Wet start to 2016

Bunbury has recorded its second wettest January in the past 20 years while the average overnight temperature was the third highest for any month during the same period.

Bunbury had 51mm of rain last month, with only 2011 experiencing a wetter January since the Bureau of Meteorology's official Carey Park site started being used in 1995.

The BoM site experienced technical issues last month, which meant nearly three days of temperature and rainfall data were not recorded.

A BoM spokesman confirmed rainfall data from a back-up Bunbury site was being used in their official January figures instead.

The site's outage coincided with the month's heaviest rainfall, which also dumped record rains on southern areas including Pemberton.

Bunbury experienced six days of rain last month with 38.2mm posted between January 20 and 21.

In contrast, there was no rain in Bunbury during January last year.

Last month's average minimum temperature of 17.9C was the second highest recorded for January at the BoM site, only behind the 18.1C in 2012.

February 2011, with average minimum temperatures of 18.6C, was the only other month since 1995 with warmer nights.

While three minimums from last month were not recorded, the data is still recognised by BoM and included in its averages.

Last month's warmest night was 25.4C on January 8 while the coldest was on January 13 when the temperature dropped to 10.8C.

The 17.9C average minimum was 2.5C above the long-term average while the 31C average maximum last month also exceeded the long-term figure of 29.8C.

January's warmest day was the seventh with a maximum of 38.7C while the coolest day came at the end, with the January 31 maximum only reaching 21.1C.