SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): April 28, 2003 OTTER TAIL CORPORATION (Exact name of registrant as specified in its charter) Minnesota 0-00368 41-0462685 (State or other jurisdiction (Commission (I.R.S. Employer of incorporation) File Number) Identification No.) 215 South Cascade Street, P.O. Box 496, Fergus Falls, MN 56538-0496 (Address of principal executive offices) (Zip Code) Registrant's telephone number, including area code: (866) 410-8780 (Former name or former address, if changed since last report.) ITEM 9. REGULATION FD DISCLOSURE. Reference is made to the Registrant's Press Release, dated April 28, 2003, which is included herewith as Exhibit 99.1. The attached Exhibit is furnished pursuant to Item 12 on Form 8-K. SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized. OTTER TAIL CORPORATION Date: April 28, 2003 By /s/ Kevin G. Moug ----------------- Kevin G. Moug Chief Financial Officer and Treasurer 2 EXHIBIT INDEX Exhibit Description of Exhibit ------- ---------------------- 99.1 Press release, dated April 28, 2003 3