Gale force winds are battering England and Wales while heavy rain threatens flooding.
The Met Office has issued weather warnings for wind across south-west England, the Midlands and the South East, and for wind and rain in Wales.
Flood warnings and alerts are in place for Wales and southern England as the weather system moves east.
Naer Tavistock in Devon, three people escaped unharmed after their car was crushed by a fallen tree.
Winds could reach 40-50mph inland, while the south Wales coast, the Bristol Channel and the south coast could see gusts of up to 60 mph, forecasters warned.
One gust of 82mph has been recorded at the Needles on the western tip of the Isle of Wight, BBC weather said.
More exposed areas could see gusts of up to 65mph with the threat of some disruption such as fallen trees.
BBC weather forecaster Laura Gilchrist said: "This weather would not be unusual in October or November, but as it's coming in June the trees are more in leaf and people are carrying out more outdoor activities than then, so there's more risk of disruption than at other times of the year."
There is also the potential for high waves as the wind funnels through the Bristol Channel.
Met Office spokesman Charlie Powell said: "It is possible there could be up to three inches of rain in hilly and mountainous areas of Wales, with lower but still substantial rainfall in more low-lying areas."
In Wales, high winds have forced the postponement of races in the Canoe Slalom World Cup in Cardiff Bay. Competitors from 38 countries were due to take part in the pre-Olympic event at the white water centre
In the south west, uprooted trees have brought down cables, leaving 300 homes without power and the Plymouth lifeboat has been sent to rescue a fishing boat near the Eddystone Rocks off Rame Head in Cornwall
In the south east, the Highways Agency has told drivers of high-sided vehicles to avoid the A2 and A20 in east Kent, the A26 between Lewes and Newhaven and the A27 from Pevensey
There is brighter news for the weekend, as the weather is set to improve for Saturday, feeling much warmer and with sunny spells.
The positioning of the jetstream [a fast-flowing air current in the upper atmosphere] is to blame for such wintry weather in June, Ms Gilchrist said.
"It should be further north. It's taken a little bit of a dip south, which is allowing weather systems to develop across the UK, but it has the potential to move back again," she said.
Uprooted trees have brought down power cables and Western Power Distribution engineers are working to restore power to nearly 300 homes across the region.
The Plymouth lifeboat has been sent to rescue a fishing boat near Eddystone Rocks off Rame Head in Cornwall.
Road closures and cancelled ferries have caused some travel problems.
Falmouth Coastguard said the French fishing vessel Maranello, with a crew of five on board, got into difficulties in rough seas after complete engine failure on Thursday night.
Another fishing boat anchored nearby overnight to keep a watch on the Maranello, but the Plymouth all-weather lifeboat was sent out at 06:15 BST to tow the vessel back to Plymouth.
Devon County Council control centre said that since the gales started to batter the South West on Thursday afternoon, its teams had cleared at least 50 fallen trees.
The Environment Agency still has a number of flood alerts on rivers and some coastal areas of the South West.
The Met Office said the gales and heavy rain should begin to gradually ease in the South West from about midday.
Falmouth Coastguard said it had been a "very busy night" with several incidents to deal with, but there had been no major rescues.
M4 south Wales The M4 in south Wales on Friday morning: wet and windy with plenty of surface spray
Large parts of Wales have been hit by summer storms, with heavy rain and 60mph gales expected to affect much of the nation.
The south and west are expected to bear the brunt of the gales, especially on the coast and on high ground.
Environment Agency Wales (EAW) has warned of flooding and damage to trees.
Early on Friday there were three flood alerts in place - the lowest category - but no flood warnings.
The alerts are for the Rhondda rivers, Llyn Peninsula and Cardigan Bay coastline.
Earlier alerts for the Wye Estuary, Usk Estuary, the coast from Aberthaw to the Severn Bridge, and Swansea Bay and the Gower coast were withdrawn, as high tides peaked on Friday morning.
Alun Williams, from Environment Agency Wales, said continuing rain throughout Friday could still pose possible coastal and surface water risks.
"The tides are due to peak at about nine o'clock [on Friday] morning, so hopefully, should the winds die down, that risk will diminish a bit," he said.
"The main risk at the moment of flooding seems to be surface water flooding on roads. Drivers should take care under these conditions."
He also urged the public not to risk watching the storm surges on the coastline.
"I think that one of the risks we do have is that this kind of event is very much a spectator event," said Mr Williams.
"Unfortunately we have had fatalities as a result of that. People don't appreciate the kind of risk and the strength of waves, and can be quite easily swept off their feet."
About 50 - 100mm of rain (2 - 4in) is possible on high ground in the south and west and parts of mid Wales by the end of Friday.
The conditions brought some trees down in the Llansamlet area of Swansea, while surface water partially blocked Queensway in Newport on Friday morning.
BBC Wales meteorologist Derek Brockway said: "This is very unusual for this time of year".
"Wales is in the firing line for some stormy weather in the next 24 to 36 hours with a deep area of low pressure moving across the UK bringing heavy rain and strong to severe gale force winds," he said.
"The south and west will bear the brunt of the gales, especially on the coast and on high ground with gusts around 60mph or more in exposed locations.
"The wind could even bring down a few trees given they are in full leaf. Poor travelling conditions are likely too with a lot of surface water and spray on the roads and motorways."
"Over the weekend, the weather will improve, turning drier and brighter with some sunshine and lighter winds. Perhaps a few showers on Sunday."
The Met Office issued two yellow alerts for severe weather affecting Wales. The first for rain covers the whole of Wales, while the second warning of high winds affects south-east and south-west Wales, extending towards Aberystwyth in Ceredigion.
However, much of northern Powys, north-west and north-east Wales currently remain unaffected by the wind warning, though it will remain wet and blustery.
The changeable and unsettled weather looks set to continue for at least the next 10 days with a mixture of sunshine, showers and longer spells of rain at times.
This post has been edited by skanky: 08 June 2012 - 09:02