State Rep. Denny Coffman announced Monday that he will resign from office later this month for family reasons.

Coffman, whose wife died earlier this year, said his daughter faces a medical issue. The state House said in a statement that his resignation is effective Dec. 20.

Gov. Neil Abercrombie will appoint Coffman’s replacement.

Coffman (D, Naalehu-Captain Cook-Keauhou), who was first elected in 2008, is a respected voice on environmental issues. He served as the chairman of the House Energy and Environmental Protection Committee during the 2012 session.

"I am extremely honored to have been elected by the people of Hawaii island and to serve three terms in the Legislature. It is with a heavy heart that I made this decision but as a father and grandfather, I am firmly committed to my family and will be there for my daughters and grandchildren in their time of need. I leave knowing that I have represented the communities of Hawaii island and the state to the best of my ability," Coffman said in a statement.

Abercrombie praised Coffman for his service.

"Denny served our country and state with great honor and strength of purpose. He represented the people of Hawaii island well and helped set the state on a viable path to a responsible and economically sustainable energy policy, which will benefit generations to come," the governor said in a statement.

"While I was saddened to hear of his decision to step down as a member of the House, I recognize, as does anyone who knows him, that as a father and grandfather matters of the family take precedence. The people of Hawaii are thankful for his service and leadership, and we offer our deepest aloha to his family."

Under state law, Hawaii County Demo­crats will be able to forward three potential candidates to Abercrombie for his review. The governor has 60 days to name a replacement.