Those who noticed a lack of humidity, along with a rise in whitecaps this July, were right.
All of our weather comes FROM somewhere. In a normal summer, we get weather mostly from the southwest. That brings heat (or warmth) and humidity up from the Gulf of Mexico, serving the whole eastern half of the nation along the way. On those warm days it's not uncommon for a lake breeze to kick in, on the open lake, after a calm morning. This breeze is usually from the southeast. It may become a strong "sundown wind" late in the day, and will die off to calm after sunset.
This summer, we had a lot of air flow FROM Canada. That's from the northwest. Our normal air flow here is from that direction in all but the summer months -- usually July and August. Our average wind direction is from the Southeast in July and August. Usually, the "lake breeze" and "sundown wind" account for that. It can also be an extension of any seabreeze that is strong enough to reach Alton. If any ocean influence is strong enough to get there, it has a free shot at Center Harbor via the water.
In May and June of this year our average wind direction was from the southeast, which is unusual. It wasn't fair-weather breezes, though. Rainy weather often produces wind from that direction. May and June were rainy here.
July produced an average wind direction from the northwest -- out of Canada. That is very unusual. Air coming from that direction is dry, having traveled a great distance over land without crossing any oceans. We don't get humidity from Canada; we get it from the Gulf of Mexico.
Our humidity this July averaged 69 percent, as compared with last July at 71 percent. July 2008 and 2009 both averaged 80 percent.
Humidity drives the lake water temperature up, and it will try to achieve whatever the air temperature is. The lake loses a lot of heat to surface evaporation into the air, especially when windy. The drier (and faster) the air is, the more evaporation it can take from the surface of the lake. If the air is humid and calm, the lake cannot cool by "sweating" into the air. This year we only reached a water temperature of 76 F.
Those of you who've noticed the shortening summers are also right. The "rainy season" is the kind of weather we get when the summer air is trying to move in, and the cold air of winter is still holding on. That season was traditionally in April ("April showers bring May flowers") but the past few years the rainy season has been ruining Bike Week a lot.
The rainy season always ends with the summertime air winning. At the end of the season we start seeing more frequent showers and thunderstorms as the cold air starts coming back. There are still warm days but they become fewer and farther between. We get the back & forth temperature scheme until the wintertime air wins.
As for winter forecasts, even November is too early to make a winter prediction in New England. One could predict the overall (national/international) weather pattern for winter, right now, in August. But New England's weather can very greatly from the overall pattern. The rest of the country can be partaking in a hemisphere-wide weather pattern while New England experiences a local exception whose reasons cannot be determined until it's already happening.
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