The National Weather Service office in Great Falls issued a heat advisory beginning noon Saturday and running through 3 a.m. Sunday, warning residents across portions of central, north central, and southwest Montana — including the Helena area — to expect high temperatures up to 102 degrees. The advisory was posted just after midnight Friday.
That kind of sustained heat is more than uncomfortable — it's a genuine public health risk, particularly for older residents, young children, and anyone working or exercising outdoors during the afternoon hours. The NWS specifically flagged the danger of leaving children and pets in unattended vehicles, noting that car interiors can reach lethal temperatures within minutes even when outside air feels manageable. Drinking fluids throughout the day, before thirst sets in, is one of the most effective ways to avoid heat exhaustion.
Helena sits in a valley that can trap heat, and weekend afternoons on Last Chance Gulch and in neighborhoods without mature tree cover will feel the full weight of Saturday's forecast. Residents without air conditioning should identify a cool location — the main branch of the Helena Public Library on North Last Chance Gulch, the Capital City Mall, or other air-conditioned public buildings — and plan to spend the hottest part of the day there. The advisory expires in the early morning hours Sunday, with temperatures expected to fall overnight.