The Department of Education has said that schools and colleges should stay closed on Friday if there is a risk to safety due to the arrival of Storm Callum..
By Sunday, the weather is expected to settle down slightly as both warnings are lifted.
The UK Met Office now has a yellow wind warning for Friday and rain warning into Saturday.
Natural Resources Wales (NRW) warned that weather conditions at sea could also cause flooding with large waves, strong winds and a tidal surge.
The orange weather warning will come into force at 10pm tonight and remain in place until 12 noon tomorrow (Friday ).
The Met Office said that "leaves and twigs, brought down by the wind, could block drains and culverts, increasing the likelihood of flooding".
"Some exposed locations could see as much as four inches by the end of Friday".
There will be spells of heavy rainfall and high tides with the possibility of coastal flooding.
Winds of 50mph will batter Northern Ireland, southwest England and west Wales during Thursday night, spreading to Scotland by Friday morning.
Winds will be strongest overnight and early on Friday, gusting between 110 and 130 km/h at coasts.
Arriva Trains Wales is planning to shut the line between 7am and 11am on Friday morning and in the evening.
"The track of this storm is a bit further north than Storm Ali, so therefore Callum shouldn't be as damaging as Ali was in central parts of the country".
Winds of up to 130km are expected, possibly going even higher in coastal areas.
Speaking this morning, Met Éireann meteorologist Harm Luijkz said tonight is to become "very windy as Storm Callum arrives".
"We are advising people to avoid coastal areas during this event".
South Wales is bracing itself for a two-day deluge that's expected to cause flash floods and travel chaos.