This article summarises the literature available on weather impacts on road accidents and casualties as well as discussing the main weather trends seen since 2010 and their likely impact on road casualties. We are carrying out more detailed research looking at the relationship between weather events (such as rain or sub-zero temperatures) and casualties. The key findings from this article include: *As the number of road casualties gets smaller, understanding the reasons behind year-on-year changes becomes more important. Weather patterns provide useful context to explain year-on-year changes in road casualty statistics. *Significant and extended snowfall throughout Britain at the start and end of 2010is likely to have suppressed the number of users on the road leading to a reduction in traffic, accidents and casualties in these periods. This is likely to have reduced the number of fatalities in 2010 and as a result an increase in fatalities was seen in 2011. The return to the long term downward trend in fatalities in 2012 and 2013 after the increase between 2010 and 2011 reinforces the hypothesis that the 2010 figures were affected by the weather. *2012 was the second wettest year on record. The likely result of this additional rainfall in 2012 would have been to reduce the number of vulnerable road users, particularly pedal cyclists and motorcyclists on Britain’s roads, especially during the spring and summer months. This may have had the effect of reducing the number of accidents and casualties from these user groups. Both 2011 and 2013 were drier than 2012 so some caution is needed in interpreting changes in casualties between years over the period 2011-2013. (Author/publisher)
Abstract