I want to start this evening’s blog with a screen shot of the forecast for the next 5 days. While this is for Westbrook, it gives you a great idea of the stunning close to meteorological summer and start to September.

Meteorological summer represents the end of the warmest quarter of the year, and next up is the transitional season of autumn. The summer of 2015 will go down as a somewhat drier than average and fairly typical in terms of heat. Across far northern Maine, this has been one of the warmest Augusts on record.

Summer in September
This year, like last, is setting up to be very warm in September. There have been several Septembers over the past 15 years where Portland and other areas of southern Maine have made it into the 90s.

The image below shows some past Septembers where Portland’s temperature has reached 90 degrees. Notice there are many years since the turn of the century where 90 has been reached in September.

Bermuda High

September 2007 was a very month month. Notice how often Portland was in the 80s and 90s!

Over the next 10 to 14 days, high pressure off the coast of the southeastern U.S. is going to keep New England in a very summery pattern. While there will be some days that are cooler than others, the overall pictures is summer, not fall.

I expect several opportunities to reach 90 degrees, at least inland, between the final day of August and the first two weeks of September. Whether we see a heat wave or not is still questionable and not easily achieved in the 9th month, but with the current atmospheric set-up, it isn’t out of the question. The map below shows one model’s predictions for temperature during the first half of September.

You should definitely take the mindset of summer until further notice. Air conditioners not sweatshirts are going to be needed for a while longer. For anyone sitting in school buildings without air conditioning, there will definitely be a few tough days ahead.

Warm Fall, Cold Winter?
Many prognosticators are already writing or talking about the upcoming winter. The Farmer’s Almanac is predicting a blockbuster winter here in New England. There are a lot of computer models out there to help with the upcoming winter forecast.

Long-range forecasting is so tricky. A few anomalous days or weeks can throw off an entire forecast. While last winter was certainly amazing in terms of the extent of the cold and snow, we did make it through about half the winter with very little snow.

December brought many days of warmth and quite of a bit of rain. Yes, the 80 plus inches of snow that fell in about 8 weeks was unprecedented in modern times, but we had reached the third week in January without much snow at all. The snow also stopped falling by the third week in March, somewhat earlier than other years. Would you rather have seen 6 inches of snow every week for 18 weeks?

El Nino Winter
El Nino continues to come on strong, and will definitely be a major player in our winter weather. Some years with strong El Nino’s have brought significantly less snow than we would typically experience.

A very warm pool of water off the Pacific Northwest coast and warmer than average waters in the north Atlantic will also influence the day to day weather here in New England. The two maps below show these pools of warmth. The first map is for the first part of winter, the second takes us into the first part of spring. Notice the ocean waters becoming less warm off the coast of the Pacific Northwest. This will no doubt change the pattern moving into next summer.

One thing the models are showing is a slower start to winter again. In other words our mild fall will likely linger into the first part of winter. This doesn’t mean a repeat of last winter. The ocean waters across the globe aren’t the same as last year and no two winters are ever exactly alike.

The Past Helps Predict The Future
The map below shows what the global ocean waters looked like during the winter of 1982-83. I like that winter as one of the analogs to look at for this winter.

Portland received only about 45 inches of snow that season.

This is just some of my latest thinking about the fall and winter seasons. Over the coming weeks I’ll share more of my thoughts and the thoughts of others. Follow me on Twitter @growingwisdom for more weather details and to ask any questions or give comments.

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