Ozone alerts, a welcome scarcity
For only the fifth time this summer, the region is under an “ozone action” alert.
The announcement that a "code orange" alert for ozone has been issued for Philadelphia and neighboring counties reinforced to us just how benign this summer has been.
This marks only the third time this season that such an advisory has been issued. By comparison, 27 such advisories were issued in 2010, according to the state Department of Environmental Protection.
Ozone is a product of sun and heat, and, very simply, we just haven't had much of the latter.
Philadelphia has had no prolonged heat waves, and through yesterday the average temperature since June 1 was a mere one-third of a degree above normal.
Given how generally mild it has been, tomorrow's flirtation with 90 might seem more uncomfortable than it would have in most other summers.
Looking well ahead, no serious heat appears on the horizon. It is getting late – and the nights are becoming longer, about 45 minutes longer than they were at the solstice.
But for one day at least, it will feel like summer tomorrow, although the heat indices shouldn't feel all that bad.
On "ozone" action days, the DEP and the Air Quality Partnership of the Delaware Valley advise people, especially the elderly and those with respiratory problems to limit outdoor activities.
Thankfully, those advisories have been scarce this summer.
According to the DEP, in 2013, the region experienced 9 ozone-action days; 18, in 2012; 22, in 2011; 27, in 2010, and 7, 2013.
Pittsburgh by the way, has had none this summer.