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Posted at 04:40 PM ET, 07/21/2011

PM Update: Excessive heat warning extended into Saturday; code red air quality Friday

Sweat Ceiling 2011

Excessive heat warning tonight, Friday and Saturday
Code red air quality Friday: unhealthy for general population
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We’re now literally in the thick of this oppressive heat wave, with the worst still to come. Heat indices today climbed to 110-115 (air temps to the upper 90s) and may reach higher levels Friday. In addition, air quality levels are expected to be unhealthy Friday, and a code red alert has been issued. Because humidity levels are so high - night time cooling will be minimized. As such, the hours of the excessive heat warning have been extended to 10 p.m. tonight, and from 10 a.m. to 10 p.m. Friday. And with triple digit heat and stifling humidity likely again Saturday, the warning is now in effect then too, from 10 a.m. to 8 p.m.

Through Tonight: Simply stifling. Temperatures hover in the 90s through the evening hours before only slowly trickling back through the 80s after midnight in most spots. Lows range from just the low 80s in the city, to the upper 70s in the cooler suburbs. The record high minimum temperature of 81 may well be surpassed at Reagan National. Heat indices likely remain above 100 through midnight in urban areas. Evening joggers/bikers should take it easy, and take extra care in hydrating.

Tomorrow (Friday): Combining the heat and humidity, it’s perhaps the most extreme day in 15 years. High temperature surge to 99-104, with dangerous heat indices of 114-118. Add bad air quality into the equation, and consider cutting back on any planned time outside. An isolated thunderstorm can’t be ruled out but is more likely towards the Mason Dixon line.

See David Streit’s forecast through early next week. And if you haven’t already, join us on Facebook and follow us on Twitter

Code red air quality recommendations: Clean Air Partners recommends active children and adults, and people with lung disease, such as asthma, should avoid prolonged or heavy exertion outdoors. Everyone else, especially children, should reduce prolonged or heavy exertion outdoors.

On Code Red days, everyone is advised to follow the action steps below to protect their health:

* Sign up for air quality alerts at cleanairpartners.net.
* Turn off lights and electronics when not in use.
* Avoid lawn mowing or use an electric mower.
* Telework and take public transit.
* Do not use chemicals on your lawn and garden.

Hurricane Dora: While starting to slowly weaken in the eastern Pacific and forecast to just brush the southern tip of Baja California, Dora maintains an impressive satellite appearance. The category 4 storm has peak winds of 150 mph.

By  |  04:40 PM ET, 07/21/2011

Categories:  Forecasts

 
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