The gale force winds could lead to damage and cause disruption to transport networks, the warning states.
Forecaster are predicting that both Wednesday and Thursday will be very unsettled, with strong winds combined with heavy rain.
Met Office spokesman Richard Miles said: "We can expect gusts of 60mph and in the most exposed westerly places along the western coast from Cornwall to the Shetland Islands could see gusts of up to 70mph".
Heavy winds are expected tomorrow..
United States judge delays ruling on 'interesting' Julian Assange case
Months later WikiLeaks released a stash of Democratic emails stolen by Russian intelligence officers. A well-placed source has told the Guardian that Manafort went to see Assange around March 2016.
The Met Office has issued yellow weather warnings for western parts of the country as the powerful winds approach.
Although mild, it will become very windy everywhere, with gales or severe gales affecting much of the north and west. Rain is likely everywhere, heaviest over Scotland and Northern Ireland.
High seas are also expected, with a risk of coastal flooding.
Mourinho: Face the pressure or stay at home
Get out while you can, men. "I want them to start strong and have a go nearly immediately". I want to play like a knockout game .
Oldhamers are being warned today (Wednesday) to brace themselves for the arrival of Storm Diana, which is due to hit the borough tomorrow.
It is threatening the Azores at present and is due to make itself felt over western parts of the United Kingdom from tomorrow.
"There remains a small chance that this system will intensify as it moves northeastwards bringing even stronger winds to southwest England, Wales and on into northern England and southeast Scotland". If you have travel plans, through the rush hour for example, there could well be some issues. Here's how:Conditions are expected to turn wet and windy from Tuesday afternoon, with the storm officially arriving on Wednesday.
Lewis Hamilton clinches victory in Abu Dhabi to crown season
"The whole situation was under control and the doctor was happy with the process", he added. "I wanted to finish on a high". When asked if Alonso could test the 2019 auto , Brown said: "Yeah, I wouldn't rule that out".