In light of the extended hot weather forecasted for San Joaquin County, here are tips that provide detailed information about what to do during extended hot weather to prevent heat stress. San Joaquin County is experiencing a wave of prolonged high heat and humidity that can be dangerous and even life-threatening. “Take precautions that will protect yourself and your family, but I also encourage you to reach out and extend your help to others,” said Dr. Cora Hoover, San Joaquin County Assistant Public Health Officer.