September brought heat, poor air quality and little rain for Chilliwack

Last month was the warmest September in 125 years in Chilliwack.

With mean temperatures at 18.46 degrees Celsius, 2.86 degrees C above normal, it was the warmest September since Chilliwack temperature records commenced in 1895, wrote Roger Pannett, volunteer weather observer for Environment Canada in his September weather report.

It was also the fifth consecutive September with above normal temperatures.

“On Labour Day (Monday, Sept. 7), with an amplified ridge of high pressure over northern B.C, rising atmospheric pressures produced strong and gusty, dry outflow winds,” Pannett said.

That day, temperatures rose to 28 degrees C (6.8 degrees C above normal) with a very low 12 per cent relative humidity.

Sept. 9 proved to be the hottest day of the month where temperatures reached a high of 32.9 degrees C (11.2 degrees C above normal). That day broke the previous record of 32.2 degrees C in 1963.

“As the ridge of high pressure shifted eastwards with a consequent southerly air flow, for over a week, very smoky conditions developed coming from the devastating Oregon and Washington state wildfires,” he said. “Air quality readings deteriorated to 10+, a very high health risk and lasting longer than the September 2017 wildfire smoke situation.”

READ MORE: U.S. wildfires putting Lower Mainland air quality among the worst in the world

With higher temperatures came a lower amount of rain, too.

The total precipitation for September was 78.5 mm, which was 34.2 mm less than the 30-year average of 112.7 mm. Rain fell on only nine days throughout September, compared to the average 11 days.

The previous warmest September was in 2017 with a mean temperature of 18.32 degrees C.