A Hot September...
Posted October 1, 2007
We finished up another toasty month at the RDU airport yesterday, and while we we certainly had a few interludes of fresh, fall-like air during the month, it did close out with temperatures well above normal, and in fact the average temperature for the month (75 degrees) was the second highest on record for RDU, among readings that date back to 1944. September of 2005 was the only hotter month for the airport, with an average temperature that year of 76 degrees (I missed out on that one, but experienced plenty of hot weather that September at Camp Arifjan, Kuwait), and you have to go back to 1980 for the last occurence of the number three value of 74.9 degrees. It is worth noting that if you include earlier readings for "Raleigh" before the airport became the station of record, 1921 gets honors for the hottest September, averaging 78.5 degrees.
September this year brought 14 days with highs at or above 90, compared to a normal of three for the month, and we cracked the century mark on the tenth with a high of 101. The 90-degree day total for the year is now up to 80 days, way above the old RDU record and just two shy of the Raleigh record (from 1941) of 82. It appears we'll warm up some later this week, but for now the chance of reaching 90 again looks fairly small though we certainly can't rule it out.
One additional point on the heat this year. It turned out that climatological "summer" (June 1 through August 31) at RDU was the hottest ever at 79.8 degrees. A climate summary that stated 80.3 degrees for RDU back in summer 1952 as the top value turned out to have used numbers from a different location and not from the airport. In addition, Dr Chip Konrad, the deputy director of the Southeast Regional Climate Center, which recently relocated from South Carolina to Chapel Hill, sent an interesting e-mail pointing out that if one ignores arbitrary dates and uses a sliding 90-day window to look for the hottest three-month period of the year, we averaged a very hot 80.9 from June 17th through September 14th this year. He noted that on average, our hottest 90-day stretch lags the traditional "meteorological summer" of June through August by about eight days or so. In addition, he sent a link for a very cool web site he and a colleague have put together to generate a great variety of weather records, slicing and dicing the data for several cities around the state and region in a number of interesting ways. Some of you might enjoy perusing the site, so here's the address: