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San Mateo County Health System offers guidance on heat-related illnesses during Labor Day Weekend


The National Weather Service has issued an Excessive Heat Warning for hot weather beginning today through the Labor Day weekend. An Excessive Heat Warning is issued when there is a prolonged period of hot temperatures where people can become seriously ill if precautions are not taken. Temperatures could reach up to 110 degrees. There is a high risk of heat related illness, especially for sensitive groups: elderly people, children, sick people, as well as pets and livestock. This heat will also be dangerous to anyone without proper hydration or adequate cooling.

The San Mateo County Health System reminds people to take the necessary precautions to avoid heat-related illnesses. Residents are encouraged to drink plenty of cool, nonalcoholic beverages regardless of activity level to help prevent heat related illness and injuries.

Heat cramps, which occur as muscle pains and spasms, are often the first signal that the body is having trouble with the heat. Painful heat cramps often occur in the legs and can be accompanied by flushed, moist skin. Treatment involves moving to a cool place to rest, removing excess clothing, placing cool cloths on skin, and fanning skin.

Heat stroke is a serious illness characterized by a body temperature greater than 105 degrees. Symptoms may include dry red skin, convulsions, disorientation, delirium, and coma. Onset of heat stroke can be rapid; serious symptoms can occur within minutes. Treatment involves the rapid lowering of body temperature by taking a cool bath or applying wet towels to the body. Keep victims of heat stroke in a cool area and call 911 immediately.

Heat exhaustion is a milder form of heat stroke. Signs of heat exhaustion include extreme weakness, muscle cramps, nausea, or headache. Victims may also vomit or faint. Heat exhaustion is treated with plenty of liquids and rest in a cool, shaded area.
To avoid heat-related illness:

  • Stay indoors as much as possible and limit exposure to the sun.
  • Drink plenty of fluids and replace salts and minerals in your body. Anyone on a fluid-restricted diet or who has a problem with fluid retention should consult a doctor before increasing liquid intake. People with epilepsy or heart, kidney, or liver disease should also consult a doctor before increasing liquid intake. A sports beverage can replace the salt and minerals you lose in sweat. Avoid using salt tablets unless directed to do so by a physician.
  • Avoid alcoholic beverages.
  • Closely monitor local media for the latest information.
  • Seek out air-conditioned places, such as public libraries, shopping malls, or other indoor public spaces.
  • Stay on the lowest floor, out of the sunshine if air conditioning is not available.
  • Check on family, friends, and neighbors who do not have air conditioning and who spend much of their time alone, especially the elderly.
  • NEVER leave children or pets alone in closed vehicles.
  • Make sure your pets are protected, in cool spaces, and have access to water at all times.
  • Avoid strenuous work during the warmest part of the day. Use a buddy system when working in extreme heat, and take frequent breaks.
  • Eat well-balanced, light, and regular meals. Hot, heavy meals add heat to your body. Avoid using salt tablets unless directed to do so by a physician.

San Mateo County libraries are available as cooling centers. Locations and operating hours may be found by visiting:

In addition, the following facilities are open in San Mateo County on Saturday, September 2nd:

Community Room, City Hall
2415 University Ave.
East Palo Alto
Available: Air conditioning and water

Senior Center
2645 Alameda de las Pulgas
San Mateo

King Community Center
725 Monte Diablo
San Mateo

For more information on how to stay safe during the heat wave and to avoid heat-related illness, visit