Helena is heading into one of the hottest weekends of the year, with high temperatures Saturday expected to reach between the mid-90s and low 100s — a range that puts the city in record-possible territory for late in the season. High pressure aloft has kept the heat locked in place through the week, and meteorologists say Saturday afternoon will be the peak before conditions begin to shift.
Overnight lows are not expected to offer much relief, which raises the risk for heat-related illness, particularly for older residents, young children, and anyone without air conditioning. Helena's older housing stock — much of it concentrated in neighborhoods near Last Chance Gulch and the surrounding hillsides — tends to hold heat through the night.
The pattern is forecast to break Saturday evening and into Sunday as an upper-level disturbance tracking across southern Canada knocks down the ridge. Cooler air and the chance for some moisture are expected to follow, though Saturday itself remains the critical window. Residents should plan outdoor activities for early morning, check on neighbors who may be vulnerable to heat, and keep hydrated through the day.