The Memorial Day weekend marks the traditional beginning of the summer travel season, and we’re back with our annual guide of problematic routes and roadways you might want to avoid in your rush to get out of the Washington region. The 95 Express Lanes project is on a fast track, but that probably means summer vacationers won’t be going anywhere fast when they drive through that construction zone on Interstate 95 in Northern Virginia. Of all the compass points travelers will follow on their getaways from the D.C. area in 2014, the most difficult — for the second summer in a row — will be due south. The express lanes project, begun in late summer 2012, is building “29 miles in 29 months,” said Walter J. Lewis III, project director for Fluor-Lane 95, the construction company. The 2013 work included construction of nine bridges, sometimes forcing weekend detours on I-95. Through the rest of this year, the remaining work will include frequent weekend shutdowns of the HOV lanes in the middle of the interstate, limiting its capacity to handle vacation traffic. While that slow ride is likely to be the biggest challenge at the beginning and end of long trips, it won’t be the only one. Here’s a look at what’s ahead along the main summer escape routes.