Wednesday is starting foggy for parts of north-central Montana, particularly east of Interstate 15, but forecasters say that fog will burn off quickly as the morning progresses, giving way to a sunny start before clouds build through the afternoon.
Scattered showers and thunderstorms are expected to develop in the afternoon and evening hours. The Helena valley could see some of that activity, though coverage is expected to be spotty rather than widespread. Temperatures will be warm heading into the afternoon before storm activity arrives.
Residents with outdoor plans Wednesday should be ready to adjust timing. Morning hours look clear and comfortable, with the best window for outdoor activity before noon. Those heading into the backcountry or onto the lake should watch conditions through the afternoon, as mountain thunderstorms can develop quickly and move faster than valley forecasts suggest.
The National Weather Service Helena office has current forecasts and any watches or warnings for Lewis and Clark County.