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Thawing in Alaska, freezing in the Great Lakes: U.S. had world’s most extreme temperatures in November

November 2014 temperature differences from average (University of Alabama-Huntsville, adapted by CWG)

Compared to average, the eastern half of North America was colder than anywhere else in the world during November, according to an analysis of satellite temperature measurements from the University of Alabama-Huntsville (UAH). Meanwhile, the warmest temperatures in the world (again, compared to average) were in the vicinity of northern Alaska.

“[T]he coldest place in Earth’s atmosphere in November was in northwestern Wisconsin, just outside the town of Cable, where temperatures were as much as 3.29 C (about 5.92 degrees Fahrenheit) colder than seasonal norms,” the UAH analysis says. “[T]he warmest departure from average in November was in the Beaufort Sea off the northern coast of Alaska. Temperatures there were as much as 5.20 C (about 9.36 degrees Fahrenheit) warmer than seasonal norms.”

An incredible see-saw jet stream pattern set up these opposing temperature extremes. Over Alaska, a massive ridge of high pressure caused the jet stream to bulge to its north allowing relatively mild air to flood the normally frigid state. The jet stream then buckled, crashing southeastward over the eastern half of North America and unleashing bitter Arctic air.

This pattern has set up repeatedly during the 2014 calendar year, as we have documented in previous posts: Snowed under and frozen over: U.S. weather is off the rails, but why?U.S. weather in 2014 is more bi-Polar than ever |Eastern U.S.: Coldest spot on Earth so far in 2014 | The eastern United States: A lonely cold pocket on a feverish planet

As chilly as the eastern U.S. was, UAH reports that  it was the second warmest November on record in its 36-year record for the globe as a whole, fitting into a long-term warming trend.

UAH notes that its record shows the Earth has warmed at a rate of about 0.25 F (or 0.14 C) degrees per decade since satellite data became available for analysis, but with significant regional variability.

Since 1978, the fastest warming globally has occurred in the Arctic (warming at a rate of 0.88 F degrees per decade) while pockets of East Antarctica have actually cooled.  The rate of warming over the Lower 48? About 0.4 degrees F per decade which works out to 1.43 degrees F overall since 1978.