The National Weather Service had 47 active heat advisories in effect Sunday across 14 states and Puerto Rico, as the heat dome responsible for triple-digit readings in the West over the past two days expanded its footprint into the Midwest and Ohio Valley.
The alert count is down from the 52 advisories posted a day earlier, but the geographic spread has widened. New advisories are now up in Illinois, Kansas, Kentucky, Missouri, Oklahoma and Puerto Rico — areas not on Friday’s list — while New Jersey has dropped off. States still under advisories include California, Colorado, Florida, Nevada, New Mexico, New York, Texas and Utah.
In Illinois, the National Weather Service has advisories covering Christian, Shelby, Cumberland, Clark, Effingham, Jasper, Crawford, Clay, Richland and Lawrence counties, putting a swath of the state’s east-central and southeastern counties under heat risk alongside the traditional Western hotspots.
Colorado remains one of the most heavily affected states, with advisories stacked across the Front Range and southeastern plains. The National Weather Service says the Denver metro area, its western suburbs and the Boulder corridor face highs of 95 to 102 degrees through 8 p.m. MDT this evening. Farther southeast, Crowley, Otero, Prowers and Bent counties — including La Junta, Las Animas and Lamar — are forecast to reach 102 to 108 degrees. Pueblo County highs are expected to hit 97 to 105 degrees, with El Paso and eastern Fremont counties running 92 to 102 degrees.
California continues to carry the bulk of the West’s advisories, with dozens of zones stretching from the Sacramento and San Joaquin valleys through the Sierra foothills and Shasta County, mirroring the coverage seen Friday. Nevada’s advisories remain concentrated in the Sheep Range and the Spring Mountains-Red Rock Canyon area outside Las Vegas.
The pattern suggests the ridge of high pressure driving the heat is beginning to flex eastward rather than easing, pulling more of the central U.S. into hazardous-heat territory even as some Western zones see slightly lower alert totals than a day ago. The National Weather Service continues to warn that hot temperatures across the advisory areas can cause heat illness, particularly for outdoor workers and those without reliable air conditioning, and advises hydration and limiting midday exposure through the duration of each local advisory window.
Residents in the affected corridor can check local conditions via Denver weather and Sacramento weather for the latest advisory timing in those metro areas.