A flood of imports drawn into the United States by the strong dollar in January completely overwhelmed the best export performance in more than three years, as the merchandise trade deficit rose to $10.3 billion, the Commerce Department reported yesterday.

January's trade deficit, which was $2.3 billion over December's $8 billion total, led to predictions that the continued strength of the dollar and the robust U.S. economy would add up to continued splashes of red ink for 1985.

The dollar rallied on most major money markets yesterday after concerted intervention efforts by European banks had pressed it sharply lower on Wednesday. The dollar, however, failed to regain its peaks of earlier this week.

Most experts agreed it would be difficult to reverse the advance of the dollar by intervention alone if the U.S. economy continues to outpace Europe's. This draws capital investment money to the United States, increasing the price of the dollar.

The dollar increased 10 percent last year and another 9 percent since December, Commerce Secretary Malcolm Baldrige said.

The value of the dollar also is serving as a constraint on Federal Reserve policy-makers concerned about the very rapid growth of the money supply. Any overt attempt to slow down the surging money supply would elevate interest rates, which could send the dollar even higher.

With the dollar expected to remain strong, most analysts predicted that this year's trade deficit would surpass the 1984 record of $123.3 billion.

Baldrige forecast that the yearly trade deficit could reach $140 billion, while David Ernst of Evans Econometrics predicted it would go even higher, to $145 billion. But Jerry Jasinowski of the National Association of Manufacturers was more conservative, saying the 1985 trade deficit would reach $130 billion.

"Everybody sees the trade deficit getting worse because the dollar is going to remain strong and we are growing faster than everybody else," said Michael Evans of Evans Econometrics.

A strong dollar makes foreign goods less expensive in the United States, drawing in imports, while the price of U.S. products increases in overseas currencies, making them less competitive. Top-of-the-line European cars, for instance, came into the United States in surprisingly strong numbers in January because the high dollar made these expensive cars more affordable, said Commerce Department economist David Lund.

"Despite the high dollar, total foreign sales grew 9 percent during 1984, and I expect a similar increase this year," said Baldrige, pointing to the only cheerful news in the monthly trade figures.

While the flow of cheap imports helps to dampen inflationary trends, they undercut American manufacturers' sales in their home market and act to hold down the rate of economic growth. Robert Gough, a senior vice president with Data Resources Inc. estimated the soaring trade deficit could lower this year's growth in the gross national product by as much as 1 percent.

Although January's $19.4 billion in exports were the highest since September 1981, analysts said they have a long way to go before overseas sales will begin pulling the U.S. trade figures out of the red.

"The further deterioration of the trade deficit reflects a new surge in imports brought on by the speedup in economic activity in the fourth quarter," said Jasinowski, the NAM's chief economist.

The United States once again ran up its largest deficit with Japan -- $3.7 billion, which on an annual basis would increase last year's record $36.8 billion U.S. trade imbalance with that nation to $44.4 billion.

The continued increase in that deficit comes as the United States and Japan, its major Pacific ally, are in the midst of a series of contentious high-level trade talks. President Reagan, moreover, is expected to decide shortly, perhaps as soon as today, whether Japan should extend for a fifth year its quotas on auto exports to the United States when they expire March 31.

His Cabinet trade advisers recommended that the so-called "voluntary restraint agreement" be dropped, although three of the four major U.S. auto makers and the United Auto Workers union want them continued.

The high-level trade talks arose from the agreement in January by Reagan and Prime Minister Yasuhiro Nakasone to open the Japanese market to highly competitive U.S. imports in four areas -- telecommunications, wood and paper products, sophisticated electronics and pharmaceuticals, and medical equipment.

The trade deficits with Western Europe, Taiwan and the OPEC nations also increased in January over December, while the deficit with Canada declined.

Imports soared to $29.7 billion despite a 3.3 percent decline in the value of petroleum imports. The United States imported an average of 100,000 fewer barrels of oil a day in January than it did in December, and the price per barrel declined by 36 cents.

Leading imports were telecomunications equipment, passenger cars, airplanes and iron and steel products.

Leading exports were electronic machinery, office machines and automatic data processing equipment; cars; fertilizers and coal. There were, however, decreases in overseas sales of aircraft, tobacco and wheat.