UPDATE: Heat advisory for North Texas until Tuesday evening, says the NWS

On Monday at 4:55 a.m. an updated heat advisory was issued by the National Weather Service valid from noon until Tuesday 7 p.m. The advisory is for Cooke, Grayson, Fannin, Lamar, Denton, Collin, Hunt, Delta, Hopkins, Tarrant, Dallas, Rockwall, Kaufman, Van Zandt, Rains, Johnson, Ellis, Henderson, Hill, Navarro, Freestone, Anderson, Bell, McLennan, Falls, Limestone, Leon, Milam and Robertson counties.

Heat index values up to 109 degrees expected for portions of north central, northeast, and south central Texas from noon today to 7 p.m. Tuesday.

"Hot temperatures and high humidity will increase the risk for heat-related illnesses to occur, particularly for those working or participating in outdoor activities," states the NWS.

This advisory is in effect until Tuesday at 7 p.m.

Tips from the NWS for staying safe during a heat wave

• Stay hydrated: Remember to drink plenty of fluids.

• Find cool shelter: Stay in an air-conditioned room.

• Look out for others: Stay out of the sun, and check up on relatives and neighbors.

• Child and pet welfare: Never forget to safeguard young children and pets by not leaving them unattended in vehicles, especially during scorching weather when car interiors can become life-threateningly hot.

• Exercise caution outdoors: If you work or spend time outside, take additional safety measures.

• Select the ideal time: If possible, move strenuous activities to early morning or evening for more favorable conditions.

• Recognize warning signs: Familiarize yourself with symptoms of heat exhaustion and heat stroke.

• Dress for comfort: Wear lightweight and loose-fitting clothing to stay cool.

For a safer outdoor work environment, follow the Occupational Safety and Health Administration (OSHA)'s guidance by scheduling regular rest breaks in shaded or air-conditioned places. If anyone shows signs of heat illness, promptly move them to a cool, shaded area. In an emergency, call 911.

Source: The National Weather Service