Goodbye fog - hello wet and miserable

Hong Kong's fog should clear to a degree over the weekend as the relative warmth of the past few days is quickly forgotten in the face of a wet change that arrived yesterday afternoon.

Today's grey skies may well be looked back on with misty eyes compared to those expected to arrive tomorrow and on Sunday, when the city and its inhabitants will be subjected to numerous cold showers, maximum temperatures of 13 and 12 degrees Celsius respectively and cold northerly winds.

But there is a glimmer of hope on the horizon. According to the Hong Kong Observatory, Tuesday might be okay.

For while its seven-day forecast paints a gloomy picture with its 'mainly cloudy' prognosis, the optimists among the officers note that for a day to be 'mainly cloudy', it must necessarily be 'slightly sunny'.

'Things should be warming up by the middle of next week and there is a chance we will see some blue skies,' senior scientific officer Chang Wen-lam said.

But then it will get foggy again.

Mr Chang said it was quite normal for Hong Kong to experience sea fog at this time of year as warm air from the tropics moved north across cool seas.

'The sea surface temperature along the south China coast is still quite cold, around 17 to 18 degrees, but the air from the south is quite warm, at about 23 to 24 degrees,' he said.

'When this warm, humid air moves from south to north towards the coast, it cools and as it reaches dew point - today it was about 19.3 degrees - it condenses and forms the sea fog we have in Hong Kong.'

Mr Chang said the cold change this weekend was being driven by a mass of cold air associated with the tail end of the northeast monsoon, and was also quite normal.