spring tide

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The exceptionally high and low tides that occur at the time of the new moon or the full moon when the sun, moon, and earth are approximately aligned.
• noun A great flood or rush, as of emotion.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The tide which occurs when the moon is new or full; the effects of the Sun and moon being reinforced this type of tide is of maximum range.