The normal rainfall is about 80 in., but as cloud-bursts are common, it may rise to 150 in.
In Leontice thalictroides (Blue Cohosh), species of Ophiopogon, Peliosanthes and Stateria, the ovary ruptures immediately after flowering, and the ovules are exposed; and in species of Cuphea the placenta ultimately bursts through the ovary and corolla, and becomes erect, bearing the exposed ovules.
One of these, called the "Bourne," bursts forth a short way above the town at irregular intervals of one to ten years or more; and after running a torrent for two or three months, as quickly vanishes.
Where the contributory drainage area exceeds 5000 acres, the discharge, even allowing for so-called " cloud-bursts," rarely or never exceeds the rate of about 300 cub.
Extreme cases of local discharge are due to the phenomena known in America as " cloud-bursts," which occasionally occur in Great Britain and result in discharges, the intensities of which have rarely been recorded by rain-gauges.