Gas prices shot up by 8.5 cents per litre in Winnipeg, driven by problems at refineries in the United States.

But the spike might not last too long, experts say.

Dan McTeague, founder of Tomorrow's Gas Price Today, which scrutinizes gas prices across the country, expects the price to start dropping off and possibly level out at 121.9 by Sunday.

He said the problems at the refineries started last week. The supply of gas to retailers was reduced due to maintenance and at least one shutdown.

As a result, the price to retailers went up.

McTeague said they've been paying about 115.0 per litre for their wholesale cost, which didn't give them much profit margin when the pump price was 118.4 and the government tax still had to be deducted.

And when people pay with a credit card, retailers face a further charge. In the end, many were losing money per litre, McTeague said.

To compensate, prices have shot up from Kelowna, B.C., to Winnipeg.

In most jurisdictions, prices will go up for a day or two and then drop, but Winnipeg is different, McTeague said.

"Winnipeg's a bit of an odd market in the sense when it goes up it holds for about four to five days and then it drops and it will stay there for about a week or two, and then it'll drop again or go whatever direction the market is," he said.

If it's any consolation, one year ago Winnipeggers were paying 128.9 per litre.