Target's ( TGT) monthly sales may again miss the mark.

The discount-retail giant said Monday that it now expects October same-store sales growth of 2% to 4%, below its forecast of 3% to 5% given a week and a half ago.

The Minneapolis-based company said its new projection is based on "greater-than-normal daily volatility," disappointing sales in the past two weeks and its expectations for the remainder of the month. The October selling period runs from Oct. 7 to Nov. 3.

In September, Target also cut its sales expectations during a mid-month update. The company ended up reporting a 1.2% rise in same-store sales for the month, and it also said it didn't expect to meet earnings expectations for the year.

Overall, September was a lackluster sales month for retailers, with economic troubles hitting customer wallets and unseasonably warm weather hurting traffic. But October was expected to show somewhat of an improvement, and Target's warning casts a pall over that optimism.

Shares of Target were down 1.4% to $61.55 in after-hours trading.