Dangerous heat forecast from Plains to Ohio Valley, Heat Advisories issued across central U.S.
Major to Extreme HeatRisk conditions are forecast to develop across parts of the central United States this week as a strengthening heat dome expands over the region. National Weather Service offices have already issued Heat Advisories across portions of Kansas, Oklahoma, Arkansas, Missouri, Illinois, and Texas, where heat index values are forecast to reach 40 to 42°C (104 to 108°F).
Image credit: MSEMA
A major mid-June heat wave is forecast to affect a large portion of the central and eastern United States this week. The Weather Prediction Center (WPC) forecasts widespread Major (Level 3) HeatRisk and localized Extreme (Level 4) HeatRisk conditions from the southern Plains and Mid-Mississippi Valley into parts of the Midwest and Ohio Valley between June 9 and 12.
WPC forecasts this will be the most significant heat episode of the season so far for many locations, with dangerous heat persisting in some areas through June 15.
The highest HeatRisk levels are forecast across portions of Kansas, Oklahoma, Arkansas, Missouri, Illinois, and neighboring states, where temperatures and humidity are expected to combine to produce prolonged periods of dangerous heat stress.
Level 4 (Extreme) HeatRisk conditions indicate impacts are possible even for individuals without known heat sensitivity if adequate cooling and hydration are unavailable.
National Weather Service (NWS) offices across the central United States have begun issuing Heat Advisories ahead of the event. Forecast heat index values generally range from 40 to 42°C (104 to 108°F), while parts of the Texas Panhandle are forecast to reach air temperatures up to 42°C (107°F).
Advisories issued on June 8 span across portions of Texas, Oklahoma, Kansas, Arkansas, Missouri, and Illinois, covering several major population centers and surrounding counties.
The NWS office in Little Rock issued a Heat Advisory from 17:00 UTC to 01:00 UTC on June 10 (12:00 to 20:00 CDT June 9) for large portions of central, eastern, north-central, southeastern, and western Arkansas. Heat index values near or above 41°C (105°F) are forecast across areas including Little Rock, North Little Rock, Conway, Pine Bluff, Searcy, Russellville, Batesville, and numerous surrounding communities.
Further north, the NWS office in St. Louis issued a Heat Advisory from 17:00 UTC on June 9 to 03:00 UTC on June 10 (12:00 to 22:00 CDT June 9) for portions of southwest Illinois and central, east-central, and southeast Missouri. Forecast heat index values are expected to reach 42°C (108°F), affecting communities including St. Louis, St. Charles, Jefferson City, Belleville, Edwardsville, Farmington, and surrounding areas.
Heat Advisories have also been issued across eastern and northeastern Kansas by NWS offices in Topeka and Kansas City/Pleasant Hill. Heat index values up to 41°C (106°F) are forecast across the Kansas City metropolitan area and surrounding counties in eastern Kansas and western Missouri, including Leavenworth, Johnson, Wyandotte, Jackson, Clay, Platte, Cass, Lafayette, and Cooper counties.
Across northeast Oklahoma and northwest Arkansas, the NWS office in Tulsa issued a Heat Advisory from 18:00 UTC to 00:00 UTC on June 10 (13:00 to 19:00 CDT June 9). Heat index values up to 41°C (105°F) are forecast across portions of the Tulsa metropolitan area, Rogers County, Mayes County, Wagoner County, Ottawa County, Sebastian County, Crawford County, and Franklin County.
Additional Heat Advisories are in effect across portions of southern Kansas, northern Oklahoma, southwest Missouri, and the Texas Panhandle. The NWS office in Springfield, Missouri, warned that heat index values up to 40°C (104°F) may persist from noon CDT June 9 through 07:00 CDT June 10, extending the duration of heat exposure across parts of the Ozarks.
WPC forecasts the heat dome will gradually expand into the eastern United States later this week. Significant heat is expected to spread into portions of the Southeast, Mid-Atlantic, and Northeast, while elevated HeatRisk conditions may persist along parts of the East Coast through June 15.
Early-season heat waves frequently pose greater health risks than comparable events later in summer because many people have not yet acclimated to prolonged periods of excessive heat and humidity.
NWS warns that hot temperatures combined with high humidity may cause heat-related illnesses, particularly among older adults, young children, outdoor workers, individuals with chronic health conditions, and those without reliable access to air conditioning.
Residents across affected areas are advised to remain hydrated, limit strenuous outdoor activity during peak heating hours, seek air-conditioned environments whenever possible, and check on relatives and neighbors who may be vulnerable to heat stress.
References:
1 Heat advisories – NWS/WPC – June 8, 2026
I am an Assistant Editor and Severe Weather & Science Journalist at The Watchers, specializing in real-time severe weather coverage, geophysical event reporting, and research-driven scientific analysis. You can reach me at rishav(at)watchers(.)news.
Commenting rules and guidelines
We value the thoughts and opinions of our readers and welcome healthy discussions on our website. In order to maintain a respectful and positive community, we ask that all commenters follow these rules.