RACQ spokeswoman Renee Smith said the low point of the fuel cycle was expected this week, but then prices were predicted to increase to almost $1.50 "in the blink of an eye".

Monday signalled day 33 of the petrol price cycle, with Ms Smith saying the days of "cheap Tuesday", when motorists knew the fuel prices would be low, were long gone.

The average at Brisbane bowsers on Monday was $1.35, but some service stations were selling fuel for $1.31 per litre.

"While prices around $1.30 per litre may not seem cheap to motorists, some might remember when prices were close to one dollar last year, due to wholesale prices at the moment once a service station drops below $1.30 we will be considering that as cheap," Ms Smith said.

Service stations north of Brisbane in the Moreton Bay region were selling fuel for about $1.25 per litre, but these prices were not expected to last for long.

Ms Smith said the low and peak of the fuel cycle could happen in the same week, but when the prices do go up, either this week or next, it will be a 20?? jump without warning.

"Prices will go up sharply and are likely to go into the high $1.40s but we don't expect them to hit $1.50 per litre," Ms Smith said.

"At the last peak, prices were just over $1.49 per litre, but we hope it will be a few cents per litre cheaper this time.

"When cycles do turn and go into the peak, it is without warning and catches motorists by surprise, so drivers need to fill up this week in south-east Queensland because prices can go up in the blink of an eye."

According to fuel price comparison app MotorMouth, the cheapest unleaded fuel near the greater Brisbane area on Monday could be found at Puma in Narangba (122.7?? per litre), 7 Eleven at North Lakes (123.2?? per litre) and Caltex in Burpengary (123.7?? per litre).