Truth Strikes: Debunking Biggest Weather Myths

Early-season heat is setting records once again in the Southwest and is spreading into the Pacific Northwest, where it will last through Mother's Day weekend.

Once again, the jet stream has bulged northward – into a configuration known as an upper-level ridge of high pressure – over the western United States, creating a dome of hot air over the region.

(MORE: How Early in the Year Have 90-Degree Temperatures Happened in Your Region?)

There's already been some notable heat this week in the West.

El Paso, Texas, soared to 100 degrees Thursday, the earliest in the season they had ever done so, and one month earlier than their first 100-degree high last year.

Palm Springs, California, reached 110 degrees Thursday, a daily record. They have seen triple-digit highs 13 of the past 15 days since April 22.

Phoenix (106 degrees) tied its daily record high on Wednesday. A new daily record high of 106 degrees was set in Tucson, Arizona, on Wednesday. Las Vegas had its first 100-degree day of the year on Wednesday, when a high of 101 degrees was recorded at McCarran International Airport.

Juneau, Alaska, recorded its first 70-degree high of the season Friday, as the eastern U.S. shivered.

(MORE: May 2020 Temperature Outlook)

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