Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of The Bon-Ton Stores, Inc. (NASDAQ:BONT) jumped as much as 10% today and finished 5% higher after reporting first-quarter earnings this morning.

So what: Shares opened down 4% as the department-store chain missed expectations. Sales fell 6.1% to $622.5 million on a same-store sales decline of 5.8%, below estimates at $641.7 million, while its loss widened from $1.41 a share to $1.63. Analysts had expected a loss of $1.39. CEO Brendan Hoffman cited bad weather as the major reason the company missed its own expectations, but noted positives as "traffic trends improved dramatically" in April. He also said the company made strides in the quarter despite lower sales, posting a 50-basis-point gain in gross margin to 35.3%. 

Now what: Investors seemed to buy Hoffman's argument, as shares quickly rose during the session, with the company maintaining its guidance for the full year despite a weak quarter and Hoffman pointing out several positive indicators from the company's strategies. Looking ahead, the company sees earnings of $0.40-$0.70, in line with guidance at $0.59. The market has a tendency of punishing stocks for good earnings and bad guidance, but it seems to have done the opposite this time, as Bon-Ton is in the middle of a turnaround and its future performance will weigh more than one weather-weakened quarter.