2012-2013 Winter Prediction Part II

I have some animations below what pattern we are going towards. These plots represent an average of several years over a 60 year time interval (1950-2010). I used some criteria to choose my years.

1)An easterly oriented El Nino or neutral ENSO, with a positive Trans-Nino-Index (greater than 0)
2)Nino 1+2 value less than or equal to 1.5, and greater than or equal to -0.25
3)No Nino value (Nino 1+2, Nino 3, Nino 4, Nino 3.4) may exceed +2, or fall below -1
4)A weak negative Pacific Decadal Oscillation (greater than -0.5) to a moderately strong positive PDO (less than +1.5).
5)Months covered are December, January, February, and March

So out of all the criteria, I am left with 36 months worth of data. For my ideal scenario, which has a tighter range of acceptable values, I only have 17 months fitting the bill. I will have two types of animations below: one for the wider criteria and one for the narrower one.

Wind Vectors for wide criteria

Wind Vectors, small criteria

Vector wind, zoomed in. A lot of our storms will skirt off the coast to start our winter.

Geopotential height anomalies, wide criteria

Geopotential height anomalies, small criteria. This points to a slow start to our winter.

Vorticity for wide criteria. Vorticity measures the spin in the atmosphere. What we see is a very active Alberta Clipper track and a developing subtropical track, but we are not finding our vorticity maximum riding along the east coast until late January/early February.

Hang on, notice the persistence of that vorticity signature over the Midwest? This is actually a diminished Colorado Low storm track. I don't think lee cyclogenesis east of Colorado is the reason for this but rather is a deepened trough on the Alberta Clipper storm track or an ascending subtropical branch instead (FAR more likely the ascending branch idea). This is dropping into the Midwest, and these storms are likely to be ice storm producing rather than just pure snow in nature. The storm here is a wild card: it may end up following the track farther north or will degenerate west of the Appalachian Mountains, only to reform east of the Carolinas. I don't see this being a primary track for any month but will be a consistent secondary track during all winter months.

According to the winters MOST like this predicted one (on a record from 1950-2012), the average snow total was 29" of snow for Boone, with a range from 18" to 56" of snow. With the wider margin the average snowfall for this kind of winter would be 33.3" of snow, with a range from 18" to 71". But, the blizzard of 93 heavily skewed that 71" measurement. Most notably, I had quite a few of these winters hover around a very tight gradient. My 25th and 75th percentile were 25" to 36".

Prediction: this winter will have above normal precipitation with near normal to slightly below normal temperatures, with a very slow start to our winter. Due to insufficient synergy of the polar jet and the subtropical jet until the last half of winter, snow totals for Boone, NC will hover around the 25-30" mark, +/- 5" of snow. That is still a wide gradient but we are still several months away from winter.