April 29, 2024

Polar Vortex Unleashed Winter Weather Whiplash in the US

In the very first few days of January 2023, conditions altered significantly. Rather of unseasonable cold, much of the exact same areas experienced unusual heat. With temperatures running 20-30 degrees Fahrenheit higher than regular in the eastern U.S., spring-like weather broke temperature level records in numerous states. Among the places that set brand-new temperature level records were St. Louis, Missouri; Raleigh, North Carolina; Paducah, Kentucky; Mount Pocono, Pennsylvania; Atlanta, Georgia; Georgetown, Delaware; and Dulles, Virginia.

The animation above programs surface area air temperature across part of the Northern Hemisphere, including North America, for December 2022 and the very first few days of January 2023. The darkest reds reveal locations with the hottest surface temperature levels; blue locations show areas with the least expensive surface temperatures.
A warm air mass from the west coast of Africa shattered thousands of temperature level records across Europe, The Washington Posts Capital Weather Gang reported.

The eastern and main United States experienced winter season weather condition whiplash in December 2022 and January 2023, with possible contributions from the polar vortex. This led to a rapid shift from incredibly cold temperature levels to tape-record high temperature levels in North America.
The configuration of the polar vortex may have contributed in releasing bitter cold followed by record heat in North America.
December 2022 and January 2023 brought winter season weather condition whiplash to the eastern and central United States.
In late December, numerous Americans reached for cold-weather gear as a blast of uncommonly cold Arctic air poured south and sustained a travel nightmare around Christmas. The vast cold front left its mark on the Southeast as well, where the cold air helped fuel twisters, interrupted power products, and strained water systems.

With temperatures running 20-30 degrees Fahrenheit higher than normal in the eastern U.S., spring-like weather broke temperature level records in several states. Among the locations that set new temperature records were St. Louis, Missouri; Raleigh, North Carolina; Paducah, Kentucky; Mount Pocono, Pennsylvania; Atlanta, Georgia; Georgetown, Delaware; and Dulles, Virginia.

The animation above shows surface air temperature level across part of the Northern Hemisphere, consisting of North America, for December 2022 and the very first few days of January 2023. It was produced by integrating satellite observations with temperatures calculated by a version of the Goddard Earth Observing System (GEOS) international model, which uses mathematical formulas to represent physical procedures in the atmosphere. The darkest reds show locations with the hottest surface area temperatures; blue areas reveal locations with the most affordable surface area temperatures.
The short pulses reflect day-to-day daytime warming and nighttime cooling, however the spread of cold Arctic air south over much of the U.S. ended up being obvious towards the end of the month, particularly in the week prior to Christmas. Due to the fact that water more quickly maintains heat and maintains a more consistent temperature, the everyday cycle is less visible over water. Lots of locations saw temperature swings that ranged from approximately 20 ° C to 40 ° C( 36 ° F to 72 ° F) in between the heights of the cold spell on December 23 and the warm spell on December 30
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Continental United States surface temperature level on December 23 and December 30, 2022.
The very first week of 2023 likewise brought record-breaking warmth to Europe. A warm air mass from the west coast of Africa shattered thousands of temperature level records throughout Europe, The Washington Posts Capital Weather Gang reported. On New Years Day, at least seven countries saw their hottest January weather condition on record.
” Theres a common thread linking all of these temperature level extremes,” stated Judah Cohen, a visiting scientist at the Massachusetts Institute of Technology and a forecaster with Atmospheric and Environmental Research (AER).
” In December, we saw an elongation and weakening of the dizzying polar vortex in the Arctic– the band of strong westerly winds that flow in between about 10 to 30 miles (16 to 48 kilometers) above the North Pole in winter season,” Cohen stated. When the polar vortex is strong and circular, it keeps cold air repressed over the Arctic; when it damages and elongates, the jet stream in the troposphere likewise tends to lengthen southward and cold air from the Arctic can spill down into the midlatitudes.
” But when the polar vortex stretches, it does not remain in that configuration for long,” Cohen added. “Like an elastic band, it tends to snap back into a circular shape, generally within about a week.” The snapback in early 2023 was a crucial part of the reason that the jet stream straightened and why warmer air masses from equatorial regions warmed the eastern U.S. and Europe, according to Cohen.
Theres likewise a more complex question that Cohen and other climatic scientists who specialize in the stratosphere are investigating with growing interest: are these stratospheric polar vortex interruption events– these stretching events– becoming more frequent over time and, if so, why?
After examining decades of metrological information utilizing the MERRA-2 weather condition reanalysis design kept by NASAs Global Modeling and Assimilation Office (GMAO), Cohen and colleagues think that stretched polar vortex occasions have ended up being more typical because 1980. In a research study published in Science in 2021, Cohen and associates linked declines in Arctic sea ice in the Barents and Kara Sea and increases in snowfall in Siberia– both of which are connected to environment change– with a boost in polar vortex interruptions and cold spells in the midlatitudes.
” Not everybody concurs with us. Its still objected to science, but I am confident that well see more and more examples of these extending events in the stratosphere followed quickly after by cold snaps in the midlatitudes as the Arctic climate warms and changes,” stated Cohen. “The extending of the polar vortex we saw in December 2022 certainly fits that pattern.”.
NASA Earth Observatory video and images by Joshua Stevens, utilizing GEOS-5 data from the Global Modeling and Assimilation Office at NASA GSFC.