There are roadside signs in Northern Virginia, scrawled in paint on plain boards, advertising for plumbers and bricklayers.

Far across the metropolitan area to the northwest, at the several branches of Chevy Chase Savings & Loan in the Maryland suburbs, there are long lines of consumers waiting to put down minimum deposits of $500 in exchange for new pocket calculators, being given out as premiums. The list of new accounts or additions to older accounts on the desk is staggering, showing new savings of $700, $1,000, $3,500 and more.

Last Saturday night at the Landmark shopping center in Alexandria, however, business at the big Woodward and Lothrop, Hecht and Sears, Roebuck & Co. stores was anything but brisk. Clerks talked to each other as obviously cautious consumers weren't anxious to spend big bucks in the wake of an apparent last-minute buying binge before Christman.

The major sales came before the holiday, fattening retailers' revenues for the month of December but undoutedly cutting into profits as merchandise moved only with discount pricing.At some stores, there is an overstock of goods now -- especially clothing -- and it's a buyers' market. In a truly extraordinary situation, buyers have found that they could bargain even with a department store clerk on how much they would pay for a handbag, for example.

In Annapolis, Gov.-Elect Harry Hoghes is preparing to take office at a time when his state's economy has regained strength and there is talk of cutting taxes. New D.C. Mayor Marion Barry already has taken over this central city's government and among his first actions was a call for cooperation of business and labor in solving the federal city's problems -- chief among them, jobs for black youths, better public school education and economic development.

The black-white contrast of poverty and wealth here has prompted the new mayor to describe high unemployment "an economic disaster."

Virginia Gov. John Dalton, meanwhile, is hoping that cautious revenue forecasts will keep state activities ongoing without the need for higher taxes, even if there is a mild recession. And his state continues to be among the most successful in attracting new business, jobs and tax revenues.

Over on Maryland's Eastern Shore, leading chicken producer Frank Perdue is expecting another good year, although he warns of "boom and bust" cycles in his business. Competitor Frank Haper, of Showell Farms, doesn't want to talk about an economic downturn. "Let's not talk our way into a depression," he says.

And, to the south in Tidewater Virginia, the taverns and discotheques in Norfolk are packed while available houses and apartments disappear as fast as they can be built, in a superheated economic environment fueled by the world's largest U.S. Navy installation and a busy port.

These brief sketches help explain what should be said about the Washington region's economy in 1979: There will be no recession locally, but ther relatively affluent consumers who populate large parts of this city and its suburbs as well as major metropolitan areas in Maryland and Virginia are going to save what they can (with the highest interest rates possible) and spend a little less on goods they don't have to purchase, in an attempt to cut back on the receord levels of consumer debt they now owe to credit card firms and retailers.

For the nation as a whole, many Washington business leaders expect a mild recession. But the strength of construction activity here, in particular, leads most business leaders to plan for another year of modest growth in the regional economy. And big government is not disappearing despite Jimmy Carter's rhetoric, which convinces area business people to plan for continued gradual population growth at least into the mid-1980s, in a market where families have more spendable income than anywhere else.

Moreover, there is a new era of hope about the District of Columbia's economy. Despite the suburban expansion of the last three decades, expanding industrial parks, new businesses and sprawling malls that attract shoppers around the Capital Beltway, the city remains the major emplyment magnet in the region, the cultural centerpiece and the biggest retail marketplace.

But D.C.'s economy was stagnant for a full decade until a downtown construction boom and a much-heralded return to the city by some professionals and young people started in the past two years. Now, with what generally is regarded as a more aggressive city government and with congressional approval for a convention center, hopes never have been higher.

A heady atmoshpere has been brewed by such developments as the start of major redevlopment along Pennsylvania Avenue, the first significant post-World War II construction east of 15th Street and dozens of new hotel, office and residential complexes.

It adds up to nothing but enthusiasm about the local economy for the near term. As Vincent Burke Jr., chairman of Riggs National Bank, says, for the nation as a whole, 1979 is "full of question marks." The dollar must become stronger once again and lower interest rates must return "if the general economy is to enjoy better times," Burke advises. "But I'm bullish on the D.C. area. If it's not depression-proof, it's certainly the last (region) that would be affected."

Edward Toohey, vice president of Merrill Lynch, Pierce, Fenner & Smith, agrees that "despite the prospect of a modest recession on a national basis, we see nothing more serious than a slowdown in the growth rate of the Washington metropolitan area."

To William Fitzgerald, president of Independence Federal S&L, "For 1979 I see a big muddled picture, a lot of if's more than anything. We're fortunate that the economy in this area is stable because of the federal government, but no one is isolated from what's happening to the dollar."

The dollar woes and high interest rates will have an impact, but not necessarily all bad. For example, Mack Co. Chariman Meyer Gelfand says that if a national recession occurs in mid-1979, there will probably be some reduction in industrial employment but no "significant impact" on profits for his big food services and vending firm, based in Cheverley. It "may prove beneficial in the long run by slowing the rate of inflation," he says, backing up exhortations last week by Federal Reserve Board Chairman G. William Miller.

Speaking to a Washington Post business outlook luncheon, Miller told area business and government leaders that continued austerity is necessary to fight inflation over many years to come.

Although Miller said government leaders must not be fearful slower economic growth, he said he sees no recession in 1979. The only major economic sectors where the Washington regional economy may be soft in 1979, compared with the past two years of substantial growth, are expected to be retailing and the housing portion of overall construction.

That means fewer employment opportunities for less skilled workers in building trades and fewer part-time jobs at stores, developments that should contribute to gradual increases in area unemployment this year and a continuing, very serious problem for new Mayor Barry in the Distrist -- finding jobs for black youths, more than 40 percent fo whom have not been able to get work in recent years.

"Although it will be a very difficult year, I believe this area will do better than others," said Woodies chairman Edwin Hoffman. "Our home store will do the worst because of problems with the high interest rates and associated housing fall-off... although we'll hire fewer part-time people than in more active periods, we plan no lay-offs of our regular staff."

Hecht's president Allan Bloostein, whose firm provides the stiffest department store volume competition to Woodies here, forecasts "continued growth for us in what we believe to be one of America's strongest markets. We think our recently opened store at Lakeforest in Gaithersburg and the two new big store additions, one in Annapolis and the other, Security Mall in Baltimore County, will contribute substantially to this growth."

Sums up the Virginia Department of Labor and Industry: "In light of recessionary predictions from many sources, it will be crucial to not if, once Christmas shopping is completed, consumers can retain their spending momentum evidenced since the 1975 recession. If so, recessionary prognostications may prove ill-founded. However, it may be that the shopper has already purchased expensive hardgoods in anticipation of continued high inflation. Luxury and chic items (sold well) this Christmas season as many shoppers are splurging and disdaining or postponing the purchase of traditional necessities."

In the housing area, one development recently already is breeding some short-term pessimism. New home building has been strong here because of a ready market for selling existing houses, as residents move into newer or larger quarters. However, new home purchases often are tied to a contingent ability to sell currently occupied and older homes and the inability to sell some older homes is beginning to surface as a problem, because of mortgage rates now topping 10 percent.

"As soon as that plug is pulled, there will be a slowdown in building new homes," one businessman stated.

James O'Brien, resident manager and vice president of Coldwell Banker's office in Washington, forecasts that residential development "will be substantially and dramatically slowed."

John T. Hazel, a partner in Hazel, Backhorn & Hanes, agrees that "there is no question that the current interest rates will flatten things out for a period of time." But the crunch of '79 won't be so bad as in the early 1970s, because the current stock of unsold homes is minimal, Hazel adds. In particular, he notes that 7,000 condominium units were unsold in 1974 and 1975, a situation not duplicated today.

In addition, as interest rates head lower later this year, there will be renewed home purchasing and that should contribute to an even more fruitful local economy in 1980. Indeed, the bigger local housing problem may be the continued impact on inner-city D.C. residents of renovations and rehabilitations of older homes that force existing family residents out in favor of fewer numbers of younger, more affluent people, causing a decline in the city's population base. Fitzgerald, of Independence S&L, calls this "an escalation of refugees... a major issue," leading not only to displacement but higher housing costs.

These developments are taking place in the wake of a solid year of business and economic expansion for the metropolitan region, one which saw new administrations elected in D.C. and Maryland that are committed to more aggressive programs to attract jobs.

Virginia continued to show how this process works, announcing in 1978 more than 100 new or expanded manufacturing firms with 9,133 eventual new jobs and 22 firms making investments of $2 million or more.

Moreover, business leaders in the Washington and Baltimore areas have banded together to promote a new regional "common market," and are planning on a $600,000 program of selling the area to national and international business and associations, starting this year.

Builder Oliver T. Carr Jr., new president of the Metropolitan Washington Board of Trade, says all of these factors indicate that 1979 "might eve be a great year" for this area. Because of the proposed D.C. convention center, the expansion of subway operations and the continued influx of new corporate or association offices, Carr states: "Washington is on the grow!"