Travel in B.C.'s Okanagan-Shuswap region has been slowed by a heavy snowfall, with about 15 centimetres blanketing the areas Wednesday morning.

The B.C. Ministry of Transportation said the heavy snow has now moved into the Kootenays, making driving tricky across much of the Southern Interior. However, there have been no road closures.

Snow covers a highway near Castlegar, B.C.
(CBC)

Some flights at the Penticton airport have been cancelled, and a few flights in Kelowna have been delayed. 

A snowfall warning is in effect for the Okanagan and much of southeastern B.C., with another 10 centimetres of snow expected in the Kootenays by late Wednesday.

Check rental cars for snow tires, RCMP warn

Meanwhile, the RCMP have warned people who rent cars in Greater Vancouver with plans to drive to the Interior or Whistler to check their tires.

The law requires proper winter tires or snow chains on many mountain passes, but a survey by CBC News found that it's nearly impossible to find a rental car with either safety feature.

None of the more than a dozen rental car agencies in Vancouver contacted by the CBC offered snow tires or chains.

Dale Finch of the Automobile Retailers Association, which speaks for most  rental car companies in the province, said renters planning to drive into the Interior should rent trucks or SUVs, which are equipped with all-season radials.

But the Canada Safety Council and the RCMP warned they may not be suitable in heavy snow.