College Football Climatology: 2015 Update
Posted on September 3, 2015
After a couple years that have seen some additional FBS conference re-alignment, I felt it was time to update my original college football climatology, which you can access here. The first version was published at the beginning of the 2013 season. This post will not be another comprehensive summary on the methodology or analysis, as was posted in that version, because the vast majority of it still applies.
What exactly were the changes that prompted this update? Here’s a brief summary.
- Tulane now plays in an outdoor stadium, after it had previously played in the Superdome. Therefore, it was originally excluded from the climatology.
- Although UAB briefly discontinued their program, news reports say that it will be brought back. I have assumed that they will remain in Conference USA.
- Maryland and Rutgers moved to the Big Ten.
- Louisville moved to the Atlantic Coast Conference (ACC).
- East Carolina, Tulsa, Navy, and Tulane moved to the American Conference.
- Old Dominion and Western Kentucky moved to Conference USA.
- New Mexico State moved to the Sun Belt.
As I explained in my original post, the average maximum temperature of each stadium location will be most representative to compare cold and warm locations, rather than simple average temperature. This is just because most college football games are played during the daytime or the early evening hours – some of the warmest times of the day on average. The average temperature takes into account the daily low, which often occurs right around sunrise; other than some dedicated tailgaters or people attending College GameDay, there is usually not a whole lot going on at that time of day.
Even accounting for the teams changing conferences, the overall distribution of the combined average maximum temperatures of the conferences remained relatively consistent with the previous climatology. The Mid-American Conference (MAC) and Big Ten remained the coldest by a considerable margin, and Conference USA and the Sun Belt Conference remained the warmest.
This is largely due to geography, as you can see on the map displayed above (plotted using Tableau). The MAC, and to a slightly lesser extent the Big Ten, is very concentrated around the Great Lakes with less spatial distribution than some other sprawling conferences that have some individually cold locations (such as the Mountain West). More frequent cold fronts and a higher latitude favor colder conditions in those regions. Meanwhile, the Southeastern Conference (SEC) is largely concentrated in the southeastern United States (duh!), but so too are the Sun Belt and Conference USA. Those three conferences overlap quite a bit geographically, and therefore they are the three warmest on average.
Recommended: Interactive Map
You can access an interactive version of the above map on Tableau by clicking here. When you arrive at the interactive map, you can click on the bar graph on the right hand side to filter the map by conference, as well as sample the values.
Another Tableau map plot, included below, makes it easy to see the precipitation trends across the country during college football season. The size of the bubbles on the map correspond to the average total precipitation from September to November. The locations with the higher averages are generally east of the Mississippi River and in the Pacific Northwest. The locations with the lower averages are concentrated in the desert Southwest.
The shading of the bubbles, however, indicates the average total number of days with at least 0.25 inches of precipitation. To put it another way, bigger bubbles indicate “rainier” locations and greener bubbles indicate locations that receive a soaking rain more frequently. There can obviously be some overlap, such as in south Florida – there tends to be a lot of rain from September to November and it occurs more frequently than a lot of other FBS locations. However, this map also allows you to tease out differences between locations with similar average rainfall.
Consider Seattle, Washington and Dallas, Texas, homes of the Washington Huskies and SMU Mustangs respectively. They average nearly the same amount of precipitation during college football season (10.77 and 10.51), but Seattle averages over four more days with at least 0.25 inches of precipitation. This is a great example of how just looking at total precipitation will not tell you the entire story.
Recommended: Interactive Map
You can access an interactive version of the above precipitation map on Tableau by clicking here. You can filter the data by total precip or number of days with at least 0.25 inches of precip.
And finally, we will wrap up with snow. In general, the most likely locations for a snowy college football game are situated along the front range of the Rocky Mountains – including Air Force, Colorado, Colorado State, and Wyoming. After that the next most likely locations include the teams in northern Utah, as well as the Great Lakes region.
In the above map, the size of the bubbles corresponds to the average amount of snow from September to November, whereas the shading becomes a deeper blue with a greater average number of days with at least 1 inch of snow in the same time period. The University of Colorado in Boulder has the greatest average snowfall in college football season, with 20.8 inches. While Colorado and Wyoming are neck-and-neck for the average number of 1-inch snowfalls, Wyoming has the greatest average number of snowy days (at least 0.1 inches of snow, or measurable snow) although that is not reflected in the map.
College Football Top-10 Extremes (Added: Sep 4th)
In the spirit of college football, here are some rankings of the warmest, coldest, rainiest, driest, and snowiest locations in the Football Bowl Subdivision (FBS). Although these lists were included in the original climatology, I have reproduced some of them here for completeness. The rankings have stayed the same with the addition of Tulane to the database, now that they are playing outdoors, with one exception. Tulane ranks as the 10th warmest location by average temperature. However, as I explained above, the rankings below for warmest location are based on the average maximum temperature as that is more representative of when football games are played. Remember, these values are representative of a September to November climatology only.
The list of most “rainy days” changes slightly if you use a 0.25 inch threshold, rather than just a 0.01 inch threshold. In some ways, the higher (0.25 inch) threshold could be more representative of the frequency of days when there is a soaking rain at some point, whereas the lower threshold may capture brief or very light rain events that have very little impact. You can compare these Top 10 lists below.
Finally, here are a couple Top 10 lists of snowy college football locations, which didn’t appear in the original climatology.