The average monthly temperature last month was 1.7 degrees warmer than average, according to statistics from the Southeast Fire Centre.
The amount of rain recorded at the Castlegar airport was 85 per cent of normal.
"A few weak disturbances produced minor showers at times but high pressure was more dominant and maintained the generally dry and unseasonably warm pattern of April through the initial 18 days of May," forecaster Ron Lakeman wrote.
Record daily high temperatures of 28.4 and 29.7 degrees were set on the 2nd and 3rd respectively. The warmest temperature of the month was 30.2 degrees during the afternoon of the 7th. The all-time hottest temperature for the month in Castlegar was 34.5 degrees on May 18, 2006.
The lowest temperature last month was 2.2 degrees on the 10th. The all-time low of minus-4.7 was set on May 1, 2013.
"The final two weeks of the month were much wetter and more seasonal temperature wise as a series of Pacific systems pushed across southern BC with frequent showers and thundershowers," Lakeman said.
Overall we received 60.1 mm of precipitation compared to the usual 70.3 mm.
Ninety-five per cent of the month's total rain fell during this period. The more significant amounts were recorded during the late afternoon and night of the 18th, the Victoria Day long weekend, and on the 26th and 27th.