Oxthoc Weather Records (MXN00015064)

The annual mean temperature here has fallen by 0.13 C (0.02 to 0.24) per decade over 1961 to 2005. In Fahrenheit: 0.23 F (0.03 to 0.43) per decade. The slope is a straight line fitted to 40 complete years; the brackets give its 95 percent interval.

Across 33 years with a frost, the median last spring frost at Oxthoc falls on 26 February and the median first autumn frost on 16 November, which leaves a median of 262 days between them.

Fitted over all years, the growing season changes by -0.6 days per decade at this station.

A day with at least 51.3 mm (2.0 in) of rain is expected about once in 2 years. A day with at least 81.9 mm (3.2 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, 43 years of values from 1961 to 2006.

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 2005; 75.9 mm (3.0 in) in 1978; 72.9 mm (2.9 in) in 1998.

2 changes were suspected in the annual mean temperature of Oxthoc, at 1977 and 1998. Each is measured against neighbouring stations.

• Relative to 5 neighbouring stations, the station's annual mean temperature from 1977 ran 0.3 C (0.5 F) higher than in the years before (likely change).
• Relative to 5 neighbouring stations, the station's annual mean temperature from 1998 ran 0.6 C (1.1 F) higher than in the years before (likely change).