Mark MadrygaDon’t pack away those winter sweaters just yet. Although spring is almost here, temperatures aren’t guaranteed to rise quickly, says meteorologist Mark Madryga. “Warming is fairly slow, due in part to mountain snowpack and persistent cool ocean water at this time of year. It takes some time for that to turn into spring mode.”

That’s why you might still see higher heating bills. In autumn, temperatures drop off more quickly, which explains a faster rise in heating costs in the fall versus the slower drop-off in heating costs transitioning into spring. Even in Vancouver, the average temperature drop-off between October and December is 6.7 degrees, but a rise of only 4.5 degrees between February and April. A few days of colder Arctic air can generate sub-freezing nighttime temperatures and—even in April—snow. The same rings true for the Okanagan where average lows in April are a chilly three degrees.

This winter we’ve experienced a strong El Niño with a number of places recording temperatures on the high side of historical averages—but a balmy spring is still hit or miss. “The effects of El Niño are strongest typically in winter for western North America,” says Madryga. “Temperatures that may be a little warmer during the late winter will not necessarily persist into spring. It can go either way, which can definitely factor into a slower drop-off in heating costs.”