This is your Captain speaking.
The Seat Belt Sign is ON as you can see. While we are expecting a smooth flight, however, turbulence up here can NOT be forcast any better than the weather at your house can. There's always a CHANCE for it, just as there's always a chance for rain or snow at your house. There's even a CHANCE for rain in the desert.
So, unless it is absolutely necessary for you to leave your seat, I would like you to remain seated with your seatbelt FASTENED.....PLEASE. Neither I nor this airline can be held responsible if you are injured because of unforecasted turbulence, if your seat belt is not fastened with you in it.
Thank you.
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As to the remark made by 'bossan'....."How to avoid heavy turbulence ? Simple; improve the instruments which can detect it. How to achieve this ?( and I truly hate to say this) Sue and ligitate airlines and plane manufacturers until they realise that it is cheaper to develop better detecting equipment."
That seems to be the attitude of many people for many things.....sue. There ARE efforts underway to achive this very thing (forcasting turbulence). Even then, there will be encounters. You simply cannot have a 100% safe flight, much as everyone, especially the front-end crew, would like. Some people even want parachutes on board commercial flights. My suggestion to those that are worried so much.....DON'T FLY.