It ain’t for nothing that they say it sounds like thunder. Throw open a window to catch the night's gentle spring air and you’re likely to hear the rumble of motorcycles passing in the distance.

After a harsh winter, the fleeting weeks of spring have beckoned cyclists to exult the season. This weekend their engines will echo from the beach resorts to the winding roads of the Blue Ridge Mountains, but nowhere will they roar in unison like they will in the nation’s capital as the annual Rolling Thunder gathering draws hundreds of thousands of riders.

Last year an Indiana rider died in a collision near the Mall after a Rolling Thunder event, and four out-of-state riders who were coming to observe it were hospitalized after they collided on Interstate 66 in Vienna.

For some motorcyclists closer to home, the inviting spring weather has proved deadly. At least a dozen riders have died in Maryland and Virginia this year.

“It’s not surprising that there have been some local motorcyclist deaths recently,” said Jonathan Adkins, executive director of the Governors Highway Safety Association (GHSA). “The last couple of months have provided nice weather after a long, horrible winter, so many folks were no doubt anxious to get out and start riding again. This continues to be a very dangerous way to travel, and we need to rethink how we address the issue.”

There is good news in that motorcycle deaths seem to be declining significantly in the District, Maryland and Virginia, according to a GHSA tally from 2013. But, experts say, a troubling fact remains: Too many motorcycle riders who crash are drunk or speeding.

“In 2012, almost half of all fatal motorcycle crashes did not involve another vehicle — likely a motorcyclist speeding and or impaired,” Adkins said. “ ‘Share the road’ messages would not have had an impact here.”

Based on preliminary data from state safety offices, Adkins projected that motorcycle crash deaths dropped by 7 percent in 2013, on par with the number who died in 2011.

That year, 4,612 motorcyclists died, 1,397 of them were legally drunk and 1,702 were not wearing helmets. The National Highway Traffic Safety Administration estimated that 706 would have survived had they worn helmets.

In 1976, when Congress relaxed pressure on states to require helmets, all but three mandated their use by all riders. Since then, 31 states have repealed their laws. Maryland, Virginia and the District still require them.

The decline between 2012 and 2013 was particularly pronounced in Virginia and Maryland, which the GHSA attributes to a cold, wet spring in 2013 that kept some riders off the roads.

There was a 22 percent drop in Maryland deaths in 2013, and a 15 percent drop in Virginia. The District had one fewer, three deaths rather than four.

If the trend set in recent weeks continues, there may be an increase in deaths during this warmer, drier spring. Five of the 2014 deaths — including the latest in Oxon Hill on Friday — have occurred in Prince George’s County.

Michael Marquis, 32, was killed April 6 when his cycle collided with a vehicle emerging from a parking lot on Indian Head Highway.

Jose Roberto Gomez, 35, died seven days later on Interstate 95 when his motorcycle collided with a car and he was thrown in the path of a tractor-trailer rig.

Garrett Greene, 24, died May 8 when his motorcycle collided with a car near Central Avenue and Enterprise Road. He was pinned under the overturned car.

Three days later, a motorcyclist whose name has not been released by Maryland State Police plunged to his death from a ramp on U.S. Route 50

“The most troubling part of this is that the hotbed of these accidents is in Prince George’s County,” said John B. Townsend II of AAA. “Prince George’s has many of those long, straight roads — Indian Head Highway, Route 50 and I-95 — that encourage people to do adventurous things that get them killed.”

Townsend said an unusually high number of the region’s 2014 motorcycle fatalities have involved collisions with other vehicles.

“The response of many drivers is simply to say, ‘I didn’t see the rider’,” he said. “How can you be in traffic with a motorcycle and not hear it? Too many people are distracted.”

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