Stocks rose sharply on Thursday, wrapping up a big week of gains, after the Federal Reserve detailed a bevy of programs to support the economy during the shutdowns from the coronavirus pandemic. The S&P 500 gained 1.5% to close at 2,789.82 while the Dow Jones Industrial Average advanced 285.80 points, or 1.2%, to 23,719.37. The Nasdaq Composite closed 0.8% higher at 8,153.58. The U.S. stock market will be closed Friday due to Good Friday. For the week, the S&P 500 surged 12.1%. That was its biggest one-week gain since 1974, when it rallied more than 14%. The Nasdaq had its best week since 2009, jumping 10.6%. The Dow soared more than 12% for one of its biggest weekly gains on record.

"It's been a strong week in equities and probably for good reason," said Terry Sandven, chief equity strategist at U.S. Bank Wealth Management. "Many stocks were widely considered to be in oversold, and then you've got policy assistance that's in motion at the Fed and in fiscal policy." "That's clearly helping sentiment, but we still find it difficult to get overly bullish when the duration of COVID-19 remains unknown," Sandven added. The Fed announced a slew of programs, including loans geared towards small and medium sized businesses, that will total up to $2.3 trillion. The central bank also gave more details on its plans to buy investment-grade and now even junk bonds. "This Fed is the most aggressive Fed. They do not want to be known as the reason why we went into a depression," CNBC's Jim Cramer said on "Squawk Box" on Thursday. "I'm very impressed. The Fed is on its game and this is what is needed because we got to fight off a depression, we got to get America open for business." Thursday's announcement was enough to outweigh another massive jump in weekly jobless claims. More than 6 million Americans filed for unemployment benefits last week. Economists expected an increase of 5 million. The latest data built on the record-shattering prior two readings of 6.6 million and 3.3 million.

Virus outlook improves

Wall Street's weekly surge came amid increasing hope that the situation around the coronavirus was improving. In recent days, the number of new daily confirmed cases has dropped globally and in the U.S. New York state has also reported a decline in its virus-related hospitalization rate.

Treasury Secretary Steven Mnuchin also told CNBC on Thursday the U.S. economy could be re-opened in May. He noted the department was doing "everything necessary that American companies and American workers can be open for business and that they have the liquidity that they need to operate their business in the interim." But some believe that stocks are now getting ahead of themselves and investors should exercise caution. "I think this is kind of buy the rumor and potentially we sell the news when reality sets in of what we are going to see what's on the other side," billionaire investor Mark Cuban said Wednesday on CNBC's "Closing Bell." "I think people are naturally optimistic right now in terms of the market. I just don't think they're really factoring in what we're going to see on the other side," he added.

JPMorgan Chase jumped nearly 9% to lead the Dow higher on Thursday. Dow Inc gained 5.1% while Goldman Sachs advanced 4.1%. Financials were the best-performing sector in the S&P 500, gaining more than 5%. After Thursday's rally, the Dow is up more than 27% from its March closing low, but still down 16.9% this year. "The stock market is at a very uncertain point now. The impact of the coronavirus on future earnings is yet to be determined. We aren't out of the woods," said Nancy Davis, chief investment officer at Quadratic Capital.