More than a quarter century has passed since a major hurricane — Hugo — hit South Carolina’s coast.

But just two weeks have passed since tri-county residents got a reminder of how quickly our already-crowded roadways can become thoroughly jammed. On May 26, an accident that caused a large spill of diesel fuel from a tanker truck forced the Arthur Ravenel Jr. Bridge’s northbound lanes to be closed for nearly nine hours and the southbound lanes to be closed for nearly eight.

That produced a revealing ripple effect of severe traffic snarls throughout the community.

And remarkable population growth along our state’s coast over the last few decades has produced a severe challenge for when — not if — the next mass evacuation from an approaching hurricane is required.

So don’t take too much consolation from the recent federal forecast of a relatively mild hurricane season.

Sure, the National Oceanic and Atmospheric Administration predicted just six to 11 named storms, with only three to six developing into hurricanes and no more than two reaching “major” (Category 3 or higher) status. But as recent history shows, expert projections of storm numbers and strengths are often inaccurate.

And even if there’s only one major storm this year, if it heads here, moving people safely away in a timely manner will be a major test.

It’s reassuring to know that government officials at all levels have made sweeping improvements in evacuation plans since the Hurricane Floyd debacle in 1999. As that powerful storm advanced toward what looked like a certain direct hit on our state, colossal gridlock ensued on roads, particularly I-26, heading inland.

Floyd then fortunately (for us, not for North Carolina coastal residents) took a sharp turn north. But the Floyd traffic nightmare in our state highlighted the need to facilitate inland traffic flow by reversing lanes that usually go toward, not away from, the coast. Official agencies also have worked to coordinate other evacuation efforts in a much more effective manner.

Still, remember that Charleston, Hilton Head Island and Myrtle Beach have been among the fastest-growing metro areas in the nation over the last few years.

And when Floyd gave us a big scare and a presumably lingering lesson 16 years ago, the population of the tri-county (Berkeley, Charleston and Dorchester) was roughly 500,000. Today it’s more than 720,000.

Meanwhile, though there has been plenty of road construction around here since 1999, not much of it has created more routes to carry people out of hurricane harm’s way. Indeed, our General Assembly again neglected pressing road needs throughout the state in this year’s session by failing to enact a hike in the state gas tax, which was last raised two years before Hugo.

So remember that preseason hurricane forecasts are understandably unreliable.

If you have a storm plan, review it. If you don’t have a storm plan, make one.

And plan on a timely departure when — again, not if — a major storm warrants a major evacuation from the South Carolina coast.