It’s the time of year when lovers of cold and snow start to get excited as visions of blizzards and bitterly cold temps dance in their heads. “What kind of winter will we have?” is THE most asked question I get and that usually starts in the summer. It’s time to give you an answer with the 2011-2012 Winter Forecast.
Before we get into the nuts and bolts of the forecast, let’s talk about where we’ve been and where we are.
We’re in the midst of our coldest and snowiest winters since the late 1970s. That’s the last time we put together back to back average winter temps below 32 degrees and the last time we recorded 20″+ snowfall in back to back winters.
Can we make it 3 in a row of colder and snowier than normal? The short answer is yes. Let’s take a look at why I think a trifecta of snow and cold is likely.
The map below shows the current state of the oceans that can have a major impact on the weather across the country.
– The Atlantic ocean shows a configuration of colder and warmer water that should favor a -North Atlantic Oscillation (NAO). This would favor blocking high pressure over Greenland and helps to force cold air from Canada south into the states.
– We continue to see a strong – Pacific Decadal Oscillation (PDO). This features colder than normal water temps along the west coast of the U.S. into the northern Pacific near Alaska. We have been in a -PDO phase for the past several years.
– The biggest driver is sitting near the equatorial Pacific Ocean. La Nina is alive and well for the second fall and winter in a row. This is when the waters in this area run colder than normal over a wide region. The forecast models all show those temp anomalies dropping into the winter months:
I look at all of that information(and other variables) and then check for past years that had similar features to what we’re seeing now and then narrow the list. This allows me see how the following winters for those years turned out and that can give me clues into how this winter may fair.
I also match those years to see if any of them match up with the actual weather we’re experiencing around here. Of all the years I’ve looked at, 1950 seems to be the closest match to the actual weather and the global indicies. That year went on to feature a cold and snowy winter for Kentucky and included several big events. It is important to note that no two winters are ever alike and never play out exactly the same way.
One final thing to take into consideration is the fall snow cover across the Northern Hemisphere. The greater the snow cover, the better the chance the winter air will be colder than normal. Let’s call it the cryosphere effect. Snow cover right now is MUCH above normal:
-Odds favor another colder and snowier than normal winter for Lexington and much of Kentucky.
– I expect our temps to average one to three degress below normal for much of the state. Here’s the breakdown:
– December and Janurary are likely to see the coldest departures from normal with moderation to above normal possible for February. Wild temp swings are a good bet and I expect a few severe cold shots that will take our temps below zero.
– Snowfall should average above normal for the entire state. Lexington averages around 14″ of snow per winter and this winter should see totals in the 20″-25″ range. Here’s what i’m expecting for the entire state:
– How do we get to those totals? There are several different snow events I will be watching for. This is a year that should feature several “clippers” diving in from the northwest. These are generally light snow producers. The Great Lakes are much warmer than normal and this means a likely increase in snow showers and squalls during a northwesterly wind setup.
– I see other options that can give us a more substantial snowfall. The fall pattern strongly argues for a couple of big winter storms to impact the state. We have seen several big closed upper level lows parking themselves across the Ohio Valley this fall. If we can get this type of setup this winter:
Then we can get a blockbuster storm somehwere across the state. That is certainly not set in stone, but the fall pattern certainly suggests something like that being possible.
There you have it… the 2011-2012 Winter Forecast. Here’s hoping you get as much or as little snow as your heart desires. The blog will be here with you each and every step of the way with frequent updates each and every day.
Feel free to leave your thoughts on the winter ahead and keep checking back for daily updates. Happy snow tracking and take care.