Why has it been so warm lately?

Since November, we have been seeing more warmer weather than usual. High temperatures, reaching the 60s and even touching 70. There have been days that have been little cold. But more days that have been much warmer. There are number of reasons why we have be warm of late. But they require a knowledge of meteorology (study of weather), to to better understand them all. So I will just explain the top reason why it hasn't gotten very cold here yet. As simply as I can.

Our weather during the late fall and winter seasons, is often influenced by a weather pattern  called the North Atlantic Oscilation (NAO).  There are two phases of the NAO. The first phase is negative. The second phase is positive. Each phase has a different influence on weather.

The negative phase of the NAO, is when there a large high pressure system near Greenland, causing the jetstream to dive over the Eastern United States. This results in more colder days and snowstorms for the New York city area. This phase is also called the Greenland Block. Which you might hear the weathermen on tv talk about, sometimes.

The positive phase of the NAO, is when there is large low pressure system over the North Atlantic, that causing the jetstream to run further north over the Northern United States. This keeps the cold air up in Canada, resulting in more warmer days and rainstorms for the NYC area.

You may of guessed it. But we are have been the positive NAO phase! So how long will this continue?  I don't know yet. So in the meantime, enjoy the warmer weather!

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