Rox said its "highly sophisticated" new smoke cloud system released a heavy fog which reduced visibility when activated.

BBC: Rox in George Street in Edinburgh

We landed in Frankfurt in heavy fog and gathered in the terminal for the first time as a full group.

NEWYORKER: The Grand Tour

The accidents began shortly after 13:00 local time (17:00 GMT) on Sunday, when there was heavy fog in the area.

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Two days later, India said Pakistani soldiers, taking advantage of heavy fog, crossed the de facto border and killed two Indian soldiers, beheading one.

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Such minimally conscious patients, while bedridden and in a heavy fog, can sometimes answer a yes or no question, follow simple commands or utter a few words.

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The Coast Guard is being criticized for waiting hours before telling the public the spill was much worse than originally reported, and the Coast Guard's Rear Admiral Craig Bone says that heavy fog is no excuse for running into the bridge.

NPR: San Francisco Bay Oil Spill Investigated

Organisers feared the event would have to be cancelled because of heavy rain and fog, but the 160 competitors carried on.

BBC: Charity bikers defeat weather

Designed to operate in fog, heavy weather conditions and 5ft (1.5m) waves, the launch has a sprint speed of 20 knots (23mph) and includes a depth sounder and radar.

BBC: Breydon Water: Broads Authority launches new patrol boat

These assurances, coupled with a stronger social safety net and employment provisions (see article), may help lift some of the deflationary fog that has lain heavy over Japan for so long.

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So when there are heavy winds you often end up walking through a swirling fog of candy wrappers and cigarette butts.

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