We all know it was a LA NADA winter last year in the NJ NY CT LI area so the big question is will history repeat itself ? The answer is NO. We have looked over many early factors and what happen last winter was about as rare as it gets.
We had a pretty warm phase of the La Nina and an unusually +AO. You are probably asking what is a +AO. No it's not some grade or element of the periodic table it's The Arctic Oscillation.
Last Winter the cold stayed NorthThis Winter we see shots of cold
Let's take a look at some NYC Metro Winter Facts and Stats before we get into the actual outlook for 2012-2013. We had a feast of snow two winters in a row before the LA NADA winter last season.
Take a look at the snow decline the last 150 years. This is due to the growth in NYC as it becomes a bigger heat island and to a degree a climate change cycle we are in right now. You can also see on the light blue dots it's rare to go back to back winters under 10" at Central Park.
THE 2012-2013 NYC METRO WINTER OUTLOOK
El Nino is now not a factor so the big three factors are:
1. NAO Index 45%
2. AO Index 35%
3. Snow Cover in Canada & USA 20%
3 BIG FACTORS TO CARVE OUT THE WINTER OF 2012-2013
If we sit here for the winter ahead this is good news for the snow lovers in the NYC area including NJ LI NY CT. This will allow for good moisture but with not all the warmth of a full blow El Nino in the Northeast. But wait one must not forecast but a weak El Nino alone.
I Know it's very early to be looking at the NAO (North American Oscillation but looking over the trend of last winter and how the Weak El Nino and decent -AO look to be playing out we'll see a lean toward the Negative side on the NAO index. This means a better than 50% chance of at least (2) 4"+ snowstorms in NYC Metro Area.
Last year this meter sat on the Positive for most of the winter. We had a few short periods on the Negative side but the lack of any real cross polar influence led to not only the warmest winter on record for most of North America but some of the least amount of snow cover from Northern Canada to the USA.
We see a return to the cross polar flow...not the coldest winter ahead of us but enough to pop with a -NAO and a few good shots of southern moisture.
Slight error on that graph. NYC got 7.9" last winter not 2.7". But its still amazing how NYC got 7.9" meanwhile I almost doubled it at 13" just 1 hour outside the heat Island in SWCT by the coast. NYC Snow total Source: http://www.erh.noaa.gov/okx/climate/records/monthseasonsnowfall.html