Millions in the South West face heat warnings over the weekend

Dangerous and potentially deadly heat will settle over the southwestern United States for much of the weekend, with temperatures expected to break records and exceed 100 degrees in some locations.

Nearly 38 million people from California to south Texas are on some form of heat alert during at least part of the weekend, the National Weather Service said. A heat wave is defined as a period of unusually and uncomfortably hot and unusually humid weather lasting two days or more.

“Please protect yourself,” according to the weather service office in Phoenix warned residentswhile the Sacramento office said the heat would affect everyone, not just those most sensitive to heat risks. Meteorologists in San Diego advise local residents to learn the signs of heat exhaustion and heat stroke.

Here’s what you should know.

What’s the prognosis?

It will be dry and very hot. An excessive heat warning was in effect for the San Diego area through Sunday night, where temperatures of up to 115 degrees were forecast. Similar heat conditions were expected around the Grand Canyon and other parts of central and southwestern Arizona. Las Vegas, a city used to rising temperatures, could hit 109 degrees. Some of the most extreme heat is forecast in Death Valley along the California-Nevada border, where mercury could rise to 120 degrees.

As of Saturday, a heat warning was in effect for much of south-central California and western Nevada. Temperatures up to 102 degrees were expected in the Los Angeles area and up to 106 degrees in the San Joaquin Valley. The Reno, Nevada Weather Service said temperatures were expected to peak at around 100 degrees on Friday and that the possible record-breaking highs were unusually early in the summer season. On average, Reno doesn’t usually hit the 100-degree mark until July 10, meteorologists said. Parts of Utah and New Mexico were also under the recommendation, as was part of south Texas, where temperatures of between 100 and 105 degrees were forecast on Friday.

How bad will it get?

Don’t expect the heat to abate any time soon. This is the beginning of a potentially hot summer.

In a report released last month, the National Oceanic and Atmospheric Administration said that above-average temperatures were likely in June, July and August in almost all of the lower 48 states, with the exception of small areas in the Pacific Northwest and northern plains. In addition to high temperatures, the agency expected below-average rainfall in the west, which continues to face a gripping drought.

What precautions should I take?

This is the first heat event of the summer season, meteorologists said, adding that many people are not yet used to the heat and may be more affected by high temperatures than normal.

Forecasters said now is a good time to ensure cooling systems are in good working order. They also said to stay in air-conditioned rooms and reminded residents that children and pets should never be left alone in vehicles.

As always, staying hydrated during heat events is important. Drink more water than normal and avoid dehydrating alcoholic, sugary, or caffeinated beverages.

What is the heat index?

According to Kimberly McMahon, meteorologist at the National Weather Service, the heat index is a measure of how hot it really feels outside when humidity and other factors are factored in along with temperature.

While the heat index is routinely used to provide a more accurate measure of how it feels outside, meteorologists also use it to indicate exactly how much heat the human body can handle. According to the weather service, dizziness, thirst and profuse sweating are signs of heat exhaustion. The signs of heat stroke are more serious and may include confusion and loss of consciousness. In this case, call 911 and move the person to a cooler area.

when will it end

Depending on location, most heat warnings expire on Saturday evening or Sunday evening.

The recent heat waves have been deadly.

Late last month, sweltering heat and humidity were setting or breaking heat records in cities from Texas to Massachusetts. And last summer, record-breaking heat over the Pacific Northwest killed hundreds and threatened the health of workers in the fields and camps.

According to a team of researchers, the deadly weather event would have been all but impossible without climate change.