To almost nobody's surprise, state Sen. Ray L. GarlandT (R-Roanoke) announced his candidacy yesterday for the congressional seat to be vacated at the end of next year by Rep. M. Caldwell Butler (R-Va.).

Garland told a news conference in Roanoke, the largest city in the nine-county 6th Congressional District, that he would be a stronger candidate than state Attorney General J. Marshall Coleman,another potential aspirant who was the losing Republican candidate for governor last month.

Although he said that Butler had not urged him to seek the GOP nomination for the seat, Garland -- generally considered a moderate-- linked himself closely to the outgoing incumbent.

"I can think of few major issues on which I would have voted differently from Butler in Congress," Garland said. "We are cut from the same cloth, which might best be described as copper-bottomed, hard money, Main Street Republicanism."

Garland, 47, was first elected to the state General Assembly in 1968. Two years later, as the Republican candidate for the U.S. Senate, he came in a distant third behind independent incumbent Harry F. Byrd Jr. and Democrat George Rawlings. He is a businessman and former college teacher.

No Democrat has announced for the seat. One prospect often mentioned is state Del. Richard Cranwell of Roanoke County.

A less orthodox candidacy for another political post -- mayor of the District of Columbia -- was announced yesterday by the Rev. Harry W. Lanier Jr. He made his announcement at a news conference in the maximum-security facility of the city's LortonReformatory, where he is serving an 8-to-24-year term for assault with intent to commit robbery.

Within the prison's high brick wall, the 32-year-old Lanier read a three-page statement in which he argued that his life as a Washington youth who went wrong and now considers himself rehabilitated would qualify him for the post.

"I do not want to be mayor just for the title," he said, "but to propose new policies, programs, workshops, projects and jobs that will close the gaps" among all segments of the population.

An inveterate letter-writer, Lanier said that his correspondence once brought greetings from Britain's Queen Elizabeth II and invitations to President Reagan's inaugural ball and D.C. Police Chief Maurice T. Turner's swearing-in ceremony. He said he reluctantly declined the invitations.

Lanier, whose ministerial ordination came by mail from the American Fellowship in California, said he had telephoned the D.C. Board of Elections and Ethics and been told that there was no barrier to his candidacy. But William H. Lewis, the board's general counsel, said yesterday this isn't so -- that only qualified D.C. voters can run, and convicted felons such as Lanier cannot vote while serving time.

Metropolitan Washington has been spared a heavy snowfall, but not so the mountains of western Maryland. From the Garrett County hamlet of McHenry came word yesterday that the accumulation was 18 inches, with traffic permitted only on some roads.

But the weather pattern was peculiar. "One minute it's snowing so hard you can't see," said state trooper Bill Rice, "and the next minute the sun is shining."

Under pressure from state Sen. Adelard L. Brault (D-Fairfax), Virginia highway officials are expected to resume negotiations with Fairfax County over the alignment of the proposed cross-county highway called the Springfield Bypass.

County officials had asked that the issue be reopened after the resignation of highway commission member William B. Wrench, whose property ownership along the state-backed route was disclosed only after he voted for it and against the county-supported alignment. State highway chief Harold King later told the county that the issue was settled.

After Brault interceded, King said, he instructed his planning director to meet with his counterparts in Fairfax. But King made it clear that any change in the state's position is unlikely.

Forty-eight years behind most of the nation, and 13 years behind most of Virginia, liquor by the drink became legal Thursday in Danville, a manufacturing city of 46,000 a few miles from the North Carolina border.

In a referendum on Nov. 3, fully 59 percent of the voters approved of the city going wet, as they used to say in Prohibition days. Jesse Weaver, a local businessman, bought the first drink in the Tobacco Exchange restaurant. Swizzling his Scotch and water, Weaver exulted: "Danville's come alive."