Storms and security fears threaten New Year revels

New Year's Eve revellers are being warned to be extra vigilant amid fears that terrorists may target London in retaliation for the execution of Saddam Hussein.

With serious concerns over whether the celebrations can go ahead after predictions of storm-force winds, Whitehall sources added to fears over the viability of many festivities by describing the security threat as remaining "real and serious", although the security services have yet to receive any "specific" new warnings.

A source said there was no need for anyone to be alarmed, but stressed that the public needed to be alert over suspicious behaviour. "We ask everyone to be alert and to contact the police anti-terrorism hotline to report any suspicious behaviour," they said.

The warnings added to pressure on organisers already fighting to save some New Year celebrations

Edinburgh's massive outdoor Hogmanay street party is among those most at risk, while Liverpool has already postponed its firework display until later in the week. Officials from Glasgow to Leeds, Newcastle-upon-Tyne to Birmingham are also anxiously checking the weather forecasts.

The Metereological Office is predicting winds gusting up to 80mph this evening, as the latest in a series of storms sweeps the country. They are expected to be at their worst in southern Scotland, northern England, north Wales, and Northern Ireland.

Julian Mayes, a forecaster with MeteoGroup UK, added: "The timing is very inconvenient for events and festivities on New Year's Eve, with lots of people hoping to be outdoors. The weather could have quite an impact on those celebrations, particularly in Scotland."

Meteorologists say that the storms, which have been caused by the jet stream - the giant, high current of air that does much to determine the weather - moving unusually far south, will be similar to the infamous 1987 "hurricane", if not nearly as intense.

Shortly to be confirmed officially as the warmest year ever in the British Isles, 2006 brought the warmest ever month (July), the hottest ever growing season, and the warmest autumn on record. Climatologists say that storms will become more frequent and more intense, as global warming raises temperatures.

Edinburgh - whose Hogmanay celebrations are thought to bring a total of £30m to the local economy - is particularly anxious about the celebrations. Three years ago the city had to cancel the festivities just an hour before they were due to start, even though the winds were far less strong than those forecast for tonight. This was at great cost to the city's reputation as a tourist destination.

Since then, the stages, on which acts headed by the Pet Shop Boys and Paolo Nutini are due to perform before more than 100,000 people, have been strengthened and the waterproofing of their electronics has been improved. A final decision on whether the celebrations can go ahead will be taken at noon today.

Glasgow - which expects some 25,000 revellers at its Hogmanay festivities in the city's George Square - says it is also keeping "a close eye" on the weather and will also make a decision today. But it is less worried than Edinburgh because, it says, the buildings around the square form a "natural barrier" against the worst of the winds.

Liverpool, however, has already postponed its firework display at St George's Plateau in the city centre - which is expected to attract 10,000 people - until Friday. The event's manager Eddy Grant said: "The safety of the public and the staff setting up the displays has to come first."

Newcastle, Birmingham and Leeds are also monitoring the weather's suitability for their festivities.