July heat is elite

We still have a ways to go, and the temperature forecasts for the rest of the month will show some fluctuation.

The temperatures on this anomalously magnificent day -- dewpoints are in the 40s, and the brilliant blue sky is almost water-vapor free -- will cool the monthly temperature a tad. 

But we've seen enough already to declare that when it all ends next Tuesday, July 2012 almost certainly will become one of the warmest five months in Philadelphia in the period of record, dating to 1874.

Based on the National Weather Service forecast, July would finish at 81.8 degrees Fahrenheit, good for No. 3 on the all-time list.

What jumps out at us is the fact that assuming this holds up, three of the of four warmest months in the last 139 years will have occurred in the last three summers.

The official readings at Philadelphia International Airport no doubt have been affected by increasing urbanization.

But before 1940, the readings were taken at four different locations in Center City in settings that weren't exactly pastoral.

July 2011 remains the warm king at 82.4, followed by July 1994, 82.1. The current No. 3, the one in danger of losing its exalted perch, is July 2010, at 81.7.

All the months on the top 12 list, including this one, are Julys, as well they should be. No. 13 would be August 1980, at 79.9.

Augusts just can't complete for the top spots because the hours of daylight become ever shorter.

As for Junes, true, June is solstice month, but it takes a few weeks for the solar heating to peak.

The warmest June on the list, 2010, at 78.2, is only No. 45 among the 415 months (including this one), on the official records.

In the meantime, we would be only too happy to bottle this afternoon and forget about any records.