More than 200 readers entered our game to forecast the number of days that will reach 90 or higher at Reagan National Airport between May 1 and October 15. The average number predicted was 42 (also the median).
This number is slightly lower than Capital Weather Gang’s prediction of 45-50. The range of submissions spanned 4 to 105. Since 1980, the most 90+ days to occur was 68 in 1980 and 2010, and least was 11 in 2004.
The above chart displays a histogram which gives a good general sense of the grouping of predictions.
Interestingly, reader forecasts had a tendency to fall into a range either just above (41 to 50) or below (21-30) the historical average number of 90+ days, rather than average itself - which is 36 (or between 31-40).