The heat (advisory) is on, again, for this afternoon

South Florida is sweltering under yet another heat advisory.

The National Weather Service’s alert is in effect from 11 a.m. through 7 p.m. today, but the warning is limited to three South Florida counties: Broward, Palm Beach and Miami-Dade. Advisories earlier this week included all seven counties on the southern tip of Florida.

The high temperatures this afternoon are forecast in the low to mid-90s, heat index values forecast to be in the 105-112 degree range until afternoon showers and thunderstorms set in later today.

Heat is one of the leading weather-related killers in the United States, resulting in hundreds of fatalities each year, according to the National Weather Service.

According to the office: Young children and infants are particularly vulnerable to heat-related illness and death, as their bodies are less able to adapt to heat than are adults. Also at risk: Older adults, particularly those with pre existing diseases, people with chronic medical conditions, and pregnant women. Extreme heat events have been linked to low birth weight, preterm birth, and infant mortality, as well as congenital cataracts.

Some tips to try to stay cool: Stay hydrated, and don’t wait until you’re thirsty to drink fluids and limit your sun exposure. Wear sunglasses and a wide-brimmed hat or cap.