JERUSALEM, DEC. 29 -- Soviet immigrants are pouring into Israel this weekend at the rate of 100 an hour, providing a dramatic finale to a year in which mass immigration has suddenly brought a new era of turmoil and dynamic change to the Jewish state.

By Monday, with dozens of flights landing around the clock, officials expect to welcome the 200,000th immigrant to Israel this year, an event that almost no one in the country could have imagined a year ago. The total, which will include about 185,000 Soviets, represents more than 5 percent of Israel's total Jewish population and is the highest since 1949, the year after the state was founded.

Alarmed by the collapse of the Soviet economy as well as burgeoning antisemitism, Soviet Jews who had delayed their departure to Israel in recent months are now rushing for seats on planes and trains to transit points in Eastern Europe, officials said. Twelve thousand are expected this week alone, and up to 40,000 for the month of December -- both records in the history of Jewish immigration to Israel.

Next year, say officials of the government and the Jewish Agency, between 300,000 and 400,000 Soviet Jews will arrive here if the routes out remain open. About 1 million people in the Soviet Union already have requested and received official invitations to emigrate to Israel. "We are going to get them out as quickly as we can, regardless of the difficulties it creates here," said Simcha Dinitz, the chairman of the Jewish Agency, which is handling the job of transport. "Because if we wait, the doors could close and it could be too late."

Despite the Persian Gulf crisis and the surging intifada, or Arab uprising in the occupied territories, immigration has become the dominant force in Israel's economy and politics. Even with the threats of war and world recession, the economy is booming from a surge of housing construction and other investment, with growth expected to climb from 5 percent this year to 8 percent in 1991.

In national politics, the immigrants -- who could constitute a fifth of the electorate by the time of the next scheduled election in 1992 -- have become the object of a fierce tug-of-war among the hawkish and dovish, secular and religious factions whose battles have stalemated the country for a decade. Many politicians believe the Soviets will settle Israel's long debate over the country's rightful boundaries and Jewish identity, though no one is yet sure which side they will favor.

For now, the clearest effect of the immigration has been to plunge the country into one of the most severe trials it has ever faced. Politicians of both the left and the right routinely declare that Israel's ability to absorb the immigration wave will determine its future. And yet there is a widespread belief here that the government has handled the influx slowly and inefficiently, setting the stage for chaotic conditions in coming months.

"The government is clearly failing to meet the challenge of absorbing the masses. A demographic blessing is turning into a demographic nightmare," the weekly Jerusalem Report said in a comment typical of the Israeli media's evaluation of the absorption effort. Added the newspaper Haaretz: "Even if {the Soviets} are prepared emotionally for the shock that awaits any immigrant to a new country, the reality they encounter in Israel will be beyond their worst nightmares."

Already, the signs of overload are everywhere. Three and four Russian families are sharing many apartments in urban areas because of a critical shortage of housing, and tent cities of homeless have stood since last summer in many places around the country. Army bases, hotels and kibbutzes are now being prepared to house immigrants.

Government offices charged with helping new immigrants often resemble the shortage-starved shops of Moscow, with long lines of plaintiffs forming at their doors before dawn each day. Immigrants already have held protest demonstrations and longtime Israelis have demonstrated against the location of temporary housing for Soviets in their neighborhoods.

Despite the incipient economic surge, unemployment has risen to 10 percent and half of all Soviets looking for jobs have failed to find them. Schools are planning shortened class hours and double shifts to handle their 15,000 new students, and delays for treatment are lengthening in hospitals. Meanwhile, veteran Israelis are facing a bitter package of tax increases and cuts in services from a cash-strapped government.

The Soviet arrivals are so far showing remarkable resilience in the face of the hardships. They have surprised the government with their willingness to crowd into available apartments and to replace migrant Arab workers in low-paying, menial jobs that unemployed Israelis refuse to accept. "It's hard, but it's still better than Russia," said Misha Pelvitzsky, who arrived in January with a family of three and already has co-founded a small business. "We're still glad to have gotten out."

Surveys by the Jewish Agency show an extraordinary supply of talent among the immigrants. Of the first 100,000 to arrive from the Soviet Union this year, 22,000 were university graduates. By September, Israel, with a population of only 4.5 million, had aquired 3,500 new doctors, 13,000 engineers and architects, 2,500 nurses and more than 5,000 teachers, including 65 university professors.

Though most Israelis still welcome the Soviets, a backlash is also visible, especially among the communities of ultra-Orthodox and non-European Jews whose interests seem most at risk from the overwhelmingly secular and European immigrants. Ironically, one of the chief spokesmen of this minority is Absorption Minister Yitzhak Peretz, an ultra-Orthodox non-European rabbi who has insistently claimed that at least 30 percent of the arriving Soviets are "not Jewish" and should not be coming to Israel. Officially, the government and Jewish Agency say that only 4 percent of the immigrants are non-Jews.

For many Israelis, the pain of the absorption has been compounded by the specter of such political quarrels and bureaucratic snarls within the right-wing government of Prime Minister Yitzhak Shamir. Competing ministers have openly feuded over plans for housing and jobs, critics say, unchecked by their 75-year-old and incorrigibly low-key prime minister. In the latest spat, Absorption Minister Peretz refused for several weeks to attend meetings or present his ministry's plan for next year because, he maintained, he had been insulted by Housing Minister Ariel Sharon, who also functions as the government's immigration czar.

The worst snafus have been in housing. Expecting only 40,000 immigrants to arrive this year, the government initially planned 45,000 housing starts by next March, then belatedly decided to import thousands of prefabricated and mobile homes. As the year ends, however, less than half of the planned housing is under construction, while only 400 imported homes have arrived. Meanwhile, independent experts say Israel will need 300,000 new homes for the immigrants expected to arrive by the end of 1992.

"Any government facing a challenge of the magnitude that we have would have had a lot of trouble," said the Jewish Agency's Dinitz in an interview. "But we lost months of very precious time and . . . we may have serious problems."

In its desperation to jump-start construction, the government has now largely abandoned efforts to reform Israel's quasi-socialist economy with free markets and launched into the building of state housing. That program, combined with job-creation schemes yet to be implemented, spending on new schools, hospitals and roads, and the substantial state subsidies being paid to the immigrants, will bring the cost of the immigration to more than $33 billion over three years, Dinitz estimated.

Having already increased the budget deficit to double that of the United States in percentage terms, and raised taxes to the highest level in the Western world, the government is now hoping to persuade world Jewry and foreign banks and governments to give it billions of dollars in loans and grants. Finance Minister Yitzhak Modai recently said Israel would need up to $8 billion from outside sources over the next few years.

So far, while Jewish groups around the world have stepped up donations dramatically, Shamir's government has had trouble winning aid from the United States beyond the $3 billion in annual grants it already receives. After months of delay, the Bush administration reluctantly agreed to guarantee $400 million in bank loans to Israel for housing construction but has been slow to implement the program. Washington has not responded to Shamir's request that it provide far more loan guarantees next year.

Apart from U.S. budgetary problems, the Israeli fund-raising campaign is hampered by political obstacles. Before providing funds for housing, the Bush administration has wanted guarantees from Israel that Soviet immigrants will not be used to populate Israeli settlements in the occupied West Bank and Gaza Strip -- a prospect that has raised alarm around the Arab world.

Shamir and his right-wing ministers have responded with general pledges not to "direct" immigrants to the territories except for East Jerusalem and the Golan Heights, which Israel has annexed. Official figures indicate, however, that more than 6,000 immigrants have settled beyond Israel's internationally recognized borders this year, including 4,500 in Arab East Jerusalem. The government is planning 2,500 more housing units for the territories and several thousand in East Jerusalem.

Shamir and other government spokesmen deny Arab charges that they intend to use the immigration to further their dream of a "greater Israel" including the occupied territories and possibly other lands. But the veteran prime minister has publicly articulated just such a vision several times in the last year.

"The past leaders of the {Likud} Party left us a clear message," Shamir said in one speech last month, "to keep the land of Israel from the {Mediterranean} sea to the Jordan {River}, for future generations and for the mass immigration and for the Jewish people, most of whom will be gathered into this country."