There's a lot of enthusiasm in the market. And it's driving gains in some surprising stocks.
Even Best Buy, a stock that's almost always in somebody's crosshairs gained 25% ytd.
Yet, earlier this month, the company slashed its expectations for 2013 free cash flow after it had to pay for inventory earlier than expected.
What's the deal?
"These are all good questions and they need to be answered," said Cramer.
"One way to answer the overall conundrum of these moves is to write them off to froth," said the Mad Money host. In other words, unseasoned bargain hunters may be taking shots at these companies hoping for a game of catch-up.
"Another reason might be because they were vastly oversold last year," Cramer added. That is, some investors may believe they deserve to command a higher price.
"There's also the possibility of a major turn at hand," Cramer said.
All these explanations sound plausible – all of them. And that's exactly the problem. "There isn't anything specific that explains their turns," Cramer said.
And because the catalysts are unclear – Cramer believes the upward momentum could come to a screeching halt. That he says, is especially true since it seems there's nothing fundamental driving the sharp advance.
Now, that's not to say there's couldn't be further gains – it's just that Cramer thinks when the momentum breaks – there's little to buoy the stocks at current levels.
And Cramer is concerned that momentum could break at any time.
"I think RIM, H-P and Best Buy are all susceptible to giving up at least some of their recent gains. I think at this point you have to stay sidelined."
However, that doesn't mean Cramer thinks these stocks are a short – he doesn't. "This may be the most important takeaway," he added. "The days when these were a good short? They are over."
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