NEW YORK (TheStreet) -- Shares of Zumiez  (ZUMZ - Get Report)  were jumping 17.87% to $21.53 on heavy trading volume late Thursday afternoon after the company said sales in September rose 11.5% year-over-year to $75 million. 

Comparable-store sales increased 6.3% in September vs. a 1.8% decline during the same period last year. 

As a result, the Lynwood, WA-based teen retailer raised its 2016 fiscal third-quarter revenue guidance to be in the range of $216 million to $217 million, compared to its prior estimates of $209 million to $213 million. 

Wall Street is looking for $215.2 million in revenue. 

Zumiez also raised its third quarter earnings forecast to be between 29 cents and 30 cents per share, above its prior guidance of 21 cents to 26 cents per share. 

Analysts are projecting 29 cents per share for the period. 

Additionally, William Blair upgraded the stock to "outperform" from "market perform," according to TheFly.

Zumiez September results marked the company's best comparable-store sales gain since February 2015, William Blair noted. 

About 2.54 million of the company's shares changed hands so far today vs. its average volume of 437,487 shares per day.

Separately, TheStreet Ratings objectively rated this stock according to its "risk-adjusted" total return prospect over a 12-month investment horizon. Not based on the news in any given day, the rating may differ from Jim Cramer's view or that of this articles's author. 

The team rates Zumiez as a Hold with a ratings score of C. The company's strengths can be seen in multiple areas, such as its good cash flow from operations, largely solid financial position with reasonable debt levels by most measures and solid stock price performance. However, as a counter to these strengths, the team also finds weaknesses including feeble growth in the company's earnings per share, deteriorating net income and disappointing return on equity.

You can view the full analysis from the report here: ZUMZ

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