There has been plenty of talk about this being The Year Without a Summer across the United States, but this discussion is much more about perception than reality–as the June 2009 temperature statistics (temperature anomalies) indicate. (NOTE: For a preview of the forecast for the upcoming winter, see Snowy, Cold Winter on the Way?)
Here is map, from the National Climatic Data Center, indicating temperature departures from average across the United States in June 2009. The areas in blue were cooler than average, and the areas in red were warmer than average. While much of the country was, indeed, cooler than average (the darker blue areas were significantly so), much of the country was also warmer than average (the brighter red areas were significantly so).
Temperatures anomalies across the United States in June 2009; image from NCDC
Perception of Cool Summer
The perception that it’s been an exceptionally cool summer across the United States is because the areas that have been cooler than avearge are more the more populated areas.
The coolest areas relative to average have included:
- Boston
- New York
- Philadelphia
- Baltimore
- Washington
- Chicago
- Los Angeles
- San Diego
Cities that have been hotter than average include:
- Seattle
- Nashville
- Charlotte
- Dallas
- San Antonio
- Atlanta
- Jacksonville
- Miami
While there are large cities in the hotter-than-normal list, it’s clear that the cities on the cooler-than-normal list are more significant in terms of population and media attention (with my apologies to Atlanta, the home of the Atlanta Channel, I mean Weather Channel).
Reverse the Map
If we were to reverse the areas on the map–imagining the cooler areas as hotter than normal and warmer areas as cooler than normal–then the perception would also be reversed. If it had been significantly hotter than normal from Boston to Washington and in Southern California, we’d be talking about the unending summer right now.
I’ll talk more about temperatures for specific cities after the July statistics have been tallied–it will be deeper into the summer, the weather can change by then, and we’ll have more numbers to look at.
–Paul Yeager
