When Kohl's (KSS -2.45%) announced its fourth-quarter results had fallen short of expectations, you might have expected the holiday season was to blame. Starbucks (SBUX -1.02%) had already warned that foot traffic in the malls had been unusually slow, and the preliminary report from J.C. Penney (JCPN.Q) also suggested a challenging December. Kohl's holiday season was actually a tad stronger than expected, but there were a few other factors of greater concern.

The Kohl's update
On Feb. 6, Kohl's released its updated guidance for the fiscal fourth quarter. Same-store sales slipped 2% while the holiday months of November and December saw a combined 0.8% lift. In order for the performance average of the quarter from November to January to fall by 2% overall, and considering the biggest months of the year saw a 0.8% climb, January must have been pretty weak.

Kohl's stated, "January sales were significantly lower than planned as a result of lower traffic and low levels of clearance merchandise." The company also blamed its online business for higher-than-expected costs. Kohl's lowered its earnings-per-share guidance to $1.53, down from a range of $1.59 to $1.74.

Starbucks CEO Howard Schultz mentioned that the traditional foot traffic seen during the holidays for the first time gave way to "online in a major way." Perhaps this shift caused Kohl's unexpected online expenses. Starbucks itself ironically saw a 4% increase in foot traffic despite the shift away from the malls. Maybe Kohl's should put some Starbucks kiosks within its stores.

Beat the cold
Interestingly, Kohl's actually seemed to have beaten its expectations for the holiday period. For the quarter, anyway, Kohl's guided for a same-store sales performance of between flat and a decline of 2%. The 0.8% increase during the holiday months is certainly well above this range. Then again, Kohl's was open for 100 straight hours leading up to Christmas, something it has never done before, so that may have nudged same-store sales up just enough into the positive.

What is most concerning about the report for January is that January across the nation is an unusually cold month. For Kohl's, it was thought that seasonal cold meant more sales, not less. During last quarter's conference call, CEO Kevin Mansell said, "On an extremely positive note, the month of October ended the third quarter very strongly, and we significantly exceeded our plan. That strength, further fueled by seasonal weather, has continued into November."

Later, during the Q&A session of the conference call, Mansell said the October and November strength was "all driven by traffic," as "traffic trends just markedly improved." He went on to say that it was fueled in part by the seasonal weather. Maybe the unusually cold weather helps in the fall but hurts in the winter. Perhaps there is such a thing as "too cold," in which case, expect to see many more retailers report poor results due to the cold.

J.C. Penney with the same seemingly conflicting words
The whole "too cold" thing reminds me of J.C. Penney. In November, J.C. Penney saw a 10.1% spike in same-store sales. Chief Executive Mike Ullman in part credited the spike to the seasonally cold weather coming early. Fast-forward to Feb. 4, and Ullman is now mentioning that there are "significant headwinds facing all retailers this season, including unprecedented harsh weather conditions in many parts of the country." Could it be that everybody bought their winter gear from Kohl's, J.C. Penney, etc. early? Or has it gotten too cold (not to mentioned too snowed-in) to even leave the house in some areas? Perhaps it's both.

Foolish final thoughts
The unforeseen drop in same-store sales out of Kohl's in January is concerning. Fools should consider being cautious and wait for further information until we can be sure it's truly a one-month thing and not a sign of other trouble for the retailer. Meanwhile, be mindful that the weather may lead to many calendar first-quarter bad reports from retailers.

Fools tend to be long-term investors, but that doesn't mean you should enter new positions without paying attention to current events. Bad reports due to temporary circumstances like weather can make for fabulous entries. Watch for overreaction sell-offs among various retailers for potentially great long-term bargains.