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What: Shares of closeout retailer Tuesday Morning (Nasdaq: TUES) cratered today, falling as much as 22% in intraday trading after the company offered guidance for its fiscal second quarter.

So what: The company said that sales for the December quarter came in at $279 million, down from $290 million the prior year. Same-store sales for the quarter fell 3.2%. Along with the sales figure, the company also provided a range of $0.39 to $0.41 for the quarter's earnings per share. That compares with analyst expectations of $0.49 and the previous-year's result of $0.43.

Now what: There's good reason for investors to be miffed about today's news. The December quarter is by far the company's most important in terms of both revenue and profitability, so weaker-than-expected results during that period are a big disappointment. If there's a saving grace for Tuesday Morning, it's that -- at least as of the end of last quarter -- it's still in a pretty strong financial position with little debt hanging over its head. But management will now have to prove to investors that this soft quarter isn't a sign that the company's bottom line is continuing to sputter.

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Fool contributor Matt Koppenheffer does not own shares of any of the companies mentioned. You can check out what Matt is keeping an eye on by visiting his CAPS portfolio, or you can follow Matt on Twitter @KoppTheFool or on his RSS feed. The Fool's disclosure policy prefers dividends over a sharp stick in the eye.