Port Stanley Weather Records (CA006136694)

The fitted trend in annual mean temperature here over 1875 to 1983 is -0.02 C (-0.07 to 0.03) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: -0.04 F (-0.13 to 0.05) per decade. The slope is a straight line fitted to 72 complete years; the brackets give its 95 percent interval.

Across 72 years with a frost, the median last spring frost at Port Stanley falls on 14 May and the median first autumn frost on 8 October, which leaves a median of 148 days between them.

In 1918 to 1983 the median growing season was 146 days. That is 4 days fewer than in 1875 to 1905.

Fitted over all years, the growing season changes by -0.4 days per decade at this station.

A day with at least 45.2 mm (1.8 in) of rain is expected about once in 2 years. A day with at least 89.5 mm (3.5 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, 79 years of values from 1872 to 1983.

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: 83.8 mm (3.3 in) in 1967; 83.8 mm (3.3 in) in 1968; 81.5 mm (3.2 in) in 1961.

One change was suspected in the annual mean temperature of Port Stanley, at 1894. Each is measured against neighbouring stations.

• Relative to 5 neighbouring stations, the station's annual mean temperature from 1894 ran 0.4 C (0.8 F) lower than in the years before (likely change).