NOAA's Climate Scene Investigators analyzed why the mid-Atlantic region had record-setting snowstorms this winter. The team looked for but found no human "fingerprints" on the severe weather. Instead, they fingered two naturally occurring climate patterns as co-conspirators in the case.

In May and June each year, speculation about the coming of the monsoon fills newspapers and conversations across India. Everyone is concerned about if, when, and how much rain will arrive. But none have more at stake than India’s over 100 million farming households.

The Pacific-North American teleconnection pattern influences regional weather by affecting the strength and location of the East Asian jet stream, and subsequently, the weather it delivers to North America.

The Arctic Oscillation (AO) refers to an atmospheric circulation pattern over the mid-to-high latitudes of the Northern Hemisphere. The most obvious reflection of the phase of this oscillation is the north-to-south location of the storm-steering, mid-latitude jet stream.

Over the span of days or weeks, the strength of surface air pressure over the North Atlantic seesaws between Iceland and the Azores Islands. The shifting pressure reflects changes in atmospheric circulation that have a big impact on mid-latitude weather in the U.S. and Europe. 

Guest blogger Amy Butler explains how changes in the stratospheric polar vortex can influence the "usual" effects of El Niño on the climate in the Northern Hemisphere.

Where are my El Niño impacts?!

Was El Niño to blame for the above-average temperatures during November and December 2015?  As always, the answer is not that simple.  

“El Niño is Strong!” “No, it’s Moderate!” “But the [insert your favorite ENSO indicator here] is the largest it’s been since the El Niño of 1997-98!”

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