Autumn in Richmond

It feels like every time I go outside over the past month, I'm struck by the gorgeous, autumnal weather. My Yankee family turned south in 1994, and while we love our adopted home state, we've always missed what seems like clearer seasonal changes above the Mason-Dixon line. So it is that, following what seemed to be a mild summer, I've really appreciated a rare, proper autumn in Richmond, Virginia.

But is it really that rare or different? What is it about this weather that brings me back to cool autumn days walking through Delicious Orchards in New Jersey, picking apples? I decided to waste some time number-hunting to see whether data backed up my subjectivity (all of which came from Wolfram Alpha). And I made a chart:

Why October? That's the month where we really start to feel the transition out of summer into milder weather. I was able to pull the average high and low temperatures in Richmond for each October since my family moved to Virginia. Rather than the overall average, I went with the high and low so I could include the range. Basically, could I wear a hoodie in the morning? Was it t-shirt-and-shorts weather later in the day? Then I started thinking about how, in these temperature ranges, humidity starts to behave differently, contributing to a perceived chill in those cool mornings where it might have felt stifling on warm afternoons. I stuck with the average low humidity because I figured that would give a sense of how dry the month felt.

As I collected and examined these data points, two problems came into focus. First, my memory must be pretty bad and more subjective than I already suspected because, really, look at the chart. October hasn't changed dramatically in Richmond over two decades, at least for these metrics. And that leads me to the biggest problem - trying to fit my subjective experience of fall to collection of metrics.

The more I thought about these numbers, the more I wondered what other factors might explain how I felt about the weather. Did I need to look at the preceding few months for each year to see whether there was a dramatic relative difference? What about cloud cover? Wind? Precipitation (and storms vs. drizzle)? How much time did I spend outside, and did those days happen to be when the weather was pleasant?

I suppose what I'm really saying here is that I should be outside enjoying the autumn sunshine instead of staring at a screen researching tenuously connected data points :-)