Tides Explained
Spring tides are the strongest regular tides in the lunar cycle. They happen when the Sun, Moon and Earth align,
producing higher high tides, lower low tides and the greatest tidal range of the month.
What Are Spring Tides?
Spring tides are tides with the largest difference between high tide and low tide. During a spring tide,
high tides rise higher than usual and low tides fall lower than usual.
The word “spring” does not refer to the season. It comes from the idea of the sea “springing forth” during
stronger tidal conditions.
Why Do Spring Tides Happen?
Spring tides happen when the gravitational pull of the Moon and the Sun combine. This occurs when the Sun,
Moon and Earth are nearly aligned, allowing lunar and solar tidal forces to reinforce each other.
Because the Moon is the main driver of tides and the Sun adds extra pull during alignment, the ocean responds
with a larger tidal bulge. The result is a greater tidal range along many coastlines.
Spring Tides During New Moon and Full Moon
Spring tides occur twice each lunar month: around the new moon and around the full moon.
- New moon spring tide: the Moon is between Earth and the Sun, so their tidal forces line up.
- Full moon spring tide: Earth is between the Moon and the Sun, but their tidal forces still align.
In both cases, the alignment increases tidal range. This is why unusually high tides often cluster around
new and full moon phases.
Spring Tides vs. Neap Tides
Spring tides are the opposite of neap tides.
Spring tides produce the largest tidal range, while neap tides produce the smallest tidal range.
Neap tides happen when the Sun and Moon pull at right angles, partly canceling each other’s tidal influence.
Spring tides happen when their forces reinforce each other.
Are Spring Tides Dangerous?
Spring tides are predictable, but they can become hazardous when combined with storms, strong winds, low pressure,
storm surge or sea-level rise. In vulnerable coastal areas, spring tides can worsen flooding, erosion and dangerous
tidal currents.
They can also expose larger areas of mudflats and reefs at low tide, then flood them quickly as the tide returns.
This can trap walkers, anglers and beach visitors who underestimate how fast tidal water moves.
Spring Tides and Coastal Flooding
A spring tide does not need a storm to raise sea level higher than usual, but the worst impacts usually happen
when a spring tide overlaps with bad weather. A storm arriving at peak high tide can push water farther inland
than either event would alone.
This is why spring tides are important for understanding
coastal erosion,
extreme ocean waves and
tides.
Key Signs of a Spring Tide
- High tides are higher than normal.
- Low tides are lower than normal.
- The tidal range is at or near its monthly maximum.
- Strong tidal currents may occur in channels, estuaries and inlets.
- Coastal flooding risk increases if storms or strong onshore winds are present.
FAQ: Spring Tides Explained
What is a spring tide?
A spring tide is a tide with an unusually large tidal range, producing higher high tides and lower low tides.
When do spring tides happen?
Spring tides happen around the new moon and full moon, when the Sun, Moon and Earth are aligned.
Does spring tide mean it happens in spring?
No. Spring tides happen throughout the year. The name refers to the sea “springing” higher and lower than usual.
Are spring tides the same as king tides?
Not exactly. King tide is an informal term for especially high tides, often the highest predicted tides of the year.
Many king tides occur during strong spring tide periods.
Can spring tides cause coastal flooding?
Yes. Spring tides can contribute to coastal flooding, especially when they coincide with storms, storm surge,
strong winds or sea-level rise.
