic Oscillation, North Atlantic Oscillation, and the Pacific North American index, respectively) to go negative or positive. This time, each variable will be correlating with each other, which has very serious implications for the latter half of October and beginning of November. They are forecasting the AO to go strongly negative, the NAO to go strongly negative, and the PNA to go strongly positive in the long-range period, which is a very good indicator that it is going to be very cold for the end of October and beginning of November. It also indicates that a very strong storm system may be in the making for medium range period, especially after the 20th of October. I will continue to monitor the situation, but as I have already stated, the ensembles have been very, very consistent on this issue.

For those who don't want a technical outlook, here's the main thing. By the end of October and early November, expect a very cold air mass to move into the region, quite possibly bringing the chance for our first snowflakes, and likely on the tail end of a monstrous storm system.

Light blue represents below normal temperatures and dark blue represents much below normal temperatures. This will likely take place anywhere in the timeframe from October 23-November 3.