Heat advisory, air quality health advisory in effect Monday in Riverhead and across most of L.I.

High heat and humidity will combine to produce heat indices of about 101 across the region and in the mid- to upper-90s locally, according to the National Weather Service in New York. 

A  heat advisory is in effect for much of Long Island, except in southeastern Brookhaven Town and on the South Fork, from noon today through 10 p.m. tomorrow.

With hot and humid conditions expected to continue, the heat advisory may be extended through Wednesday, the weather service said. 

An air quality health advisory is also in effect again today for the pollutant ground-level ozone. The air quality index is forecast to reach 101 in the Long Island region today and 105 in the New York City Metro region today.  An AQI of 101 to 150 is considered unhealthy for sensitive groups, including children, the elderly and people with cardiovascular disease and respiratory disease such as asthma. 

A heat advisory is issued when the combination of heat and humidity is expected to make it feel like it is 95 to 99 degrees for two or more consecutive days, or 100 to 104 degrees for any length of time, the National Weather Service said in the advisory.

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Seniors and those with chronic health problems or mental health conditions are at an increased risk, according to the advisory.

Homes without air conditioning can be much hotter than outdoor temperatures, the weather service said, and people who live in homes without air conditioning should seek out cool spaces each day as long as it remains hot, and for a few days after if your home is still hot. 

To reduce risk during outdoor work, the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency! In cases of heat stroke call 9 1 1.

According to the Centers for Disease Control and Prevention,  approximately 1,220 people in the United States are killed by extreme heat every year, even though heat-related deaths and illnesses are preventable. More information from the CDC.

High heat can be dangerous for pets, who can suffer from heat illnesses including heat stroke. The Humane Society provides information on keeping dogs and cats safe during hot weather.

Never leave a pet inside a vehicle for any length of time during hot weather, even with the windows open. Temperatures inside a parked vehicle can quickly rise to unsafe, even deadly, levels .

Suffolk County law prohibits tethering, tying up or confining a dog outside when the temperature is above 90° F. It is a misdemeanor punishable by a fine of $250 for the first offense.