Heat advisory: San Bernardino County mountain communities below 6,000 feet face 90s through Friday

The National Weather Service office in San Diego issued a Heat Advisory at 9:59 PM PDT Sunday, August 25, warning that high temperatures in the 90s are expected across San Bernardino County mountain communities below 6,000 feet through 8 PM Friday, August 28[1].

Conditions are expected to worsen as the week progresses. NWS warns that temperatures will continue rising through Friday, increasing the threat of heat illness across the region[1]. Making matters worse, overnight lows will run 10 to 15 degrees above normal, meaning residents in affected areas will have limited opportunity to cool down between hot days[1].

Note for Big Bear Valley readers: Big Bear Lake sits at approximately 6,752 feet in elevation — above the 6,000-foot advisory threshold. However, lower-elevation communities in the surrounding mountains do fall within the advisory zone. Residents should check their specific elevation if uncertain whether they are affected.

Heat-related illnesses — including heat exhaustion and heat stroke — increase significantly during extended heat events like this one[1]. Residents at lower elevations should take extra precautions: stay hydrated, limit strenuous outdoor activity during peak afternoon hours, and check on elderly neighbors and those without air conditioning. Local guidance from San Bernardino County public health or emergency services was not available at time of publication.