Storm Austen has led to power cuts, damage and travel disruption across Anglesey and Gwynedd.
Work has been paused on refurbishing the former marine terminal buiding at Porth Amlwch after a new roof beam was damaged.
Anglesey Council has urged local residents to avoid the area while contractors make the site safe.
The former Shell terminal is being refurbished as part of a wider £10.4 regeneration scheme.
During the day, dozens of power cuts were reported across the region, including the Caernarfon, Llangefni, Amlwch and Cemaes Bay areas.
A spokesperson for SP Energy Networks said: "Our teams are on the ground, with additional resources standing by across our network areas, ready to respond to any disruption and restore power as quickly and safely as possible."
"Storm Austen will continue to bring wet and windy conditions to parts of the UK today...and Storm Boelo is expected to bring another spell of heavy rain and strong winds from Saturday."
Meanwhile, the Eryri Marathon, which was due to be held on Saturday, has been cancelled after organisers deemed the course to be unsafe.
A spokesperson said: “Though conditions have eased this evening, unfortunately the forecast for tomorrow has worsened considerably.”
”To say we are heartbroken would be an understatement, but we have to think of the safety of everyone involved, not just our runners but our incredible marshals, some of whom are out there for over eight hours.”
The A55 over Britannia Bridge remains open to all traffic although a 30mph speed limit is in place, with Traffic Wales urging motorists to allow extra time for their journeys and take extra care on the roads.
Elsewhere, level crossings are closed at Ty Croes, Valley, Llanfairpwll and Gaerwen, while the flood gates at Beaumaris have been closed due to exceptionally high spring tides.
Stena Line has also cancelled a number of its ferry crossings between Holyhead and Dublin this weekend.
A Met Office yellow warning for strong winds across most of the region expired at 5pm, although a similar warning remained in force across the rest of North Wales until 9pm.


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