Chilliwack – November 2020 Weather in review. Data recorded by Roger Pannett, Volunteer Weather Observer for Environment Canada at City of Chilliwack.
|Variable||November 2020||30 Year Average|
|Mean Maximum||9.61 C||9.3 C|
|Mean Minimum||4.08 C||2.9 C|
|Mean Temperature||6.84 C||6.1 C|
|Rainfall||234.4 mm||228.8 mm|
|Snowfall||3.0 cm||10.2 cm|
|Total Precipitation||237.4 mm||239.0 mm|
|Days of Rain||21 days||18 days|
|Days of Snow||1 day||1 day|
|Total Days of Precipitation||21 days||19 days|
|Relative humidity average||77.84 %||.|
After a mild and sunny start to November a rapidly intensifying Pacific frontal system, carrying sub-tropical moisture, produced heavy rain and warm gusty winds. On November 4th, temperatures peaked at 18.9 ⁰C, 7.9 ⁰C above normal, the warmest since the 19.6 ⁰C on November 6th, 2014.
As a ridge of high pressure built over northern B.C., on November 7th modified arctic air arrived in the Fraser Valley. With the fresh and gusty north-east winds, the relative humidity decreased to 21%. On November 9th temperatures dipped to the low temperature for the month at -0.5 ⁰C with some wet snow the following evening.
By mid-month typical wet and mild November weather conditions returned. However, during the evening of the 13th, an unstable and turbulent air mass triggered a rare November thunderstorm plus hail and heavy snowfalls on the high passes. Mild and generally rainy conditions continued to months end with strong and gusty south west winds at times.
It was the 13th consecutive month and 5th consecutive November with above normal mean temperatures.
Total precipitation was close to normal.
The City of Chilliwack year to date precipitation totals are 1,392. 5 mm on 175 days compared to the 30-year average of 1,585.7 mm on 152 days.
It has been reported, ‘La Nina,’ has developed. Consequently, a cold and stormy winter is expected with above normal snow fall in southern B.C., including the Lower Mainland and Vancouver Island.