New Delhi, July 10 -- A vast and unusually intense heat dome is set to blanket most of the contiguous United States, driving temperatures to dangerous levels in what the National Weather Service (NWS) has described as "significant and dangerous" heat.

Forecasters said the heat wave will begin over the weekend and persist for at least a week, with some regions expected to endure above-normal temperatures through the end of the month. Daytime and overnight temperatures are forecast to run 15 to 25 degrees Fahrenheit (8 to 14 degrees Celsius) above seasonal averages in many areas. Elevated nighttime temperatures are expected to heighten health risks and make it more difficult to contain the country's already active wildfire season.

Daniel ...