Wild fires in September? Sure. Especially if you've had rain most of the Summer and it suddenly shuts off. If you read our blog regularly, you know that I love long range forecasting. Following the sun and its' cycles, what phase the oceans are in, etc., is fun to me. Recognizing the trend, seeing if that trend will continue or change, and specifically what that trend will mean for our local weather is where I can tie it all together. Sometimes the particular thing that impacts the trend is subtle. Other times, it is so clear cut that it seems just plain easy. Unfortunately, this upcoming Fall and Winter seems pretty easy to figure out. La Nina is back and has been for the past couple months. It continues to strengthen and this is not a good sign for Southern and Eastern Colorado.
All of that blue and purple across the central Pacific Ocean means that the current sea surface temperatures are below normal. This is consistent with La Nina and the upper pattern has shown some signs of reflecting this La Nina trend. Remember all that nice rain we had in July and early August? That has shut off completely. I don't think it is coming back anytime soon...
The prevailing pattern during a La Nina is one of frequent frontal passages, usually accompanied by a strong north to northwest wind. That usually keeps the heavy snow away from much of the Front Range of Colorado. It does mean good snow for the central and northern mountains, but keeps areas immediately east dry and windy. Now this doesn't mean that we will be snow free or not see an occasional snowstorm or two, but the frequency of heavy snow is greatly reduced. So, if you were expecting big things this Winter in terms of snow, I think the Winter of 2010-11 will disappoint you. Will continue to update you on the progress of La Nina and get more specific with the forecast in the coming weeks.
Chief Meteorologist Brian Bledsoe