Climate Change Chart of Vail, USA

Overview of climate changes

Changes in snowfall

Mean daily snowfall increased on average across calendar months, with a difference of +3.32 mm/day compared with the earlier reference period. This is an unweighted average of monthly means, not a day-weighted annual figure; it describes an aggregate and does not indicate that snowfall rose in every month. The largest monthly increase was in December, a difference of +6.80 mm/day. The largest decrease occurred in September, a difference of -0.03 mm/day; both figures refer to mean daily amounts rather than monthly snowfall totals.

Temperature changes

Monthly mean temperatures were higher on average across calendar months in the more recent period, with a difference of +1.83 °C. This is an unweighted average of the monthly means, not a day-weighted annual figure, and it does not imply that every month was warmer. January had the largest monthly increase, a difference of +3.95 °C, while October recorded the largest monthly decrease, a difference of -0.16 °C. These figures describe monthly mean temperature, not daytime highs, and mark the largest changes in each direction rather than a uniform pattern across months.

Changes in rainfall

Mean daily rainfall decreased on average across calendar months, with a difference of -0.10 mm/day compared with the earlier reference period. This is an unweighted average of monthly means; it does not mean rainfall fell in every month, and the values describe daily means rather than monthly totals. The largest monthly decrease occurred in May, a difference of -0.45 mm/day. By contrast, July had the largest monthly increase, a difference of +0.13 mm/day, showing that the average change across months does not capture every month's direction.

Changes in sunshine duration

Mean daily sunshine duration was lower on average across calendar months in the more recent period, with a difference of -0.37 hours/day. This unweighted average of monthly means is not a day-weighted annual average and does not establish that sunshine declined in every month. February saw the largest monthly decrease, a difference of -0.82 hours/day. That identifies the strongest decrease among the supplied monthly differences, not a general measure of every month's change.