Winter weather can be fickle around here
One year being brutal, another being mild.
Sometimes, like last year, it starts out very cold and snowy, then suddenly warms up for the entire month of January.
So what is it going to be this year?
Official records are kept at the South Bend Regional Airport, but of course the weather can vary even across South Bend, or into Mishawaka, Elkhart and Berrien County.
Huge variations usually occur from one side of Michiana to the other.
Lake Michigan plays a role, obviously, but there are several factors that effect our winter pattern, and none of them are anywhere near here.
The first factor I'm going to look at is El Nino.
It is a strip of warmer than normal water along the equator from South America to the central Pacific.
Typically, El Nino increases the Jet Stream that slams storms into the Western United States.
A strong El Nino can flood the entire country with warm air, including here.
But this is NOT a strong El Nino
In fact, it is weak to barely moderate right now.
something that concerns me here, though.
The pocket of colder than normal water in the north Pacific
This could actually increase the flow to where it mimics a strong El Nino.
We will see.
But, overall the effect of a weak to moderate El Nino on Michiana is for a slightly colder and drier winter.
The second factor is the North Atlantic Oscillation.
This plays a huge role in our winter weather, but I will admit it is not something we forecast very well yet.
This year, though, there is a pocket of unusually warm water across the entire North Atlantic.
That produces high pressure that can slow, or block, the flow of storms across the Atlantic.
To me this suggests that there could be several spells this winter where the Jet Stream buckles and pulls Arctic air our way.
The effect on Michiana would be colder air, and perhaps an increase in lake-effect snow, NOT system snow.
The third factor I want to visit is the current snow-cover to our north.
There is more snow than normal right now across most of central and western Canada, which allows cold air to increase
Of course that cold air does not have to come our way, but it makes it a bit more likely.
The effect on us can sometimes be minimal, but it sustains the cold air that does come our way.
With all of that in mind, here is my Forecast for the Winter of 2006/2007:
I think that temperatures will end up averaging slightly colder than normal, by about 1 degree or so from December through February.
As for snow, I am forecasting 75" of the white stuff officially, which is almost normal, just an inch and a half shy.