Image (click to enlarge): Frequency of 1" or more of snow in Washington, DC by date in February, 1930-2007, CapitalClimate chart from NWS data
Much attention has been given in the global warming deniosphere to rare events such as the recent UK snows and an all-time record low temperature in Maine. Aside from the facts that
- snow doesn't necessarily correlate with temperature
- climate is a long-term average in which all of the extremes are reduced to a small residual,
Clearly, by late February the average temperature trend has begun to turn upward, but what is the effect on snow chances? The chart shows the frequency of 1" or more of snow falling on any given date in February over the last nearly 80 years (1930-2007) in Washington. The peak of 9 occurrences occurs near the middle of the month on the 11th, but the preceding and following days have frequencies of 2 and 3, respectively. On the other hand, by the end of the month, snow has been observed 5 times on the 28th, which is 5 times as often as the mere 1.4" which fell on Feb. 21, 1993.