People living in southern B.C. might find it an opportune time to head south of the border this weekend to fill up their gas tanks.

The Lower Mainland is seeing prices topping $1.33 per litre at some gas stations.

But in Washington, you can still fill up for anywhere from 94 cents to a $1.04 per litre.

A seasonal pattern is part of the reason for the price increases, according to Jason Toews, co-founder of the website GasBuddy.com.

"This time of year, we always see gas prices rising late February, early March," said Toews. "We always see prices rising in advance of summer driving season."

The growing instability in the Middle East is a big factor, too, said University of British Columbia business professor Ambarish Chandra.

"Libya is a small contributor to the world production of oil, but it is a contributor, so some of that is less oil in the world, so the price has to go up everywhere," said Chandra.

"We don't import oil from the Middle East, Libya in particular, but Canadian producers are going to pursue the same world price of oil they get in other countries and so the price in Canada will rise."

Gasoline hit $1.33 in some parts of Vancouver Friday. CBC

He said it's no surprise that gasoline is almost 40 cents per litre cheaper in Blaine, Wash., than it is in Burnaby, B.C.

"The States are just cheaper. They don't tax gasoline or most energy sources the way we do in Canada and in turn we don't tax at the same level [as] Europe."

With files from the CBC's Priya Ramu