Some statistics as we 'ease into fall'
Posted September 27, 2016
Last week, as we were heading toward the traditional start of fall with the passage of the Autumnal Equinox on Thursday at 10:21 a.m., Nate Johnson put together a nice graphical summary of some temperature and precipitation-related statistics that Greg Fishel presented a couple of times on the air.
We've had a few follow-up requests asking about the availability of those graphics and that collection of statistics, so I thought I'd post it here so that anyone interested would have a place to find it for reference.
The first of the two images gives a rundown on the long-term average dates for several seasonal markers of interest, like the average last date with a high reaching 90, or 70, and the average first date with a freezing low temperature.
The second image is similar, but addresses extremes rather than averages - for example, the latest date we've seen 80 degrees or higher, and the earliest we've had freezing temperatures or a first snow.
A couple of these warrant a bit of explanation. The dashes ("---") for "Last 70-degree Day" are an indicator that there is no day during the entire year that we haven't reached 70 or higher at least sometime in history. In addition, you'll see two dates in the panel for "First Snow."
For the Raleigh area, the earliest recorded trace of snow (meaning snow was observed but there was not enough to measure) was on Oct. 24, while the earliest measurable snow (at least one-tenth of an inch or more) occurred on Nov. 6. The January average first snow date refers to measurable amounts.