Both Severn bridges are likely to close tomorrow due to Storm Eunice, police have said.
Stretches of the M5 motorway are also likely to be shut due to dangerous conditions around the Bristol Channel.
National Highways has advised of "exceptional sidewinds" with the power to blow over caravans and motorbikes. You can read latest updates on Storm Eunice here.
READ MORE: Storm Eunice: Met Office issues red weather warning for parts of Wales as 100mph winds to hit
The M48 'old' Severn Bridge closed overnight, but it is rare for the main bridge, controversially renamed the Prince of Wales Bridge last year, to shut.
At 6.20am on Friday, February 18, the Twitter account that gives updates on the bridges, @2SevernBridges, said: "The Prince of Wales Bridge #M4 is OPEN at this time. Please monitor feed and news for updates. We are monitoring speeds and gusts closely. Please only travel if essential."
Avon and Somerset Police have said there is a 'high likelihood' both bridges will be closed. And National Highways, which manages roads in England, has warned motorists to prepare 'for the worst case scenario as there is a very high risk' both bridges will close. Police are asking drivers to avoid non-essential travel.
The Avon and Somerset Resillience Forum added: "There is also a risk of 90mph gusts of wind causing coastal flooding and affecting trees and temporary structures.
"This could cause disruption to the road and rail network, flights, power and communications systems with a high likelihood that both the M4 Prince of Wales bridge and the M48 Severn Bridge will be closed".
The list of roads likely to be affected:
M48 Severn Crossing
M4 Prince of Wales Bridge
M49 - M4 J22 (at Severn Crossing) to M5 J18 (at Avonmouth)
M5 J13-J15 Stroud to M4
M5 J18-J19 Avonmouth Bridge
M5 J20-J23 Clevedon to Bridgwater
Schools will close across Wales on Friday, while train services have also been suspended. You can find out more about what has been cancelled or is set to be closed here.
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