Hang onto your wallet.

Prices at the pump have gone up 8 cents a gallon over the past week in the Garden State, from $2.51 to $2.59 on average, and they’re expected to keep climbing for at least the next couple of months.

Robert Sinclair Jr., manager of media relations for AAA Northeast, said this is part of the normal rise and fall of gas prices, and right now “we are in the rise part of the cycle" — as the weather warms up, more people get on the road and demand rises.

“Also we’re seeing now the switchover to what’s called low-vapor-pressure gasoline, also known as reformulated gasoline or simply summer gasoline," he said.

He said this warmer-weather gas is designed to lower the amount of ozone that that’s created from the emissions of your vehicle, “so the formula is switched to a lower vapor pressure. That also helps to reduce the evaporation of the gasoline out of your tank, especially when you’re filling up.”

He said those blends are more complicated to refine, and they’re more difficult to distribute — and that leads to the price going up.

Sinclair said the price of crude oil has also been rising, up about $10 over the past month or so, and that is also helping to push gasoline prices higher.

He said prices are expected to continue to rise until at least the end of May, and perhaps till the Fourth of July, going up another 10 to 20 cents — but after that they will slowly start to drop.

“That could or could not happen depending on various things — the availability of crude oil, any political unrest that might be happening in major oil-producing parts of the world," he said.

He added even though gas is getting more expensive, “drivers should realize in New Jersey you still have the cheapest gas in the region.”

A new AAA survey finds New Jersey prices are on average 2 cents a gallon cheaper than gas prices in Connecticut, 7 cents cheaper than New York, and 16 cents cheaper than Pennsylvania.

South Carolina, Mississippi, Arkansas and Alabama have the cheapest gas per gallon, an average of $2.30, while gas in Hawaii is most expensive at $3.35 a gallon.