Low gas prices are something for drivers to celebrate this July 4th, with costs at the pump expected to hit their lowest levels since 2021. 

The average price of gasoline on Independence Day is expected to be $3.49 per gallon nationwide, the lowest price it's been on the busy travel holiday in three years, according to GasBuddy, a fuel savings platform. 

That could mean serious cost savings compared with a few years ago for the 60.6 million motorists who are expected to travel by car to celebrate the federal holiday, according to AAA.

Last year, this national average price of gas was $3.50, just a penny higher than this year's projected price. In 2022, the average cost of gas was more than $1.30 higher than it's expected to be this year, driven up at the time by Russia's invasion of Ukraine in February which caused oil prices to spike. 

Where gas is cheapest

Gas prices have ticked upward slightly since the beginning of June, when they fell to as low as $3.39 per gallon.

Still, in some states fuel costs are significantly lower than the current national average. In Washington, average gas prices are down 71 cents a gallon compared with one year ago. 

"For those hitting the road to celebrate Independence Day, gas prices have seen modest recent fluctuations, but most states are seeing prices near or even well below where they were a year ago," Patrick De Haan, head of petroleum analysis at GasBuddy, said in a statement. 

But De Haan warned that hurricanes and other tropical weather events could disrupt refineries and cause prices at the pump to spike later in the summer. 

"While the first half of the summer has been relatively smooth sailing, the road ahead may be bumpy. Activity in the tropics has increased, and projections remain for a very busy hurricane season. Even after the holiday fireworks are over, we'll be watching for any potential fireworks at the pump that could be brought on by hurricanes disrupting refineries," he said. 

How to save on fuel costs

For motorists looking to save money on upcoming road trips, there are ways to minimize gas usage while driving. 

• Accelerating hard wastes fuel, while accelerating gently saves gas. Toyota offers this tip: "Aim to take about five seconds to accelerate your vehicle up to 15 miles per hour from a stop," the automaker said. 
• Sudden changes in speed can increase gas consumption by up to 30% on the highway, so aim to drive at a steady pace, Toyota added.
• Progressive, the insurance company, adds that newer cars tend to be more fuel efficient than older models. A quick tuneup to clear your vehicle's clogged air filters will also enable more efficient fuel consumption, and potentially help you save on gas costs.
• Check your tire pressure, as underinflated tires can lower your fuel efficiency. 

Megan Cerullo

Megan Cerullo is a New York-based reporter for CBS MoneyWatch covering small business, workplace, health care, consumer spending and personal finance topics. She regularly appears on CBS News 24/7 to discuss her reporting.