(Adds closing prices, market details)

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Benchmarks endure topsy-turvy day ahead of Trump tariff

event

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Airlines drop after Jefferies downgrades on outlook

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J&J falls after judge rejects $10 billion baby-powder

settlement

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Big gains for recent IPO names CoreWeave ( CRWV ), Newsmax ( NMAX )

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Indexes: Dow down 0.03%, S&P 500 up 0.38%, Nasdaq up 0.87%

By David French

April 1 (Reuters) - The S&P 500 and the Nasdaq Composite

both closed higher on Tuesday, after a topsy-turvy day on Wall

Street dominated by investor angst ahead of the impending tariff

announcements from the Trump administration.

Financial markets have been volatile in recent weeks as

investors assessed the economic fallout of U.S. President Donald

Trump's extensive tariff plans, which have sparked worries about

a U.S. economic slowdown and higher inflation.

Some of the uncertainty that has gripped markets is expected

to dissipate after Trump unveils his tariff plan on Wednesday

during an event in the Rose Garden, currently scheduled for 4

p.m. EDT.

However, while clarity on the specific tariff measures will

be welcomed by investors, the overall backdrop is set to remain

highly uncertain, making it difficult for markets to agree on

directionality.

"The fact of the matter is sentiment is washed out and

positioning is still fairly light," said Garrett Melson,

portfolio strategist at Natixis Investment Managers Solutions.

"I don't think we're going to get the type of clarity that

investors and business leaders want," he added. "And at the end

of the day, we spend a lot of time talking about tariffs, but

the bigger story is we are dealing with an economy that is not

firing on all cylinders."

For now, according to Melson, this means investors are

"sitting on their hands, biding their time."

This attitude was reflected in the three Wall Street

benchmarks on Tuesday, which swung between positive and negative

territory throughout much of the day, before finishing the

afternoon with some decent momentum.

The S&P 500 gained 21.22 points, or 0.38%, to

5,633.07 points, while the Nasdaq Composite climbed

150.60 points, or 0.87%, to 17,449.89. The Dow Jones Industrial

Average edged down 11.80 points, or 0.03%, to 41,989.96.

Gains on the Nasdaq and S&P 500 were fueled by rebounds in

technology stocks, which have been among the most punished in

the opening weeks of the year.

Big-tech advances were led by Tesla, which climbed 3.6%

ahead of its first-quarter vehicle deliveries report on

Wednesday. There were also gains for other Magnificent Seven

stocks including Amazon.com ( AMZN ), Microsoft ( MSFT ) and

Meta Platforms ( META ), which rose between 1% and 1.8%.

The S&P, however, was also weighed down by falls in

healthcare and airlines.

Johnson & Johnson ( JNJ ) was the worst performer on the S&P

500, falling 7.6% and dragging the broader healthcare sector

down 1.8% to the bottom of the 11 S&P sectors. A U.S.

bankruptcy judge rejected the company's $10 billion proposal to

end tens of thousands of lawsuits alleging that its baby powder

and other talc products cause ovarian cancer.

Meanwhile, Delta Air Lines ( DAL ), American Airlines ( AAL )

and Southwest Airlines ( LUV ) all dropped between 2.4% and

5.9%, as Jefferies analysts downgraded stocks amid concerns that

economic uncertainty could disrupt both business and retail

travel demand.

Among single stocks, there were big gains posted by some of

the newest public companies.

Conservative news outlet Newsmax ( NMAX ) soared for the second

straight day, jumping 208%, following a more than 700% surge in

its NYSE debut on Monday.

CoreWeave ( CRWV ), which has had a more rocky start since

debuting as a public company on Friday, climbed 37.3% to trade

back above the IPO price of the artificial-intelligence

startup.

Volume on U.S. exchanges was 15.09 billion shares, compared

with the 15.83 billion average for the full session over the

last 20 trading days.