One scientist is holding out hope for a sunny summer season after his findings reflected what many people already knew – that May was gloomy, wet and cold.
University of Victoria scientific assistant Ed Wiebe operates a network of weather stations around the Island. His UVic location recorded only two days in May which clearly exceeded the average daily temperature for that day, based on data collected over the last two decades.
“This was one of coldest Mays that we have recorded in the 20 years,” he said.
The cool and wet spring weather was expected with this year’s La Nina events – an interplay of wind and water processes in the Pacific Ocean that push the atmospheric jet stream up and bring rain-filled, cool winters for Vancouver Island. Wiebe said researchers have been surprised by La Nina conditions persisting longer than usual this year.
Pacific decadal oscillation, a longer-term climate-influencing occurrence, is in a negative phase currently, which usually contributes to cooler and wetter conditions for B.C. This teamed with La Nina could be responsible for the recent cool-weather patch, Wiebe said.
“We here in Victoria are very influenced by what goes on in the Pacific just next door.”
But there are some positives to a lack of sun, particularly over Vancouver Island and southwestern B.C.
“If you have a longer period with cloudy, cooler and wet conditions, then the forest fire risk is down – at least at the beginning of the fire season,” Wiebe said.
That’s because those blazes are influenced by the temperature, wind and precipitation around the time of ignition, with forest soils retaining rainwater being especially important to reduced fire risk, Wiebe said. Vigilance is still needed in case dry conditions in the near future elevate the risk.
Five years in the last 20 have seen more overall May rain recorded at Wiebe’s UVic station, but only 2002 topped last month in terms of the number of days where a measurable amount of rainfall was logged.
Greater Victoria is used to big, puffy cumulus clouds causing localized showers, but Wiebe said last month, being characterized by widespread overcast, made it feel darker than usual.
Those were likely caused by a host of atmospheric factors, including the La Nina and the jet stream impacts.
In his 30 years here, the arrival of consistent clear and sunny conditions in Victoria at some point has never let Wiebe down, though he noted that conditions like the ones seen this spring yield concerns about what some like to call ‘June-uary.’