Wednesday , May 12 2021

The warmer, more humid than the usual winter, headed by much of the United States

Just over half of the United States does not have to fear an exceptionally cold and frozen winter in the coming months; On the other hand, they will probably experience a warmer and more humid winter than usual, according to the National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center.

In the next three months – December, January and February – the west coast, mountain states and parts of the Midwest and Northeast (though not New York or Boston) are predicted to have temperatures above normal for The season, as well as The rise in precipitation (which means rain and snow) announced on Tuesday, November 15, the Climate Prediction Center.

Warm and humid winter is due, in part, to weather patterns such as El Niño and decadane changes in oceanic patterns, as well as climate change, said Stephen Baxter, a meteorologist and seasonal precursor at the NOAA Climate Prediction Center. [Winter Wonderland: Images of Stunning Snowy Landscapes]

During the press conference, Baxter presented for the first time the weather forecasts for December, which are shown below. Areas that are red, orange, and yellow are predicted for winter temperatures higher than normal, he said. The blue region that encompasses the Great Lakes region is expected to be cooler than usual. Meanwhile, it is expected that the areas of white color in the United States have typical winter temperatures.

Perspectives for December 2018 for the average temperature (left) and precipitation (right).

Perspectives for December 2018 for the average temperature (left) and precipitation (right).

Credit: NOAA

Regarding the December precipitations (the map to the right), the green fringes on parts of California, the states of the Mountain and the Southeast indicate precipitations above normal, while the yellow patches that go diagonally from Texas to Maine show that those regions They will probably receive less precipitation than average.

The temperature outlook for December-January-February is a bit different. Note how: on the map shown below, temperatures above the average still cover Alaska and much of the West and Midwest of the United States, but the expected cold spot disappears on the Great Lakes area.

The average of December, January and February of temperature (left) and precipitation (right).

The average of December, January and February of temperature (left) and precipitation (right).

Credit: NOAA

Prospects for three-month precipitation show a different story. It is expected that the lowest level in the United States will get more than average rainfall, while the Midwest and Great Lakes regions will get precipitations lower than normal.

It seems that El Niño is partly responsible for the hottest temperatures on the west coast. The Child occurs when the equatorial Pacific Ocean is darkened, which in turn inclines hot water and humid air to the east facing America. The Niño also tends to lead to the eastern extension of the water stream of Southeast Japan through the Pacific basin and a low pressure system in the Pacific Northwest, Baxter said.

All these factors tend to "lead to anomalous hot air convection in western United States and southern Alaska," Baxter said. (In other words, it has hot air where it normally does not.) "And then you tend to have less cold air intrusions there. You also tend to have more storm activity across the southern US and that's how it increased the Storm there. "

Climate change also plays an important role in this winter climate, although it may be difficult to know how much, Baxter said. This is because so many factors influence the climate, such as the increase in greenhouse gas emissions and decadent changes in oceanic patterns, so it can be a challenge to determine which signals come from where.

"Part of the challenge is to unravel these things," Baxter said. "The climate is now more than the fixed base period of 30 years we use … and much of it is long-term climate change."

Instead of taking the average of the last 30 years, climatologists are finding that they can get a more accurate picture of the current climate by taking an average of only the last 15 years. And, according to NOAA and NASA, the five hottest recorded years occurred in 2010, while the 10 hotest registered years have taken place since 1998, Climate Central reported earlier this year.

Originally Posted in Live science.

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