Climate Change Chart of Jackson Hole, USA

Overview of climate changes

Temperature changes

Averaged across calendar months, monthly mean temperature shows a difference of +1.47 °C compared with the earlier reference period; this is an unweighted mean of monthly means, not a day-weighted annual average or a measure of daytime maximum temperatures. The strongest monthly increase was in January, with a difference of +3.05 °C. By contrast, October had the largest monthly decrease, a difference of -0.15 °C. These monthly contrasts describe reference-period averages, not changes in every individual year.

Changes in snowfall

Mean daily snowfall averaged across calendar months had a difference of -0.86 mm/day compared with the earlier reference period; this is an unweighted average of monthly means, not a day-weighted annual total. The largest monthly decrease occurred in November, with a difference of -3.87 mm/day, while February had the largest increase, a difference of +2.26 mm/day. These refer to average daily amounts in the named months, not monthly snowfall totals or conditions in every year.

Changes in rainfall

Mean daily rainfall averaged across calendar months shows a difference of +0.07 mm/day between the reference periods, rather than a change in monthly totals; the mean is unweighted across calendar-month means. The largest monthly increase occurred in September, with a difference of +0.63 mm/day, while June recorded the largest decrease, a difference of -0.66 mm/day. These are differences in average daily amounts for the named months, not a claim that rainfall changed in the same direction in every year.

Changes in sunshine duration

For mean daily sunshine duration, the unweighted mean difference across calendar months was -0.22 hours/day. This summarizes monthly averages, not a day-weighted annual figure. The largest monthly decrease was in April, with a difference of -1.06 hours/day; in November, the largest increase was a difference of +0.28 hours/day. The month-specific differences show that the comparison varies by month and do not describe every individual year.