Outlook for winter

The Climate Prediction Center has issued its winter outlook for the nation and it has implications for our Suncoast winter. The driving force in the latest outlook is the lack of any driving force.  For us on the Suncoast one of the most powerful winter influences is the presence of an El Nino or La Nina, the warm or cold swings in the water temperatures of the tropical Pacific.  The presence of these warmer than normal or colder than normal cycles that occur every few years has a profound effect on the motion of the winter jet stream and patterns of winter storm motion. 

 This year the Climate Prediction Center is forecasting the absence of either warm or cold El Nino or La Nina. This is the so called neutral phase and it is expected to last into the spring.  However, the fact that we don’t have a strong driving weather feature  does allow us to make some projections.

 Our weather pattern this winter should feature more variable temperatures swings as the jet stream will not be constrained by an El Nino or La Nina.  This will allow the jet to wag north and south over the three month winter outlook.  This should lead to a greater warm/cold roller coaster this winter.

Winter temperatures

That said, the Florida Climate Center reports that the state will have an increased risk of a damaging freeze this year.  This is due to the same reasoning I mentioned above for our temperature swings.  Without an El Nino or La Nina to block Arctic air masses the cold Canadian air is, at times, free to plunge into Florida.  The Climate Center states that  most of the severe “impact” freezes over the last one hundred years have occurred in neutral phase years.

Winter chance for hard freeze.

Winter tends to be drier anyway and the forecast holds true to climatology. With the southeast down about 50% on seasonal rainfall and the Suncoast also dry for the month, the outlook calls for this to continue into spring. 

Winter rain forecast

So the winter will be characterized by weather swings and no clear signal of abnormally colder, wetter, or drier conditions.  As Mike Halpert , the acting director of the Climate Prediction Center, stated in a NOAA press release “It’s a challenge to produce a long-term winter forecast with out the climate pattern of an El Nino or a La Nina in place…Without this strong seasonal influence, winter weather is often affected by short-term climate patterns, such as Arctic Oscillation, that are not predictable beyond a week or two. So it’s important to pay attention to your local daily weather forecast.”  I second that.

John Scalzi