Heat Indexes Climb Above 120 in Region

The heat flirted with new records Friday, even setting one at Dulles International Airport.

The high at Dulles reached 105 degrees -- an all-time high. At Baltimore-Washington International Thurgood Marshall Airport, the high reached 106 degrees -- one below the all-time high.

Closer to D.C., there was a high temperature of 102 at Reagan National Airport, one below the record high for July 22, with a heat index high of 121, which was one below the all-time record there, News4 Chief Meteorologist Doug Kammerer reported.

At 2 p.m., the temperature in the District had climbed to 102 degrees with a heat index over 116. Last summer, if you recall, was the hottest on record in D.C., yet the heat index never got above 110. 

At 3 p.m., the temperature reached 106 in Warrenton, Va., according to News4 meteorologist Tom Kierein.  And, get this, the heat index was 133.  After talking with officials, however, it's not clear if that weather station is calibrated correctly, but the heat index should still be in the 120s.

Through 1 p.m. Friday, many areas recorded heat indexes over 115, and more than a few areas were over 120, according to Kammerer.

Friday afternoon and early Friday evening storms moved through the area and helped cool things off a bit, with the temperature dropping back to around 90 degrees, though the storms missed D.C. by a couple of miles.

With the slight cool down, the excessive heat warning was canceled early -- before 8 p.m. -- instead of expiring at 10 p.m., but a warning also issued for Saturday from 10 a.m. to 8 p.m. will still be in effect.

Kammerer said that on Saturday the heat index could be a little lower, but it will be almost as hazy, hot and humid -- very humid in the morning, Kammerer said. Expect high temperatures from 97-102 and the heat index from 110-120. And there is a better chance of storms Saturday afternoon.

A cold front will move in to offer relief from the heat wave Sunday, but we could be entering another intense heat wave next week.

Along with the heat and humidity, the region also has to deal with poor air quality. A Code Red air quality alert was in effect Friday. Everyone should limit strenuous outdoor activity because the air is unhealthy to breathe. Turn off as many lights and appliances as possible, don't drive if you don't have to, do not apply chemicals to your lawn or garden, and avoid mowing.

Stay indoors if you can, but if you have to go out, keep your physical activity to a minimum. Stay hydrated and look out for the elderly and pets.

Metro riders should remember that the transit agency is often dealing with air conditioning problems, so if you wind up on a hot car, get off at the next stop, walk down two cars and get back on. Metro railcars operate as pairs so every two cars share the same problem.

Power companies are preparing to deal with outages. Pepco and Baltimore Gas & Electric say the region's power supply is expected to be enough to meet demand, but the utilities are advising customers to take steps to save energy. Pepco and BGE are staffing to quickly address any equipment issues that may arise from heat or potential storms resulting from the heat.

  • Set air-conditioning thermostats at 78 degrees and use an electric fan, which doesn’t require as much energy, and the air will seem cooler without sacrificing comfort.
  • Keep window shades, blinds, or drapes closed to block the sunlight during the hottest part of the day and retain cooler air inside your home or business.
  • Limit the use of electrically heated water and turn off non-essential appliances and as many lights as possible.
  • Limit opening refrigerator or freezer doors.
  • Postpone using high-energy appliances like electric stoves, washing machines, dishwashers and dryers until the evening.

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