A historic heat wave is shattering temperature records across the US West Coast as a powerful heat dome pushes inland temperatures above one hundred degrees Fahrenheit.Major cities including San Francisco and Los Angeles recorded their hottest March days in decades while Phoenix and Las Vegas brace for unprecedented early triple-digit heat.National Weather Service officials warned that inland desert regions and parts of Grand Canyon Park could surpass one hundred and four degrees during the peak of the event.Authorities are warning of increased wildfire risks and potential water shortages in Colorado due to accelerated snowpack melt and dry conditions.