When people wake up in the Okanagan on Saturday morning, the weather is expected to be vastly different than it was 24 hours ago.
This is a springtime trend most common in BC – unpredictability.
This weekend, however, the seasonal flurry is coming straight for the Okanagan.
“What we’re going to see is a transition from a winter season to a summer season, which is going to bring in unstable air masses and that leads to springtime convection,” said Derek Lee, a meteorologist at Environment and Climate Change Canada.
“This is the volatile weather we should expect to see … a sunny morning, a quick change to a very cloudy afternoon and then it can get very cold.”
Temperatures in the Okanagan are expected to drop into the single digits on Saturday and Sunday, as people in the region were treated to a week high of 15 degrees Celsius to 17 degrees Celsius.
However, there is no chance of rain and thundershowers in the Okanagan’s forecast for the weekend.
With spring convection, however, this can change quickly.
“This weekend is a great example of that,” Lee explained.
“We’re quickly going from warm to cold temperatures, which comes with unstable air masses that are quite unpredictable.”
Meteorologists associate convection with the hail and thunderstorms that typically occur in summer.
Spring convection may be weaker than in summer, but that doesn’t change the level of unpredictability that people can expect to experience in April and May.
“Volatile air masses don’t happen every day, but they do occur from time to time during the season,” Lee said. “I would say it’s the typical BC weather pattern … it’s very unstable because of the imbalance in the atmosphere when we get to spring.
“When you get cold air on top of warm air, it creates instability.”
Environment Canada previously predicted springtime in the Okanagan to be “colder than usual”.
The arrival of spring convection and its erratic shift in temperatures below 10 °C, will only support the claim when the season reaches the mid-April point.
“We’re going to sandwich a few cold days in between our normal days and it looks like that trend is starting to take shape,” Lee said.
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