U.S. Climate Extremes Index
By Paul Homewood
As part of their US Climate Extremes Index, NCDC run one for “Days with/without precipitation, as shown above.
They define it as
“The sum of (a) percentage of the United States with a much greater than normal number of days with precipitation and (b) percentage of the United States with a much greater than normal number of days without precipitation.”
A simple average of rainfall statistics may show a “normal year”, but could hide the fact that half the country is in drought, and the other half suffering floods! This index attempts to get around this problem, although it does not quantify rainfall amounts, simply rain days.
Nevertheless, it gives a good overall picture of what was happening last year. Far from the claims of extreme weather, that we are used to hearing from Katharine Hayhoe and co, 2012 was remarkably, well, unremarkable!
Days without rainfall were pretty much normal by historical standards, while areas with more wet days than normal were well below normal.
It is also noticeable that the extremes of both types, that were seen regularly in the past, have not been a feature in recent years.