With a heatwave of 100-degree weather on the horizon, “much of the population” across Colorado’s Eastern Plains and the Denver area will face severe heat risks over the weekend, according to the National Weather Service. Temperature highs of 101 degrees Friday will put the Denver area and Interstate 25 corridor under a “major risk” heat advisory, and the Eastern Plains will face “moderate” heat risks, according to NWS forecasters. A “major risk” heat advisory means that much of the population is at risk of illness from heat exposure, and a “moderate” advisory means those who are sensitive to heat or don’t have access to effective cooling and hydration are at risk, forecasters said. RELATED: How to stay cool during extreme heat: Tips for preventing heat-related illness The only step above a “major risk” advisory is an “extreme risk” advisory, where there’s little to no overnight relief during periods of long heat duration. Temperatures are also expected to reach 101 degrees on Saturday, but the “major risk” heat advisory will expand eastward, including most of the plains in east-central Colorado, forecasters said. In Denver and areas near Fort Collins, the heat risk Saturday morning will become “extreme,” according to NWS forecasters.