Record or near-record temperatures continued across much of the United Sates this week. Folks in Chicago and New York City were able to have a picnic during the lunch hour. Seventy-one locations in the Plains and Northeast set records Tuesday, including 81 degrees in Omaha. The cause of the warmth is related to three major factors. The weather is so warm that the famed cherry blossoms in the U.S. capital will reach their peak bloom earlier than expected.
One of the causes is the Madden-Julian Oscillation (MJO), a large-scale disturbance that moves east around the Earth's equator over a period of 30-60 days, influencing rainfall and weather patterns around the world. La Nina and the Arctic Oscillation are factors as well. The La Niña climate pattern is a cooling of tropical ocean water in the Pacific. The Arctic Oscillation is a swinging of high and low atmospheric pressure over the Arctic. The warm conditions will continue across much of the area for the next week.