75,000 without power after 100 mph storms hit north and west Wales
Some 75,000 homes are still without power as winds of over 100 mph batter the coast forcing the closure of roads, rail lines and schools.
Wales has been offered military help following Wednesday's storms.
Secretary of State David Jones spoke to First Minister Carwyn Jones after the UK government's emergency Cobra meeting and offered the Army's help.
A red "take action" weather warning was issued by the Met Office as exceptionally strong winds hit.
The west and north west coast have been worst hit, and a gust of 108 mph has been recorded at Aberdaron, according to the Met Office.
Scottish Power said 52,000 homes were without power in mid and north Wales, while Western Power Distribution (WPD) had 23,000 homes affected in south and west Wales.
At its peak on Wednesday evening there were 90,000 homes affected.
Phil Davies, network services manager for WPD, said: "We've got staff out there. We were prepared for it.
"We came in first thing this morning, and stopped all planned work, but it's difficult, some of our guys can't get out of their vehicles let alone get up a pole to fix it.
"But we're bringing in guys from other areas. We'll be out all night and first thing in the morning, trying to get people back on, but it is difficult."
A Wales Office spokesman said talks between the Welsh secretary and first minister have taken place over the weather situation.
He added: "He told the first minister that, if required, he just needs to ask for military assistance.
"Obviously the kind of assistance will depend on what was needed.
"However, the secretary of state, having attended Cobra this morning, said he would work with cabinet colleagues to make resources available."
In Cardiff, a man was left injured on Westgate Street after he was apparently struck by a street sign blown over in the wind.
And Rhydhelig Avenue, one of the main routes used to get to the University of Wales Hospital - including by ambulances - was blocked by a fallen tree but has since been cleared.
North Wales Police, Dyfed-Powys Police and Mid and West Wales fire service all urged people to stay indoors during the high winds with conditions described as "treacherous".
Part of Mold Road in Wrexham has been closed until Thursday morning after damage to part of the roof of the Racecourse football ground. This is expected to cause traffic problems.
On Anglesey, eyewitnesses saw wind turbines on fire near Cemaes.
Simon Williams, who lives near the site, said: "We live just down the road and looked out of the window and all you could see was this wind turbine with flames behind it.
"We saw two of them on fire. It was quite a sight."
Mr Williams said the two turbines, which he estimated are about a mile apart, were on fire for about an hour.
In Ceredigion, Aberystwyth University advised staff and students to leave the campus as soon as they could while most bus services in the county are suspended.
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All rail services west of Llanelli have been suspended, as have services between Bangor and Holyhead.
But the weather warning is expected to be downgraded to a yellow "be aware" warning on Thursday.
BBC Wales weather presenter Behnaz Akhgar said: "It will be much quieter on Thursday, with a risk of icy patches first thing. It will still be breezy but much lighter winds compared with today. There will be some sunny spells with heavy showers which could have a wintry element.
"Then all eyes will be on the next area of low pressure which will bring more wind and rain with it through Friday. There will be very unwelcome rain with further risk of flooding. But the rain will clear north-eastwards on Saturday leaving a mostly dry day on Sunday."
Ceredigion, Gwynedd, Anglesey, Pembrokeshire, Conwy, Powys areas have all been badly affected.
Dyfed-Powys Police and North Wales Police have been holding emergency meetings with other agencies to discuss the storm, which has been causing severe damage in parts of Wales.
On A487 near Penycwm, Pembrokeshire, the force of the wind blew a door off a bus, but no one was injured.
Roof panels have come off Sir Thomas Picton school sports hall in Haverfordwest, which will be closed on Thursday as a result, while Spittal school, also in the town, has slates come off the roof.
And a school bus has been hit by a tree but no children were on board.
Meanwhile in Carmarthenshire, Pembrey and Llyn Llech Owain Country Parks were closed because of a risk with falling trees. Abergwili Museum and Parc Howard Museum were also closed.
St Fagans National History Museum on the outskirts of Cardiff was also shut for health and safety reasons due to the weather.
The strong gusts caused disruption in west Wales with roads closed due to fallen trees, and more than 70 schools closed across the country.
"Safeguarding is a priority," said Janet Kingston, head teacher of Greenhill School, Tenby.
"We have checked the winds and they are around 70 mph at present, and the coastguard and the Met Office have warned us they are likely to peak at 3pm when pupils leave," she said.
"Flying debris could be a danger. There is nothing spectacular but because the winds are due to get to hurricane force we have brought the departure time forward."
Some residents in Criccieth, Gwynedd, told BBC News the wind and rain had been relentless.
"I've never seen anything like this before. Since Christmas, there hasn't been a day which hasn't seen strong winds or rain," said Dei Jones.
"I do a lot of walking, and you'd have to be at 3,000ft to get weather like this. It does seem endless."
The strong winds have also been battering the Aberystwyth coast.
"Winds are incredibly strong up here and the rain is battering down," said BBC Wales' Charlotte Dubenskij who is in Llandre in Ceredigion, west Wales.
The severe weather has caused severe disruption on the roads, with the Cleddau Bridge in Pembrokeshire and the M48 Severn Bridge being closed to all vehicles.
The M4 at the Briton Ferry Bridge between junctions 41 and 42 for Baglan and Fabian Way has re-opened after being closed because of strong winds, while one lane on the M4 westbound between junctions 47 and 48 was closed by a fallen tree.
The Britannia Bridge, which connects Anglesey to the mainland, has closed because of an overturned lorry and a man has been arrested has on suspicion of dangerous driving.
As well as road chaos, ferry services from west Wales are cancelled and there is a revised timetable for train services due to flooding.
Arriva Trains Wales passengers have been told to check before they travel as all services are facing delays.
Meanwhile, Natural Resources Wales has six flood warnings in place.
Carmarthenshire council will have gritters out later on main routes as temperatures are expected to dip below freezing.
The Welsh government said it was monitoring the situation.
A spokesperson said: "We would advise those in affected areas to take care, to only make journeys that are essential and to prepare properly when doing so."