longer term flooding over several days due to rainfall over an extended time period show melt or ice jams
Five hundred year flood
an area has a 0.2% chance (1 in 500) of a flood every year.
Short term flooding caused by heavy rainfall in a short time period (usually 6 hours or less) or a dam failure.
Issued when flooding is possible but not imminent or occurring.
Issued when flooding is imminent or occurring.
A very large ocean wave caused by an under water earthquake or volcanic eruption.
The lowest point between waves.
a surge wave or billow
a narrow inlet of the sea between cliffs or steep slopes.
the top a wave.