August 14, 2023 - As we enter the warmer summer months, it’s an important reminder that the California Governor’s Office of Emergency Services (Cal OES) works around the clock with local, state and federal partners to mitigate any impacts from extreme weather. 

As part of that coordination, Cal OES has developed the Extreme Temperature Response Plan, which is a detailed playbook that outlines actions the state may take to support local and state partners during an extreme temperature event, hot or cold.

There are three phases of the Extreme Temperature Response Plan:

• Phase 1: Seasonal Readiness
• Phase 2: Heat or Cold/Freeze Alert
• Phase 3: Heat or Cold/Freeze Warning

Phase 1 Seasonal Readiness 

This phase begins annually in May as the warmer months approach for extreme heat and in November as colder months approach for extreme cold/freeze. 

During Phase 1, local and state agencies:

• Actively monitor the weather and assess available resources in the case of an extreme temperature event. 
• Run public safety campaigns to better educate Californians and at-risk populations on the steps necessary to stay safe from extreme temperatures. 

Phase 2 Heat or Cold/Freeze Alert 

This phase occurs when the National Weather Service (NWS) issues a heat or cold/freeze alert, or at the discretion of the Cal OES Director, when extreme temperature is predicted, or power disruptions occur during abnormal weather conditions.

During Phase 2, the state:

• Actively responds to this threat by coordinating with state and local government partners and assessing resource need. 
• Possibly activates the State Operations Center (SOC).
• Stand-by and activation (if needed) of state-owned facilities as cooling or warming centers.
• Coordinates with all local emergency managers to ensure the safety of California’s most at-risk communities, including older adults, individuals with disabilities, and anyone with access or functional needs

Phase 3 Heat or Cold/Freeze Warning 

This phase occurs when the NWS issues an extreme temperature warning not normal for the region that causes higher than normal medical emergencies, one or more local jurisdictions or a county proclaims an emergency due to a heat or cold/freeze warning, or at the discretion of the Cal OES Director. Cal OES assumes an enhanced response posture to respond to a significant threat to life and property by coordinating across state and local government to facilitate resource distribution.   

During Phase 3, the state:

• May issue a State of Emergency, through the Governor, at the recommendation of the Cal OES Director.
• Possibly activates the State Operations Center (SOC).
• Distributes state resources.
• Opens additional heating or cooling centers.
• Continues to ensure the safety of California’s most at-risk communities.

• Advises local governments to do wellness checks on at-risk communities.

Additional Resources:

Stay Safe During Extreme Heat
Cooling Centers

Children’s Water Safety

Swift Water Safety 
Source: CalOES