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According to the National Weather Service, multiple heat records for the date have been set.
It was 91 degrees at UCLA, a number that surpasses the prior record of 87 degrees set 50 years ago in 1968. In downtown Los Angeles, the temperature reached 94 degrees. That temperature tied a record set in 1890.
Long Beach hit 95 degrees, breaking the 1968 mark of 91.
Burbank also set a heat record. Monday's 92 degrees topped the city's previous high of 91 set four years ago.