Hangzhou Weather Records (CHM00058457)

The annual mean temperature here has risen by 0.3 C (0.2 to 0.3) per decade over 1951 to 2012. In Fahrenheit: 0.5 F (0.4 to 0.6) per decade. The slope is a straight line fitted to 62 complete years; the brackets give its 95 percent interval.

Across 60 years with a frost, the median last spring frost at Hangzhou falls on 28 February and the median first autumn frost on 6 December, which leaves a median of 280 days between them.

In 1981 to 2012 the median growing season was 295 days. That is 21 days more than in 1951 to 1980.

Fitted over all years, the growing season changes by +5.3 days per decade at this station.

A day with at least 85.9 mm (3.4 in) of rain is expected about once in 2 years. A day with at least 183.8 mm (7.2 in) of rain is expected about once in 100 years.

The levels come from a generalised extreme value (GEV) distribution fitted by L-moments to the wettest-day total of each year, 66 years of values from 1951 to 2023.

A return level is an estimate. It is least reliable for the long periods, 50 and 100 years, and for any period longer than the record behind the fit, where the fit has to reach past the largest day actually observed. It is not a forecast.

The largest wettest-day totals in the fit: 191.3 mm (7.5 in) in 2007; 189.3 mm (7.5 in) in 1963; 157.2 mm (6.2 in) in 1962.

2 changes were suspected in the annual mean temperature of Hangzhou, at 1968 and 2003. Each is measured against neighbouring stations.

• Relative to 4 neighbouring stations, the station's annual mean temperature from 1968 ran 0.2 C (0.3 F) higher than in the years before (likely change).
• Relative to 4 neighbouring stations, the station's annual mean temperature from 2003 ran 0.4 C (0.8 F) higher than in the years before (likely change).