8/4/2025 3:01:00 PM until 8/5/2025 11:45:00 PM

This warning is reserved for only the hottest days of the year and is issued when temperatures are expected to rise to dangerous levels. Day hikers on Bright Angel Trail should descend no farther than 1 1/2 miles from the upper trailhead. Between the hours of 10 AM and 4 PM, hikers should be out of the canyon or at Havasupai Gardens or Bright Angel campgrounds, physical activity is discouraged. All hikers should have adequate gear, including a wide-brimmed hat, sunscreen, salty snacks, sufficient water, and electrolyte mix. Doubling your calorie intake helps maintain your energy. Hike smart. Take action when you see symptoms of heat exhaustion and heat stroke. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency! Call 9 1 1. Stay cool, stay hydrated, stay informed.

The Air Quality Advisory issued by the Michigan Department of Environment...Great Lakes...and Energy remains in effect and has been extended through Tuesday evening, August 5. This advisory is in effect for elevated levels of fine particulates (PM2.5). Pollutants are expected to be in the Unhealthy for Sensitive Groups range. The alert is in effect for the following Michigan Counties, Chippewa, Mackinac, Emmet, Cheboygan, Presque Isle, Leelanau, Antrim, Otsego, Montmorency, Alpena, Benzie, Grand Traverse, Kalkaska, Crawford, Oscoda, Alcona, Manistee, Wexford, Missaukee, Roscommon, Ogemaw, Iosco, Gladwin, and Arenac. The main culprit remains Canadian wildfire smoke originating from Manitoba and Ontario. Weak high pressure is holding the smoke in place and compressing it close to the ground. Current forecast indications are that smoke concentrations and air quality should improve Wednesday. It is recommended that, when possible, you avoid strenuous outdoor activities, especially those with heart disease and respiratory diseases such as asthma. Monitor for symptoms such as wheezing, coughing, chest tightness, dizziness, or burning in nose, throat, and eyes. Reduce or eliminate activities that contribute to air pollution, such as outdoor burning, and use of residential wood burning devices. Keep windows closed overnight to prevent smoke from getting indoors and, if possible, run central air conditioning with MERV-13 or higher rated filters. For further information, please see EPA's Air Now site for up-to- date air quality data at https://www.airnow.gov For further health information, please see MDHHS' Wildfire Smoke and Your Health site at https://www.michigan.gov/mdhhs/safety-injury- prev/environmental-health/your-health-and-wildfire-smoke.