With the recession-proof myth all but shattered by the latest economic downturn, business and government officials in metropolitan Washington are predicting the start of a moderate recovery in the next four to six months.

Most observers believe that even though the local economy remains relatively stagnant compared with earlier downturns, it will bounce back much quicker than it will in most areas because of built-in strengths.

"I think we will have a very moderate recovery for 1983, and I think it will start in the last quarter of 1982," observed Billy Cook, associate director of the D.C. Department of Finance and Revenue.

The intensity of the recovery will be "very moderate" and "the rebound will be a slow process," says Kenneth M. Gassman Jr., assistant vice president at Wheat First Securities, a leading securities dealer in the Middle Atlantic region.

Economists and most businessmen agree that only moderate improvement will be apparent in key sectors of the local economy, such as employment, retail sales and construction.

As a rule, the local economy is seldom seriously affected by national economic downturns. That no longer holds true, some local economists believe, because of substantial reductions in government employment.

Indeed, statistics indicate that government employment is declining faster in the Washington Standard Metropolitan Statistical Area than it is in the District, where the overall unemployment rate is much higher.

In the first half of the year, for example, government employment in the District was down 2.9 percent, compared with 3.5 percent in the SMSA. And the Maryland suburbs were harder hit than Northern Virginia communities.

Overall, the latest available figures show that the unemployment rate in the District remained constant at 11.4 percent between June and July. The area's unemployment rate for the same period showed a slight decline, from 6.4 percent to 6.3 percent.

Meanwhile, the number of jobs in the metropolitan area declined by more than 11,000 between July 1981 and July 1982.

With government employment still uncertain and a slow recovery predicted for other key areas, improvement in the unemployment rate is expected to be moderate at best. District officials, for example, predict a 9.5 percent unemployment rate next year.

At the same time, federal employment may decline by as much as 2 percent in 1983, forecasters believe.

Although the outlook appears to be somewhat brighter for retail sales in the fourth quarter and beyond, the keys to improvement there are unemployment and consumer confidence. "Where there is less disposable income, the less people are going to spend," said one local financial officer.

Despite being one of the country's richest retail markets, metropolitan Washington has been affected by the same malady that has depressed sales nationwide. In fact, figures maintained by the Greater Washington Board of Trade show that retail sales figures for the past month have been "up only a small percentage" after increasing only 5 percent in the prior four-week period.

For the most part, retail sales have been spotty since the beginning of the year. Nonetheless, the pattern is beginning to "flatten out," according to a board of trade official.

"Sales aren't strong, but we aren't taking any big dips," added Leonard Kolodny, manager of the Board of Trade's retail bureau.

Regional retailers likely to benefit earliest in the recovery are catalogue showrooms, fast food service outlets, do-it-yourself home improvement stores and specialty stores, said Gassman of Wheat First Securities.

By the end of the next quarter, however, sales in general should show some improvement, retailers believe.

One measure of the moderate rise being predicted is that D.C. government officials expect an increase of between 3.5 percent and 4 percent in sales tax revenues at year's end, compared with a 17 percent rise in 1981.

Those estimates are typical of modest projections being made for other tax revenues in the District. As an example, revenue from the personal income tax this year is expected to rise only 7 percent. The increase a year ago more than doubled that.

Much of the optimism pointing to a moderate recovery over the next year is based on recent signs of relief from interest-rate pressures. Certainly, if interest rates continue to fall, there probably will be slight improvement in the residential construction sector, most observers believe.

On the other hand, some economists are forecasting a flat housing market for the next several months.

Meanwhile, the outlook for commercial construction, in the view of several developers and leasing specialists, appears to be brighter.

Their optimism is blunted, however, by the concern that some bankers have expressed privately on the subject of construction loans. At best, the near-term outlook appears uncertain for the office development and leasing market downtown.

Although the pace seems to have picked up, leasing the vast amount of space still available in new buildings or those coming on line this year continues to be a serious problem for some developers.

Some new buildings are less than 70 percent leased. And saddled with high carrying costs, some owners are forced to renegotiate rents downward.

Although acknowledging problems resulting from overbuilding, developers and leasing experts say the downtown office market is on the verge of recovery from the glut of space and high rents.

"Our forecast for 1983 is one of optimism based on discussions we've had with people about the delivery of space," notes Philip R. Carr, vice president of the Oliver T. Carr Co., one of the area's biggest developers.

Developers say they detect greater enthusiasm in the leasing market, a sharp contrast to the situation that existed only a few weeks ago when building owners were lamenting the huge supply of unleased space in downtown buildings.

Skyrocketing rental rates as much as overbuilding hurt the downtown office market. There is strong evidence now, however, that pressure to unload an oversupply of space is forcing rents down to more acceptable levels.

"Now, we're seeing a normalization or a reverse to the $20 a square foot rentals," observed George F. Voris, sales manager at Coldwell Banker, commercial real estate specialists. "There are deals being done in the $30 range but also a lot in the $20s," Voris added. "If you analyze the market, you'll really see prices stabilizing."

Another encouraging sign for the office rental market next year is that the absorption rate has practically returned to normal, concerns about a glut notwithstanding.

"What we're seeing now is that office users are taking down bigger chunks," said Ken McVearry, vice president and general manager here of Coldwell Banker.

An analysis of the office building market shows that developers outstripped demand by constructing more as well as larger buildings. The normal absorption rate here is about 4 million square feet, a level that will be matched this year.

Meanwhile, observed Carr, "We seem to be bottoming out of the recession and that will not only affect existing space but new space."

Still, all bets on a moderate recovery in most major sectors of the region's economy are tied to interest rates as a caveat. If rates continue to decline through the end of the year, say most business and government officials, the region's economy should recover at a moderate rate in 1983.