The National Weather Service issued alerts across the country warning of potent storms, a heat wave and lingering toxic smoke.

LOS ANGELES - A prolonged heat wave will push wildfire danger higher across Southern California through at least Monday, with forecasters warning that hot temperatures, very low humidity and dry vegetation could allow fires to spread rapidly.

When a devastating heat wave, hurricane, flood or wildfire strikes, people often want to know: How much did human-caused climate change influence this event, if at all? For many years, scientists could answer that question only in general terms.

Although the deadly early July heat wave has shrunk significantly, dangerous heat still persists across portions of the South and West.

Add Yahoo as a preferred source to see more of our stories on Google. Massachusetts residents celebrating the Fourth of July on Saturday will have to find a way to beat the heat, as dangerously high temperatures are expected to continue through the holiday.