Localised flooding also possible
Heavy rain and gale force winds are expected to cause problems on the Island later this week.
The Steam Packet Company is warning its services could be disrupted or cancelled on Friday, with a further update to be issued tomorrow lunchtime.
The 8.45am Ben-my-Chree crossing and the return sailing could are at risk, as well as the 3pm Manannan service to Liverpool and the sailing back to Douglas at 7.15pm.
The Isle of Man Constabulary has also issued an alert for Friday and Saturday, when spells of heavy rain are forecast.
Officers warn localised flooding is possible, especially where drains are blocked by leaves or debris.
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