What happened in February

I have to admit what first caught my attention when I sat down to write this was the string of amazingly cold temperatures across the United States in February. While inputting data on a daily basis for the Forecast Earth Temperature Index -- a table measuring the daily average temperatures of 50 American cities against their historical averages -- it was hard not to notice.

To say the least, the middle of the country endured a frosty February, with 15 Index cities posting six or more days of average temperatures 10.0 degrees or more below their historical averages -- as compiled by the National Climate Data Center (NCDC) Daily Normals (1971-2000).

Madison, WI, topped the list, posting 12 days of average temps -10.5 degrees or more, with the average reaching 26.5 degrees below on February 10. Des Moines dealt with 11 days of average temperatures -10.0 degrees or more, while Kansas City and Sioux Falls, SD, each posting 10 such days.

On February 20, things got particularly harsh, with Sioux Falls checking in 31.5 degrees below the city's historical average. In Des Moines, the average temperature fell -29.5 degrees (vs. historical average), while in Kansas City, temperatures fell to -25.5 degrees.

Add to these cold spells unprecedented snowfall across the country, and it prompts articles like this one by Andrew C. Revkin in Sunday's New York Times.

A closer look reveals something a little different. According to the Temperature Index, there were more days in February 2.0 degrees above their historical counterparts than days 2.0 degrees below. Among the 1,450 measurements for the month, 689 days (48 per cent) posted in the +2.0 or more category, while only 556 (38 per cent) were -2.0 or more.

While the cold temperatures received the bulk of attention in February, several cities were swept by unseasonably warm temperatures. San Antonio, TX, saw 17 days +6.0 or more. Charleston, SC, posted 15 days of temperatures +6.5 or more, with Washington, DC, recording 13 days of temps +9.0.

Climatologists will spend quite a bit of time explaining the extraordinary February the United States has just endured. Unfortunately, any sign declaring a break in the recent warming trend, when viewed in the bigger picture, has an equally strong sign indicating the complete opposite.