Summer 2011 Heat Records Crushing Cold Records by 13 to 1

For related record temperature posts, see:

• Record Heat
• Record Cold

After narrowly exceeding cold records in May, U.S. heat records in the first 9 days of June have outnumbered cold records by an eye-popping ratio of 13 to 1. For the year 2011 to date, the ratio is a more modest, but still impressive, 2.2 to 1. The cumulative excess of heat records over cold records since January 2010 is over 10,000. Since March 2010 there has been only 1 month (December) with more low temperature records than high temperature records.

Although June temperatures to date have been particularly cold in California, they have been warmer than average nearly everywhere east of the Rockies.

Images (click to enlarge):

• Monthly total number of daily high temperature and low temperature records set in the U.S. for June 2010 through June 9, 2011, data from NOAA National Climatic Data Center, background image © Kevin Ambrose (www.weatherbook.com). Includes historical daily observations archived in NCDC's Cooperative Summary of the Day data set and preliminary reports from Cooperative Observers and First Order National Weather Service stations. All stations have a Period of Record of at least 30 years.
• Cumulative excess of heat records vs. cold records by month for 2010 and 2011 to date, data source as above
• Preliminary June 2011 to date monthly temperature departure from climatological average from NOAA/NCEP via ESRL