Heat index values up to 100. Overnight temperatures remaining warm in the lower 70s. * WHERE...Portions of central, east central, south central, southeast, southwest, and west central Minnesota and northwest and west central Wisconsin. * WHEN...Until 9 PM CDT Thursday. * IMPACTS...Hot temperatures and high humidity may cause heat illnesses. Prolonged heat waves lead to cumulative heat stress for those who cannot adequately cool down and recover each night. Cumulative heat stress significantly increases the risk of heat exhaustion and heat stroke as time goes on.

The Wisconsin Department of Natural Resources has issued an Air Quality Advisory for the following counties: Adams, Ashland, Barron, Bayfield, Brown, Buffalo, Burnett, Calumet, Chippewa, Clark, Columbia, Crawford, Dane, Dodge, Door, Douglas, Dunn, Eau Claire, Florence, Fond du Lac, Forest, Grant, Green, Green Lake, Iowa, Iron, Jackson, Jefferson, Juneau, Kenosha, Kewaunee, La Crosse, Lafayette, Langlade, Lincoln, Manitowoc, Marathon, Marinette, Marquette, Menominee, Milwaukee, Monroe, Oconto, Oneida, Outagamie, Ozaukee, Pepin, Pierce, Polk, Portage, Price, Racine, Richland, Rock, Rusk, Sauk, Sawyer, Shawano, Sheboygan, St. Croix, Taylor, Trempealeau, Vernon, Vilas, Walworth, Washburn, Washington, Waukesha, Waupaca, Waushara, Winnebago, Wood. WHAT...The PM2.5 AQI (24-hour average) is expected to reach the Unhealthy for Sensitive Groups (Orange) to Very Unhealthy (Purple) level. Hazardous (Maroon) NowCast AQI (1-hour average) will be possible. WHERE...Statewide. WHEN...From noon Tuesday until noon Thursday. Precautionary/Preparedness Actions: For Very Unhealthy (Purple) AQI: Sensitive groups: Avoid all physical activity outdoors. Reschedule to a time when air quality is better or move activities indoors. People with asthma: Follow your asthma action plan and keep quick-relief medicine handy. People with heart disease: Symptoms such as palpitations, shortness of breath, or unusual fatigue may indicate a serious problem. If you have any of these, contact your health care provider. Everyone else: Limit outdoor physical activity. Go indoors if you have symptoms. For Unhealthy (Red) AQI: Sensitive groups: Consider rescheduling or moving all activities inside. Go inside if you have symptoms. People with asthma: Follow your asthma action plan and keep quick-relief medicine handy. People with heart disease: Symptoms such as palpitations, shortness of breath, or unusual fatigue may indicate a serious problem. If you have any of these, contact your health care provider. Everyone else: Keep outdoor activities shorter and less intense. Go inside if you have symptoms. For Unhealthy for Sensitive Groups (Orange) AQI: Sensitive groups: Make outdoor activities shorter and less intense. It is OK to be active outdoors but take more breaks. Watch for symptoms such as coughing or shortness of breath. People with asthma: Follow your asthma action plan and keep quick relief medicine handy. People with heart disease: Symptoms such as palpitations, shortness of breath, or unusual fatigue may indicate a serious problem. If you have any of these, contact your health care provider. Additional Details: THIS ADVISORY WILL BE RE-EVALUATED THURSDAY MORNING AND WILL LIKELY BE EXTENDED FOR AT LEAST SOME PORTION OF THE STATE BEYOND NOON THURSDAY. Smoke from wildfires in Minnesota and Ontario will enter northern WI between 8 p.m. and midnight Tuesday night. The smoke will push south, approximately reaching an Eau Claire to Sheboygan line by noon Wednesday. Smoke will continue south-southwest, approximately reaching a La Crosse to Janesville line by midnight Wednesday night. Statewide impacts will be possible by 6 a.m. Thursday. The heaviest smoke impacts, including the potential for Hazardous (Maroon) NowCast AQI, are expected across northwest Wisconsin, especially in communities along Lake Superior. Lake enhanced smoke concentrations will also be possible for communities near Lake Michigan. For more information on current air quality, please see: https://airquality.wi.gov