Memorial Day and the summer travel season are fast approaching, which means gas prices are on the rise again. People who were happy to see $2 gas earlier this year are now greeted by a national average of $2.27 for a gallon of regular. The price of gas has climbed 16 cents in just a week, 22 cents in a month. The increase is most likely tied to the rising price of oil in recent weeks. There's also the annual switch over to a higher blend of ethanol for warm weather months. The good news is the average price of diesel fuel hasn’t risen as sharply as gas prices. The national average for a gallon of diesel is $2.28, up only 3 cents from a week ago and 1 cent higher than a month ago. Modern diesel cars like the VW Jetta TDI get roughly 30% better gas mileage than their standard gasoline counterparts. And to make everybody feel better, analysts do not expect a repeat of last year's $4 gas prices when we hit an all-time high on July 17,2008 for both regular unleaded — $4.11 — and diesel — $4.84.AAA Daily Fuel Gauge Report