At the start of September, with a strong ridge of high pressure lingering from the month before, dry, sunny and hot conditions prevailed in Chilliwack.
There were four hot days with temperatures above 30C, which surpasses the historic average of only three, according to Roger Pannett, Chilliwack's volunteer weather observer for Environment Climate Change Canada.
It's been a warm summer. Since May, there were a total of 31 sweat-inducing days, with temperatures of more than 30C, were only exceeded by the 34 hot days recorded in 2018.
Over 30 years from 1951 to 1980 the "hot day average total" was seven days, with a +5-day standard deviation.
On Sept. 5 temperatures peaked at 33.5C (+11.9°C above normal) with a low 24 per cent relative humidity.
"It was the hottest September day in seven years," Pannett said.
On Sept. 30, beneath clear overnight skies, the minimum temperature for the month was 4.7C the coolest September night in 12 years.
After Sept. 7 temperatures cooled. However night and day temperatures remained above normal.
The mean temperature for September was 17.58C, 1.98C above the 1951 to 1980 average with a plus or minus 1.3C standard deviation. It was the ninth consecutive September with above-average mean temperatures, a trend never previously observed since Chilliwack temperature records commenced in 1895.
September was also the seventeenth consecutive month with above average temperatures, including 13 months with mean temperatures 1.3C to 4.74C above average.
The passage of a weak Pacific frontal system, with light rain on Sept.11, ended the third drought of the summer which had lasted 14 days.
Typical September unsettled conditions persisted to month's end with nine days of rainfall, but only amounting to 57.6 mm, 48.9 per cent below normal. It was the third consecutive September with below-normal rainfall. The overall drought conditions of the past 27 months continues, with only June and August recording above normal precipitation.
The City of Chilliwack 2024 precipitation total to date is 907.8 mm on 122 days compared to the 30-year average of 1,160.5 mm on 117 days.
Three high temperature records were observed:
Sept. 1, High mean 23.6C (+6.7C) 22.95C in 2022,
Sept. 6, High mean 24.5C (+9.0C) 23.5C in 2014,
Sept. 9, High min 15.8C (+5.9C) 15.6C in 1958.
