PHILADELPHIA (CBS)– The Pennsylvania Department of Environmental Protection has issued a Code Orange Air Quality alert for Thursday, May 18, for Philadelphia and the surrounding area.

The alert is in effect for:

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Pennsylvania: Delaware; Eastern Chester; Eastern Montgomery; Lower Bucks; Philadelphia; Upper Bucks; Western Chester; Western Montgomery

New Jersey: Atlantic; Atlantic Coastal Cape May; Camden; Cape May; Coastal Atlantic; Coastal Ocean; Cumberland; Eastern Monmouth; Gloucester; Hunterdon; Mercer; Middlesex; Morris; Northwestern Burlington; Ocean; Salem; Somerset; Southeastern Burlington; Sussex; Warren; Western Monmouth

Delaware: Delaware Beaches; Inland Sussex; Kent; New Castle.

Officials say the ridge of high pressure, which shifted over the eastern US on Wednesday, continues to slowly track off to our east.  This high pressure system will allow for clear skies (early in the day), light winds and temperatures to extend into the 90s for the second day in a row.

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The ozone is expected to rise into the Code ORANGE range.

Young children, the elderly and those with respiratory problems, such as asthma, emphysema and bronchitis, are especially vulnerable to the effects of air pollution and should limit outdoor activities.

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