Summer is less than one month away, but winter isn't releasing its grip on the summit of the Coquihalla connector between Merritt and Kelowna.

A weather advisory has been issued for the route, warning up to four centimetres of snow could fall before changing to showers this afternoon.

There's concern because most drivers have already removed their winter tires and may be unprepared for the unexpected snowfall.

Meanwhile, Environment Canada says as much as 20 centimetres of snow could fall in the Muncho Lake area of northeastern B.C., west of Fort Nelson, while heavy rain could deluge the remainder of that region until at least tomorrow.