Last Thursday, April 23, Fargo Moorhead recorded the first 70 degree day of the season. The long term average for the first 70 is on April 18, so even with the persistently cold weather this spring; we did manage to hit that milestone around the normal date.
But not only did we record our first 70 of the season last week, but also our first 80, as the official high on Thursday was 82 degrees. The average first 80 degree day of the season is on May 5, therefore earlier then the seasonal average. You may ask yourself, “how unusual is it to hit 80 without a previous day in the 70s”? 2009 was only the 11th time since 1881 that the first 70 degree day of the season happened to be a temperature of 80 degrees or higher. The last such occurrence was back in 1996 with a high of 83 degrees on May 15.
Wow Daryl! How do you know all of these facts? Very impressive. My visit to Fargo/Moorhead was a good one and learned a lot and specifically very impressed how the flood effort was done. Kudos to city of Fargo for what I saw there!
Daryl,
I know you give Fargo stats for data about “first” dates and “last” dates, and I use Grand Forks data for my studies and amusement, but in the end they are very similar. With my newfound interest in temperature standard deviation, it’s amazing how close the date of the “first 70″ (or any milestone) matches to the date when the average temperature + 1 standard deviation equals 70. For instance, the date when the Avg. + 1 SD = 70 for GF is April 19th (Compared to your April 18th). That date for 80 is May 8th in GF(compared to your May 5th). The Fargo date may historically be a day or two earlier, too. I’ve also noticed that first/last freeze maps correspond very closely to the Avg Temp +/- 1 SD = 32 (May 7 in spring, Sept. 23 in fall).
Dustin,
Much of my work has been with the Fargo data, but I would love to see some of your statistical work for Grand Forks. If you don’t mind sharing you could send it too me at dritchison (at) wday.com.