This is one that’s been gnawing at my brain for some time.
A criticism we sometimes face is making a big deal out of routine weather, acting as though something that happens often is noteworthy or dangerous. Here’s the problem: it can be. And is.
Take a recent study that showed that falling precipitation increases the likelihood of a fatal vehicle crash by 34% (Stevens, S., C. Schreck, S. Saha, J. Bell, and K. Kunkel, 2019: Precipitation and fatal motor vehicle crashes: continental analysis with high-resolution radar data. Bull. Amer. Meteor. Soc. doi:10.1175/BAMS-D-18-0001.1, in press). 34% is a huge uptick! They also found that precipitation intensity increases the risk, precipitation-related crashes peak in the morning, and that the risk is higher in winter. More pertinent to me, since I work in Iowa, is that their Upper Midwest geographical area had the second-highest relative risk out of nine geographical areas.
Anecdotally – I don’t have hard evidence for this – it seems that we have more issues with vehicle crashes for low-end snowfall events (say, less than three inches) than for higher-end events. If this is the case, I would assume it’s at least partly due to the fact that, for low-end events, most people go about their usual business and so the traffic volume is the same despite more inherently dangerous travel conditions, thus the number of wrecks goes up. Meanwhile, for higher-end snowfalls, more people adjust their work situation if they are able, and so there are fewer vehicles on the road to end up getting in a crash in the first place.
And so we have this issue that confounds me: how to message the threats associated with seemingly normal “low-impact” events because they’re light and occur frequently, and so we should be used to them.
I feel that the “Alert Days” that many TV stations do try to address that. There’s no shortage of concern or even hatred over these, and while some of the arguments are valid, I feel that they at least try to highlight the threats that do exist even when the weather is not outside the norm. Unfortunately, I also think that these “alert days” are meant to be a panacea of some sort when this whole situation is really nuanced and complicated.
On a related note, how do we define “impact”? If my theory that we have more vehicle crashes in low-end snowfalls compared to high-end ones, does that mean that the former should be considered higher impact? On the flip side, those same higher-end events result in school cancellations, business closures, etc. So they’re still high-impact from that standpoint. Is there a way that “impacts” can be differentiated? Are school closures a “soft” impact compared to a vehicle crash? And if so, would those who have to take off work to care for their child(ren), and possibly lose a day’s worth of pay, also consider the impact “soft”?