US stocks jump but face "more downside risk over the next few weeks"

The S&P 500 rose 1.2 percent on Monday, leaving it just 3.25 percent below its 52-week intraday high.

Despite the impressive rally, some analysts are not convinced that the rebound so far is sustainable.

Matt Maley, equity strategist at Miller Tabak, wrote on CNBC that the "bounce has been nothing more than what we typically see on the heels of a miniature 'crash'".

Chris Watling, chief executive of Longview Economics, told CNBC that market models show a "third wave" of the market correction is coming.

"There's huge complacency," he said, adding that "there's probably some more downside risk over the next few weeks".