In advance of its fourth-quarter earnings announcement, UPS (NYSE:UPS) announced today that it lowered its expected full-year earnings per share to $4.57, below its previous guidance of $4.65 to $4.85.

UPS attributed this to three factors, including a compressed peak holiday season as a result of the timing of the Thanksgiving holiday, an "unprecedented level of online shopping that included a surge of last-minute orders," and the weather. Together, these resulted in higher costs as it had to employ 30,000 more temporary employees than it expected, which brought its total holiday temporary employment count to 85,000.

In total, UPS noted it delivered its most packages ever on Dec. 23, topping 31 million packages. This represented a 13% over the highest day in 2012, and it was also 7.5% more than it anticipated. In addition to the larger number of shipments, the peak day also occurred six days later than expected.

UPS concluded that while its fourth-quarter results would be lower than previously announced, it anticipated that its earnings-per-share growth in 2014 would continue to be in line with its target range of 10%-15%. It also announced it would provide further guidance when it fully releases its earnings on Jan. 30.