District of Columbia-Frederick MD-Carroll-Northern Baltimore- Southern Baltimore-Prince Georges-Anne Arundel- Northwest Montgomery-Central and Southeast Montgomery- Northwest Howard-Central and Southeast Howard-Northwest Harford- Southeast Harford-Prince William/Manassas/Manassas Park-Fairfax- Arlington/Falls Church/Alexandria-Western Loudoun-Eastern Loudoun- Including the cities of Washington, Frederick, Ballenger Creek, Eldersburg, Westminster, Reisterstown, Cockeysville, Baltimore, Bowie, Suitland-Silver Hill, Clinton, College Park, Greenbelt, Laurel, Camp Springs, Glen Burnie, Annapolis, Severn, South Gate, Severna Park, Arnold, Odenton, Germantown, Damascus, Bethesda, Rockville, Gaithersburg, Silver Spring, Lisbon, Columbia, Ellicott City, Jarrettsville, Aberdeen, Dale City, Manassas, Woodbridge, Lake Ridge, Montclair, Reston, Herndon, Annandale, Centreville, Chantilly, McLean, Franconia, Arlington, Alexandria, Falls Church, Purcellville, Leesburg, Ashburn, and Sterling 352 AM EDT Fri Jul 19 2019 ...EXCESSIVE HEAT WARNING IN EFFECT FROM 11 AM THIS MORNING TO 9 PM EDT THIS EVENING... ...EXCESSIVE HEAT WATCH REMAINS IN EFFECT FROM SATURDAY MORNING THROUGH SATURDAY EVENING... ...EXCESSIVE HEAT WATCH REMAINS IN EFFECT FROM SUNDAY MORNING THROUGH SUNDAY EVENING... The National Weather Service in Baltimore MD/Washington has upgraded the Heat Advisory to an Excessive Heat Warning, which is in effect from 11 AM this morning to 9 PM EDT this evening. The Heat Advisory is no longer in effect. * HEAT INDEX VALUES...Near 110 degrees today, then potentially 110 to 115 degrees Saturday and Sunday due to temperatures in the upper 90s to around 100 degrees and dewpoints in the lower to middle 70s. * Impacts...Dangerously high temperatures and humidity could quickly cause heat stress or heat stroke if precautions are not taken. PRECAUTIONARY/PREPAREDNESS ACTIONS... An Excessive Heat Warning means that a prolonged period of dangerously high temperatures will occur. The combination of extreme temperatures and high humidity will create a dangerous situation in which heat illnesses are expected. Check in on relatives and neighbors. An Excessive Heat Watch means that a prolonged period of dangerously high temperatures is possible. Prepare for extreme temperatures and high humidity which would create a situation in which heat illnesses are expected. Take extra precautions if you work or spend time outside. 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. 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 - call 911. && By The National Weather Service, Sterling, Va.