November marked the beginning of a weak El Nino event that resulted in slightly above normal temperatures for the Chemainus Valley, a more pronounced spike in sunshine and rainfall that was a little more than 20 millimetres below normal.
“In general, most of the sunny and mild weather occurred during the first half of November when El Nino was strongest and most of the rain came during the second half of the month as the normal seasonal trend towards wetter weather took hold again,” noted Chris Carss, a volunteer weather observer/recorder for Environment Canada at his Chemainus home.
“This year’s El Nino was too weak to last into December which saw a return to normal temperatures at the beginning of the month,” he added. “However, the trend towards above normal sunshine and little precipitation returned for the first week of December. It is expected that a more normal level of precipitation activity will return once again for the rest of December and continue into January.”
Near normal temperatures were expected to continue until an expected revival of El Nino along with milder but still unsettled weather before the beginning of February, Carss continued.
The mean maximum temperature for November in Chemainus was 10.5 degrees Celsius, well above the normal of 9.1C. The mean minimum of 5.8C was also considerably above the normal of 4.2C.
The extreme maximum temperature of 16.5C occurred on Nov. 2, with the extreme minimum of 1.0C on Nov 19.
The number of days with mostly or partly sunny conditions was 12 compared to the normal of seven. Of the 18 mostly cloudy days, precipitation occurred on all but one and the normal number of precipitation days is 19.
Total rainfall measured 186.6 mm, below the normal of 209.4 mm.
On Thetis Island, records kept by Keith Rush indicated November rainfall reached 163.1 mm., bringing the total for the year to 902.5 mm. November of 2017 had 237.7 mm and the average November on Thetis results in 177.1 mm.
In October, the rainfall total was just 80.8 mm, well below last year’s October total of 109.9 mm and the monthly average of 116.3 mm.
The highest October rainfall recorded by Rush was in 2016 at 281.4 mm and the lowest in 2013 of 11 mm.