Updated from Oct. 3

Wet Seal ( WTSLA) shares plunged 19% Thursday after the women's apparel retailer slashed its third-quarter estimates amid weak sales and heavy markdowns.

Shares recently were down 77 cents to $3.22, on more than four times their average daily volume.

Late Wednesday, Wet Seal projected third-quarter earnings ranging from break-even to 2 cents a share, down from its prior estimate of 7 to 10 cents a share. Analysts, on average, predicted earnings of 9 cents a share.

The Foothill Ranch, Calif., company, which owns the Wet Seal and Arden B chains, said it expects to record a same-store sales decline of 7.5% to 8.5% for September. Previously, Wet Seal projected results ranging from a 1% decline to a 3% rise.

The company sees more declines for October, projecting a 2% to 6% drop in same-store sales, or sales at stores open at least a year, for the month.

"During September, we have continued to experience lower year-over-year average store transaction counts," said CEO Joel Waller in a statement. "This, along with higher than originally expected promotional activity, has resulted in lowered comparable store sales and earnings expectations for the third quarter."

On Thursday, Cowen downgraded the stock to neutral from outperform, while JPMorgan cut its rating to neutral from overweight.

JPMorgan also downgraded teen retailer Charlotte Russe ( CHIC) to neutral from overweight due to Wet Seal's sales stumble. The firm said Charlotte Russe may also have seen a sales slowdown in September and could miss profit targets for the quarter.

Shares of Charlotte Russe were tumbling $1.56, or 9.8%, to $14.38.