Stay cool: Heat advisory in effect for all of South Florida until 6 p.m.

The National Weather Service has issued a heat advisory for all of South Florida today, including Palm Beach County.

The heat index, or “feels like” temperature, is expected to be in the low triple digits everywhere in the county today, ranging from 105 in Riviera Beach to 107 at Palm Beach International Airport, and 111 in Jupiter, the NWS said.

The advisory will last until 6 p.m.

Heat index temperatures from 103 to 107 degrees constitute an elevated excessive heat risk, meaning heat exhaustion is likely with prolonged exposure. Temperatures of 108 to 112 are considered a “significant” excessive heat risk, with dangerous and potentially deadly heat stroke likely with prolonged exposure, the NWS said.

A heat advisory means people sensitive to warm temperatures should take precautions to avoid heat illness, including staying hydrated and seeking breaks if working or playing outside. Signs of heat exhaustion or heat stroke include symptoms such as muscle cramps, excessive sweating, throbbing headache, passing out, confusion and seizures.

An excessive heat warning, the highest alert level on a four-tier scale, means everyone needs to take precautions to stay safe in the heat because "you may become seriously ill or even die," the NWS says.

Tips to beat the heat

Tips for keeping safe during excessively hot weather from the American Red Cross:

∎ If you suspect heat injury, call for help.

∎ Children and the elderly are among the most vulnerable.

∎ Try not to work outside in the hottest part of the day; if you must work in the heat, slow down.

∎ When outdoors, take frequent breaks in the shade.

∎ Drink plenty of water.

∎ If you wait until you feel thirsty, you're already getting dehydrated.

∎ Don't drink beverages containing caffeine or alcohol (sodas or beer). They interfere with the body’s temperature-regulating mechanisms.

∎ Sweating is the body’s mechanism for cooling. If you stop sweating, call for help.