Nic Lonsdale, duty watch manager at Portland Coastguard, said: "We are urging people to observe the warning signs and stay away from the edge." The cliffs at Durdle Door and Lulworth have been crumbling since the start of year.
In January, the steps to the famous landmark collapsed. Earlier this month, coastguards warned that the path was beginning to fall away.
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Pollen levels are very high
Showers continuing to clear this evening for a mostly dry night with clear spells.
Heavy showers clearing for a dry night ahead.