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  2. Polar vortex set to freeze the U.S. as far as the Deep South

    www.aol.com/polar-vortex-set-freeze-u-013449946.html

    During the winter months and when the jet stream allows, this cold air can drop farther down into lower latitudes like in the United States. This is forecast to happen as soon as this weekend.

  3. Jet stream - Wikipedia

    en.wikipedia.org/wiki/Jet_stream

    The northern polar jet stream is the most important one for aviation and weather forecasting, as it is much stronger and at a much lower altitude than the subtropical jet streams and also covers many countries in the northern hemisphere, [38] while the southern polar jet stream mostly circles Antarctica and sometimes the southern tip of South ...

  4. Pacific–North American teleconnection pattern - Wikipedia

    en.wikipedia.org/wiki/Pacific–North_American...

    An example of positive PNA (left) and negative PNA (right), based on anomalies in the geopotential height of the 500 hPa pressure level. The Pacific–North American teleconnection pattern (PNA) is a large-scale weather pattern with two modes, denoted positive and negative, and which relates the atmospheric circulation pattern over the North Pacific Ocean with the one over the North American ...

  5. How The Start Of February Will Be Different Than January ...

    www.aol.com/start-february-different-january...

    The yellow and orange shadings on the map below show where temperatures are forecast to be above average on Sunday. ... the jet stream has taken repeated sharp southward plunges over the central ...

  6. SIGWX - Wikipedia

    en.wikipedia.org/wiki/SIGWX

    The SIGWX charts only show the forecast for the specific hour, however it is common place for parameters such as the JetStream, CAT & CB to be interpreted +/- 3 hours of the chart validity time. . Prognoses are typically prepared for two ranges of heights: SWH - High Level SIGWX (Flight level 250-630) SWM - Medium Level SIGWX (Flight level 100-450)

  7. Weather map - Wikipedia

    en.wikipedia.org/wiki/Weather_map

    Such maps have been in use since the mid-19th century and are used for research and weather forecasting purposes. Maps using isotherms show temperature gradients, [2] which can help locate weather fronts. Isotach maps, analyzing lines of equal wind speed, [3] on a constant pressure surface of 300 or 250 hPa show where the jet stream is located.

  8. A disjointed jet stream has some climate scientists spooked - AOL

    www.aol.com/scorching-heat-canada-wildfires...

    The jet stream, a ribbon of air that encircles the Northern Hemisphere at high altitudes, drives pressure changes that determine weather across North America. The jet stream’s wavy pattern ...

  9. Trough (meteorology) - Wikipedia

    en.wikipedia.org/wiki/Trough_(meteorology)

    A lee trough, also known as a dynamic trough, is "A pressure trough formed on the lee side of a mountain range in situations where the wind is blowing with a substantial component across the mountain ridge; often seen on United States weather maps east of the Rocky Mountains, and sometimes east of the Appalachians, where it is less pronounced."