Historic March heat wave heading for Desert Southwest

YUMA, Ariz. (KYMA) - A historic early-season heat wave is building across the Desert Southwest, and it's expected to push temperatures in Yuma and the Imperial Valley into the triple digits later this week.

According to the National Weather Service, strong high pressure settling over the region will rapidly heat up the lower deserts beginning midweek.

While highs Monday are already climbing into the mid-90s, temperatures will continue to rise Tuesday with some areas of the Lower Colorado River Valley approaching 100 degrees for the first time this year.

By Wednesday, the heat intensifies. Forecasters expect temperatures across Yuma and Imperial County to climb well into the triple digits, with highs potentially ranging from 103 to 109 degrees through the end of the week.

Because of the extreme temperatures, the National Weather Service has issued an Extreme Heat Warning for Southeast California beginning Wednesday and lasting through Sunday, with warnings expanding into Arizona deserts Thursday.

Meteorologists say this heat wave is unusually strong for March and could challenge or break several daily and monthly temperature records.

Even mornings may feel warm, with overnight lows only dropping into the mid-60s and low 70s. That could make it harder for people to cool down between hot afternoons.

Another concern is how quickly temperatures will rise during the day. Forecasters say temperatures could already reach the 90s before noon later this week.

Officials are urging people planning outdoor activities to stay hydrated, take frequent breaks in shaded or air-conditioned areas, and avoid strenuous activity during the hottest part of the day.

Relief may begin early next week as the high pressure system weakens slightly, but temperatures are still expected to remain well above normal across the region.