Wild weather weekend: US will have both a 'dangerous' heatwave and 'significant' snowstorm

Wild extremes of weather are the story across the U.S. heading into the weekend, as a May heat wave sends temperatures soaring in the East and a late-season snowstorm buries portions of the West.

The early season heat wave will affect parts of the East on Friday and especially Saturday, with afternoon high temperatures expected to hit the 90s in many areas. "High temperatures are forecast to be between 20-30 degrees above average for much of the mid-Atlantic and Northeast on Saturday," the National Weather Service said.

"Daily and monthly record highs could be challenged if not broken," the Weather Service in Boston said.

Twenty-five million people are under a heat advisory in the Northeast, the Weather Service said, which called the heat wave "dangerous," since it was so early in the season and given number of outdoor events expected this weekend, including numerous college commencements.

The combination of hot temperatures and high humidity may cause heat illnesses to occur.

"Seniors and those with chronic health problems or mental health conditions are at an increased risk," the Weather Service in New York said. "Homes without air conditioning can be much hotter than outdoor temperatures."

In many areas, the heat and humidity this Saturday and Sunday will bring the hottest conditions since last August, and in some locations, record highs that have stood for more than 100 years could be broken, AccuWeather said.

Snowstorm to hit West

While the East swelters, portions of the West will see a late-season blast of cold and snow. Winter storm watches and warnings were in effect Friday across a large section of Colorado and northward into Wyoming.

Up to half a foot of snow was possible late Friday and early Saturday in downtown Denver. "Some places on the southern and western side of the Denver metro area could see as much as a foot of snow pile up, enough to potentially result in widespread power outages," said AccuWeather meteorologist Alex Sosnowski.

Paul Schlatter, a meteorologist at the National Weather Service in Boulder, Colorado, said "we can say with a high degree of confidence the foothills are going to see pretty significant snow. And we are confident that it will be cold enough Friday night that we will see some snow accumulation along the I-25 corridor."

AccuWeather meteorologist William Clark said "With trees leafing out in the lower and intermediate elevations, even a couple of inches of wet, clinging snow can cause problems ranging from limbs breaking to power outages and blocked roads."

Some people could wake up without power in their homes Saturday morning, AccuWeather said. Motorists that plan on being on the roads late Friday night to early Saturday may face hazards ranging from slippery conditions to fallen trees.

Contributing: The (Fort Collins) Coloradan

This article originally appeared on USA TODAY: Weekend weather: US will see both heatwave and snowstorm