(CNN) -- If you're planning on traveling over the Fourth of July to the East Coast, watch out for Arthur.
The first named tropical storm of the season may make driving hazardous on Wednesday and Thursday but should not spoil most of Friday's festivities, as it veers away from land.
Arthur looks like it will spare the colossal fireworks show on Washington's National Mall, weather forecasters say, whisking out of range.
The storm is expected to morph into a Category 1 hurricane on Thursday, farther south off the coast of North Carolina, with top wind speeds of 75 mph.
But it is predicted to track off to the east in time for Washington's show.
If predictions turn out to be off, the nation could get live television coverage of the season's first hurricane.
PBS is planning to broadcast the pyrotechnics blossoming over the Reflecting Pool live via 20 cameras.
Storm clouds on Arthur's coattails might throw rain on the Independence Day parade around noon on Friday. There's a 30% chance, the National Weather Service said.
But after sundown, the skies should be mostly clear and cool. Much of the East Coast should share in the good conditions late Friday.
Those wet roads
Boston might become the unlucky exception.
Arthur is predicted to fling thunderstorms over the fireworks show there late Friday. State officials aren't ready yet to commit to -- nor to cancel -- the show.
"I think we're going to defer any conversations or decisions about the weather at least until tomorrow," Massachusetts State Police spokesman Timothy Alben told CNN affiliate WCVB on Tuesday.
Arthur could trigger the wrong kinds of bangs and booms on the roads leading up to the 4th. It is the busiest week of summer travel, according to AAA.
Most of those travelers will be going by car, right around the time Eastern U.S. roads will get soaked.
"They are potentially staring down the barrel of a loaded gun," said AAA spokeswoman Yolanda Cade.
People traveling to North Carolina's Outer Banks, a string of barrier islands, should be careful, CNN meteorologist Chad Myers said.
It's hard to get onto and off them in a car. The islands are low, and rain could easily wash onto the roads, making them impassable even before the eye of the storm makes landfall, he said.
In addition, the weather service predicts high winds there on Thursday.
Still a tropical storm early Wednesday, Arthur was slowly creeping up Florida's northern Atlantic coast, dumping rain there and over the Bahamas, the weather service said.
With maximum sustained winds of 60 mph, it was approaching hurricane strength.
The same Florida coast might be an ideal place to spend July 4th, as Arthur should be far away from there by Friday, and fireworks will burst over the beaches from Key West to Jacksonville.
By late Saturday, Arthur will be gone from the U.S. coast, providing for mostly pleasant weekend weather from Florida to Maine.