Fairfax and Montgomery county police reported yesterday that the amounts of drugs seized in 1987 were double and nearly triple the previous year's figures, with cocaine being bought and sold in restaurants, shopping centers and homes in record volumes.

Fairfax police confiscated $3 million worth of drugs last year, double the amount seized in 1986. A total of 273 people were arrested for distributing drugs in Fairfax in 1987, twice as many as the year before. Police say that even the telephone calls they receive point to a growing drug problem, with calls related to drug activities running 400 percent more than those in the early 1980s.

In Montgomery, the increase has been even more dramatic. In 1986, $2.4 million worth of drugs was seized; last year police confiscated $6.9 million worth of illegal substances.

While the total number of drug-related arrests in Montgomery for 1987 has not been tallied, county police said there was an unusually high number of major drug arrests last year. Said Sgt. Wayne Cleveland: "The reason for the increase is that the whole area, including Montgomery County, is being flooded with cocaine."

Throughout the Washington area, cocaine, and its derivative known as crack, accounted for the vast majority of the seizures by police.

In the District, Police Chief Maurice T. Turner Jr. announced yesterday that city police will be armed with semiautomatic weapons, in what he said was an effort to combat the drug trafficking and related violence that are "terrorizing the city."

While much of the area's drug problem has focused on the District, where $11.4 million worth of drugs was seized last year and where an alarming number of drug-related killings have occurred recently, suburban police officers say the drug problem has surfaced in their jurisdictions in a big way.

"It's naive to say that cocaine is not available in significant quantities anywhere in the Washington area," Fairfax County police Capt. William Edmonston said.

Unlike in the District, where drug sales often occur at curbside in neighborhoods known for drug trafficking, the suburban drug problem is more pervasive, Fairfax and Montgomery police say. Sales are conducted at sites throughout the counties, which rank among the wealthiest in the nation.

"It might be some rendezvous in a cocktail lounge or at some nice suburban home," said Fairfax police spokesman Warren Carmichael. "Cocaine has been seized in very large quantities in typical suburban single-family homes, town houses and apartments."

Suburban police say they have not experienced the violence related to drugs that the District has -- with 34 of the 44 homicides of 1988 linked by city police to drugs --

because the suburbs have not been invaded by out-of-town drug dealers. Most of those distributing the drugs at the street level are local residents, county police said.

Also, Montgomery County, like Fairfax, does not have an area where most drug sales occur. While sections of Rockville, Gaithersburg and Silver Spring have seen a significant number of drug arrests, Cleveland said that "there are large seizures throughout the county."

Fairfax police, emphasizing that drug arrests were made throughout the county, pinpointed Reston and the Rte. 1 corridor as high-volume areas.

Seizures ranged from less than an ounce to more than a kilogram, police said. Each police department uses a standard formula from the U.S. Drug Enforcement Administration to assign values to confiscated drugs. Currently, cocaine is given a street value of $1,200 to $1,800 an ounce, depending on its potency. Values have dropped dramatically because the drug is in greater supply; in the early 1980s, an ounce could bring up to $2,400 on the street.

The increase in suburban drug use also is detected by those serving drug abusers. At Substance Abuse Services, a public program for Falls Church and Fairfax County, 4,200 people sought help on an outpatient basis for alcohol or drug use in 1986. In 1987, 5,200 outpatients did.

"We are seeing an increase in the number of people seeking help for cocaine use," said Beverly Howard, the program director. "When there are more drugs available, more people use it and more people need help."

The national "Just Say 'No' " campaign to cut drug use apparently has not been effective in Fairfax, Edmonston said. "It is not reflected in our arrests. How it affects the younger children we don't know yet. It {reduced usage} might show up in years to come."

Howard said that in the last several years, younger people have been using drugs, particulary cocaine. Fairfax police say they are targeting elementary schools for educational programs against drug use.

Other Washington area suburbs have not completed collecting drug-related statistics for 1987, but spokesmen for Alexandria and Prince George's counties said preliminary numbers show significant increases in arrests.

In Alexandria, the number of people arrested for distributing or possessing drugs rose from 268 in 1986 to 549 in 1987.

Lt. Clark R. Price, commander of the Prince George's police vice controls division, said the value of drugs seized rose from $3.2 million in 1986 to $4.8 million in 1987.

In other crime figures released yesterday, Fairfax County showed no increase in the numbers of homicides, rapes, robberies or aggravated assaults. The best news, Fairfax police said, was the decrease in the number of fatal traffic accidents. In one year, traffic fatalities were cut from 75 to 41, a decrease attributed in part to increased use of seat belts.

However, car theft in Fairfax increased by 24 percent in 1987, a trend reflected in other area jurisdictions. Almost 2,200 cars were reported stolen in the county last year.