Long Island Weather: Heat Index To Hit 106 Degrees Sunday

Saturday was somehow the "cooler" day of this weekend. Temperatures are expected to approach triple digits Sunday and the heat index, how hot it feels when humidity is factored in, may reach 106 degrees on parts of Long Island.

An excessive heat warning is in effect until 9 a.m. Monday for northern Nassau County. A heat advisory is in effect until 9 p.m. Sunday for the rest of the island. It was already 83 degrees at Republic Airport in Farmingdale at 7:53 a.m.

Take extra precautions if you work or spend time outside Sunday, the National Weather Service says. When possible, reschedule strenuous activities to early morning or evening.

Know the signs and symptoms of heat exhaustion and heat stroke. Wear light weight and loose fitting clothing when possible, and drink plenty of water.

RELATED: 10 Hot Weather Safety Tips During LI Heat Wave

Sunday will likely be the hottest day of the week, but the heat wave won't be ending anytime soon. High temperatures will be near 90 degrees the entire work week.

"Last summer, the longest stretch of 90-degree days was mostly in the four- to five-day range for areas north of the Mason-Dixon Line," AccuWeather Long-Range Meteorologist Paul Pastelok said.

This heat wave could range from six to eight days in many areas.

But at least it's not this:

The full forecast:

Sunday- Sunny, with a high near 97. Heat index values as high as 105. West wind around 5 mph becoming calm.

Sunday Night- Mostly clear, with a low around 75. South wind around 6 mph becoming light and variable after midnight.

Monday- Sunny, with a high near 91. Heat index values as high as 95. Northeast wind 5 to 8 mph becoming south in the afternoon.

Monday Night- Mostly clear, with a low around 73. South wind 3 to 8 mph.

Tuesday- Sunny, with a high near 89. South wind 3 to 8 mph.

Tuesday Night- Mostly clear, with a low around 73.

Independence Day- Mostly sunny, with a high near 89.

Wednesday Night- A 30 percent chance of showers and thunderstorms before 10pm. Partly cloudy, with a low around 74.

Thursday- Mostly sunny, with a high near 89.

Thursday Night- Partly cloudy, with a low around 73.