Yosemite, Yosemite Valley, Mariposa Madera Foothills and Mariposa-Madera Lower Sierra are under an updated weather alert for strong thunderstorms by the National Weather Service on Thursday at 8:29 p.m. “Minor hail damage to vegetation is possible.”Locations impacted by the alert include Yosemite National, Bootjack, Yosemite Valley, Mariposa, Tamarack Flat Campground, Metcalf Gap, El Portal, Badger Pass Ranger Station, Camp 4 Campground, Wawona Campground, Hodgdon Meadow Campground, Yosemite Glacier Point, Gin Flat, Wawona Vistor Center, Jerseydale, Bridalveil Creek Campground, Crane Flat Campground, Crane Flat and Wawona. Rainy roadways ahead: Essential safety tips for heavy rainWhen heavy rain pours, the risk of flooding and treacherous roads rises. In heavy rain, allow an additional two seconds of distance to compensate for reduced traction and braking effectiveness. In the face of heavy rain, these precautions can make a significant difference in ensuring your safety on the road.