Dog Day hiatus

While not a scientific phrase, “Dog Days” generally refer to the period from early July to mid-August that coincides with the warmest times of the year in the Northern Hemisphere.

That also happens to be the period in which Sirius, “the dog star,” rises in conjunction with the sun.

We are told that some ancient types believed that the added heat of Sirius contributed to making conditions more oppressive. (Siriusly?)

In any event, we are confident that persistent high pressure centered over the North Pacific has been a bigger factor than Sirius this summer.

Officially, July finished slightly below normal in Philadelphia, and nationwide, it was the coolest since 2009.

As for the first three weeks of August – and we thought we’d take a look at them before we go on a hiatus of our own -- the temperatures have been so consistently below normal in the region that we looked back to find the last time it was this cool.

Once again, we learned that weather memories can be short. The first three weeks of August last year actually were cooler.  

The average temperature for the Aug. 1-21 period this year is going to come in close to 74.7 at Philadelphia International Airport, compared with 74.1 in the same period last year.

Among the last 30 years, which have been on the warm side, this was No. 5 on the Aug. 1-21 coolest list. Again, we were surprised that it didn’t rank a little higher.

The coolest of the recent periods was  1992’s – 72.8 – the year that the world was being chilled by the aftermath of the Mount Pinatubo volcanic eruption.

Looking ahead, the Climate Prediction Center sees some signs that the Pacific high-pressure pattern in the West is breaking down, and that could allow some heat to return  next week.