June rains: Record puzzle
Second wettest June on record, but where are the floods?
On this date 10 years ago, heavy rains pounded the region during what turned out to be one of the wettest Junes on record.
Where it meets the Schuylkill, the Wissahickon Creek sloshed over its banks that evening, and the Schuylkill, itself, went above flood stage for over 10 hours, starting at 2:45 a.m.
Three years later, at the end of another near-record wet June, a spell of rain that lasted from the 23d to the 28th, resulting in widespread flooding and forcing the evacuation of 70 households in Manayunk.
We mention those two Junes because one difference between them and this one is that June 2013 actually has been wetter.
So far, officially, 8.31 inches of rain has been measured at Philadelphia International Airport, making this the second-wettest June on record, behind only the 10.02 of 1938.
Various research has linked worldwide warming to heavier rainfall. For what it's worth, three of the five wettest Junes in the 142-year period of record in Philadelphia have occurred in the last decade.
No. 3 on the hit list is 2003, at 8.08 inches, and No. 5 is 2006, 7.95.
We have had more than our measure of nuisance flooding this month, but the June has been wetter than both 2003's and 2006's, why has the region avoided major flooding?
A few reason:
--Coming into June, rainfall for the previous four months was below normal.
--That said, rainfall was adequate enough, and heat sparse enough, to allow the foliage to thrive and drink up the copious rains when they came.
--It has rained a whole lot harder around here than it has near the river headwaters to the north.
In 2006, areas to the north got hammered. In 2003, rainfall coming into June was well above normal.
Yes, it's been quite wet, but overall, in terms of flooding the region has been quite fortunate.