The clues to long-term weather prediction can be found in the world's oceans.

Providing long-term storage for much of the planet's heat, the oceans are a major driver of everyday weather patterns as well as extreme events with damaging impacts. Researchers studying the Earth system are making landmark progress in improving understanding of the often subtle influences of the oceans on weather, particularly on subseasonal (weeks) to seasonal (months) timescales. 

— May 2018