An abnormal autumn heat wave continued to bake the western United States over the weekend, setting temperature records in cities like San Francisco and Denver that hadnt been touched in decades.On Saturday, Denvers daily high reached a record 87 degrees breaking the previous record of 86 set back in 1997, according to the National Weather Service.This past September was the hottest in Denvers recorded weather history. The summer had already been the second hottest on record for the Colorado capital, averaging 75 degrees when a normal summer would average 72 degrees, the National Weather Service said.RELATED STORY | Heat-related deaths increased 117% in 24 years, CDC data showsCities around Californias Bay Area, which is known for its milder temperatures, broke daily heat records on Sunday.Downtown San Francisco recorded a high of 97, previously a record of 94 degrees set in 1992 for the daily high. Redwood City saw a high of 102 when the previous high set in 19987 was 99 degrees. And San Rafael was a scorching 107 on Sunday, having set a previous record of 95 in 2023.The National Weather Service said Sunday marked the third day this month of San Francisco reaching at least 94 degrees.RELATED STORY | Sunday, July 21 was the hottest day ever measured on EarthThe heat wave also set records in cities across Arizona, New Mexico and Montana, experts said.Meteorologists said cooler, fall weather is coming to the western U.S., it will just be later in the season.