Complex sentence: Today surface water temperatures remain relatively constant at 21--25 ° C (70--77 ° F) and temperature and visibility remain good to around 200 m (656 ft), but the sea is known for its strong winds and unpredictable local currents.
Split into simpler sentences: Today surface water temperatures remain relatively constant at 21--25 ° C (70--77 ° F) and temperature and visibility remain good to around 200 m (656 ft). However, the sea is known for its strong winds and unpredictable local currents.