Climate Change Chart of Honolulu, USA

Overview of climate changes

Temperature changes

Monthly mean temperature was higher by a difference of +0.85 °C averaged across calendar months in the more recent reference period; this unweighted comparison describes the set of monthly averages, not a continuous trend or the temperature on every day. The largest monthly mean temperature increase was in September, with a difference of +1.10 °C; this identifies the strongest increase among the supplied monthly comparisons, rather than a change in daytime highs.

Changes in rainfall

Mean daily rainfall was lower by a difference of -0.37 mm/day averaged across calendar months, but this does not mean every month was drier or establish how often rain fell.

Changes in rainfall

The largest monthly decrease in mean daily rainfall was in January, at a difference of -2.06 mm/day; this is a daily mean, not a monthly rainfall total. By contrast, mean daily rainfall increased in March by a difference of +0.20 mm/day, illustrating that the overall average difference does not describe each month's direction.

Changes in sunshine duration

Mean daily sunshine duration was lower by a difference of -0.22 hours/day averaged across calendar months, a comparison of monthly daily averages rather than a guarantee of sunshine on any particular day. The largest monthly sunshine decrease was in March, with a difference of -0.49 hours/day; the change concerns mean daily hours and does not determine the conditions of an individual visit.