Hour-By-Hour Climb To A 108-Degree Heat Index In NoVA, DC

WASHINGTON, DC — As miserably hot and sticky as Sunday felt across northern Virginia, Monday will be even worse, say weather forecasters. A heat advisory will go into effect for much of the state from noon until 8 p.m., the National Weather Service said.

Heat index values — what the temperature feels like to people as heat and humidity combine — up to 108 degrees are possible. The heat index will likely be in the triple digits throughout Monday afternoon and early evening.

At 10 a.m., it was 89 degrees in Washington, D.C., and the heat index was already up to 97 degrees. See Monday's hour-by-hour forecast, which includes chances of thunderstorms throughout the work week, below.

A heat advisory is in effect until 8 p.m. Sunday for portions of the District of Columbia, central, northern and western Maryland, northern and northwest Virginia, as well as the eastern panhandle of West Virginia.

The heat advisory includes the District of Columbia, as well as portions of central and southern Maryland and central and northern Virginia.

The heat advisory area includes Prince William, Manassas, Manassas Park, Fairfax, Arlington, Falls Church, Stafford, Fauquier, Loudoun, Dale City, Woodbridge, Reston, Herndon, Annandale, Centreville, Chantilly, McLean, Franconia, Alexandria, Falmouth, Fredericksburg, Dahlgren, Warrenton, Turnbull, Purcellville, Leesburg, Ashburn, and Sterling.

The high heat and humidity pose the risk of illness. Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors, the National Weather Service said. Young children and pets should never be left unattended in vehicles under any circumstances.

Take extra precautions if you work or spend time outside. When possible reschedule strenuous activities to early morning or evening. Wear lightweight and loose fitting clothing.

Prolonged exposure to the high temperatures and humidity can cause heat-related illnesses like heat exhaustion or cramps — and heat stroke in severe cases. The Centers for Disease Control and Prevention has a list of symptoms to watch for and what to do in situations of heat stroke, heat exhaustion and heat cramps.

Health officials say you should stay inside during the heat wave, limit exposure to the sun, drink plenty of water and wear loose, lightweight and light-colored clothing. Residents should also check on neighbors with health issues or those without air conditioning.

Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency and you should call 911.

The Centers for Disease Control recommends that if you need to go to a cooling center, wear a cloth face covering. While you are there, wash your hands with soap, or use hand sanitizer, often.
Face covers should not be used by children under the age of 2. They also should not be used by people having trouble breathing, or who are unconscious, injured, or can't remove the mask themselves.

Here is the National Weather Service weather forecast for the week in DC and northern Virginia:

Monday: A chance of showers and thunderstorms after 2pm. Partly sunny and hot, with a high near 99. Heat index values as high as 108. West wind around 8 mph. Chance of precipitation is 30%.

Monday Night: A chance of showers and thunderstorms before 11pm, then a slight chance of showers after 2am. Mostly cloudy, with a low around 77. West wind 5 to 8 mph. Chance of precipitation is 30%.

Tuesday: A slight chance of showers, then a chance of showers and thunderstorms after 11am. Partly sunny and hot, with a high near 97. Heat index values as high as 104. North wind around 6 mph becoming light and variable in the afternoon. Chance of precipitation is 40%.

Tuesday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 77. South wind 5 to 7 mph becoming calm after midnight. Chance of precipitation is 50%.

Wednesday: A chance of showers and thunderstorms. Partly sunny and hot, with a high near 97. Calm wind becoming southwest around 5 mph in the afternoon. Chance of precipitation is 50%.

Wednesday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 77. Chance of precipitation is 50%.

Thursday: Showers likely, with thunderstorms also possible after 8am. Partly sunny, with a high near 94. Chance of precipitation is 60%.

Thursday Night: Mostly cloudy, with a low around 75.

Friday: A chance of showers and thunderstorms. Mostly sunny, with a high near 92. Chance of precipitation is 30%.

Friday Night: Partly cloudy, with a low around 72.

Saturday: Mostly sunny, with a high near 92.

Saturday Night: Partly cloudy, with a low around 73.

Sunday: Mostly sunny, with a high near 95.