CHICAGO (CBS) – The party is over at the gas pumps, prices across Chicago are on the move up.

It is time for the summer blend prices, but just what does that mean? CBS 2’s Marissa Bailey went out to find answers.

READ MORE: Chicago Public Schools High School Students Return To Classrooms

It may not even be March yet, but summer-blend gas prices are here. The area has reached the beginning of the end of the cheap gas price season.

“This is kind of the trajectory where gas prices will start to trend higher.”

Patrick DeHaan with said the switch to summer blend started this week and we could see prices go up as much as 20 cents almost immediately.

READ MORE: 'Optimistic For His Continued Recovery:' Doctors On Toddler Kayden Swann After He Was Shot On Lake Shore Drive

“By later tonight, you will notice if you are coming home to the suburbs that gas prices shot up, so in many cases if you can ship around, fill the tank sooner, I’d certainly recommend it.”

DeHaan said city gas prices tend to fluctuate more slowly, but no matter where you live or buy gas this is the start of an expensive few months for gas.

“Every one to two weeks, you’ll see an increase at the pump,” DeHaan said.

“I wish it would wait until at least April or May when it is at least nice outside, but it’s gas prices,” said Rachel Durbin, Chicago.

MORE NEWS: A Violent Trend: Increasing Numbers Of Children Killed By Gun Violence In Chicago

DeHaan said if you want to save some money when you buy gas, try to buy it at the beginning of the week. That is when prices do tend to be a little lower.