The NWS San Diego Heat Advisory for Orange County remains active, running from 10 AM Tuesday, Sept. 8 through 8 PM Thursday, Sept. 10, 2026. No upgrade to an Extreme Heat Warning has been issued as of the last update.

NWS projects coastal highs of 85–95°F and inland highs in the mid-to-upper 90s. Overnight lows are expected to hold in the mid 70s countywide, restricting the body's ability to recover from daytime heat stress. NWS HeatRisk is rated moderate to major — conditions that pose risk to heat-sensitive individuals at the moderate level, and to anyone without effective cooling or adequate hydration at the major level.

The advisory covers three NWS zones: Orange County Coastal Areas, Orange County Inland Areas, and the Santa Ana Mountains and Foothills.

This heat event overlaps the tail end of coastal flood and high surf advisories associated with Hurricane Marie's offshore swell, compounding conditions for anyone outdoors near the coast.

NWS San Diego has not yet indicated whether the advisory will be extended beyond 8 PM Thursday. Residents and visitors — particularly those without air conditioning, outdoor workers, elderly individuals, and young children — face elevated risk through the duration of the advisory. No cooling center activations or city/county emergency declarations have been reported in the evidence available at this time.