Saturday, May 23, 2015

Summer of 2011, another hot one

The June 1-Aug. 31 period will rank No. 5 on the all-time list.

Summer of 2011, another hot one

The final numbers won't be in until after midnight, but the summer of 2011 appears to be the fifth-warmest in Philadelphia's 138-year period of record, with an average temperature of 78.

Tha'ts based on the preliminary math by Mark DeLisi, the climatologist at the National Weather Service in Mount Holly.

DeLisi also notes that nine of the 10 warmest summers have occurred since 1991, and he is certain that's more than coincidence.

The odds of that happening randomly are less than 1 in 1,000, he says.

Whether humans are to blame or the fall-out from Sputnik or a natural process, the world has become warmer in recent decades.

Certainly, Philadelphia summers have become warmer. Here is the top 10 list from DeLisi:

2010 -- 79.6

1995 -- 78.6

1994 -- 78.3

1993 -- 78.2

2011 -- 78.0

1991 -- 77.9

2005 -- 77.8

2002 -- 77.7

1999 -- 77.2

1900 --- 77.2


Inquirer Weather Columnist
About this blog

Everyone talks about the weather, and here we write about it.

When we’re around and conditions warrant, we’ll keep you updated about what’s coming, but we will do our best always to discuss weather and climate developments in context and remind you that nothing in the atmosphere happens in a vacuum.

Tony Wood has been writing about the atmosphere for The Inquirer for 26 years.

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