'Dangerously High Heat and Humidity,' Thunderstorms on Tap Monday For Long Island

A heat advisory has been issued for Long Island on Monday as the hottest airmass of the season moves into the region.

The advisory will be in effect from 11 a.m. until 6 p.m. The National Weather Service says temperatures will be in the low to mid-90s, but factor in the humidity and the heat index is expected to reach 101 degrees Monday afternoon.

The combination of the heat and humidity will increase the risk for heat-related health issues, especially for the elderly, those with chronic health problems such as lung and heart disease and those working outdoors, the NWS says.

A heat advisory is issued when the combination of heat and humidity is expected to make it feel like it is 100 to 104 degrees for two consecutive hours.

To reduce risk during outdoor work, 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. Dial 911 if you suspect someone has heat stroke.

Here are the symptoms of heat stroke, courtesy of the Mayo Clinic:

• High body temperature. A body temperature of 104 F (40 C) or higher is the main sign of heatstroke.
• Altered mental state or behavior. Confusion, agitation, slurred speech, irritability, delirium, seizures and coma can all result from heatstroke.
• Alteration in sweating. In heatstroke brought on by hot weather, your skin will feel hot and dry to the touch. However, in heatstroke brought on by strenuous exercise, your skin may feel moist.
• Nausea and vomiting. You may feel sick to your stomach or vomit.
• Flushed skin. Your skin may turn red as your body temperature increases.
• Rapid breathing. Your breathing may become rapid and shallow.
• Racing heart rate. Your pulse may significantly increase because heat stress places a tremendous burden on your heart to help cool your body.
• Headache. Your head may throb.

Scattered showers and thunderstorms will spread across Long Island Monday afternoon and evening. Some of the storms could produce gusty winds and heavy rain, the NWS says.

Here's the full forecast:

Sunday Afternoon- Mostly sunny, with a high near 91. West wind around 9 mph.

Sunday Night- Patchy fog after midnight. Otherwise, partly cloudy, with a low around 73. South wind 5 to 9 mph.

Monday- A 40 percent chance of showers and thunderstorms after noon. Some of the storms could produce gusty winds and heavy rain. Patchy fog before 9am. Otherwise, partly sunny, with a high near 93. Heat index values as high as 101. Southwest wind 6 to 11 mph.

Monday Night- A 40 percent chance of showers and thunderstorms, mainly before midnight. Some of the storms could produce gusty winds and heavy rain. Patchy fog after 9pm. Otherwise, mostly cloudy, with a low around 76. West wind around 7 mph becoming southwest in the evening.

Tuesday- Mostly sunny, with a high near 92. West wind 8 to 14 mph.