While the eastern U.S. shivers under the effects of Winter Storm Stella and its frigid aftermath, the Southwest is in the grips of a March heat wave.

Cities such as Phoenix, Las Vegas and Palm Springs could all set record high temperatures this week, according to AccuWeather.

On Monday, the Phoenix area hit 90 degrees for the first time this year, the National Weather Service said, when the temperature shot up to 92. That's more than two weeks ahead of the city's normal first 90-degree reading.

Phoenix should see several days with highs in the lower to middle 90s this week.

Saturday is expected to be the warmest day of the week in Phoenix, the weather service predicted. Saturday's forecast high temperature of 96 degrees in Phoenix would break the old record of 94. The “normal” high temperature in Phoenix on Saturday is just 77 degrees.

People "headed to Major League Baseball spring training games in Arizona will want to wear sunglasses and a hat, apply sunscreen and drink plenty of water," AccuWeather said.

Palm Springs, Calif., should also soar into the low to mid-90s while highs will flirt with the 90-degree mark in Las Vegas, AccuWeather said. Downtown Los Angeles should see highs in the upper 80s.

The heat is courtesy of a large area of high pressure centered over the Southwest. Air sinks under high pressure, which prevents clouds and rain from forming.

Meanwhile, on the other coast ( ... see below)