On the second working day after the Eastern Harbour Crossing's toll hike, there were 4,900 more cross-harbour vehicles than a day earlier, the Transport Department says. Drivers of more than half the increased number - 2,700, including 400 goods vehicles - chose the Cross Harbour Tunnel.

In general, traffic flow on both sides of the harbour remained smooth up to 3pm, with 7,800 fewer vehicles than normal using the three tunnels, a fall of 6%.

Deputy Commissioner for Transport Lau Ka-keung said up to 3pm today, three was a 1% drop in the number of drivers choosing the Cross Harbour Tunnel - or about 700 fewer vehicles than normal. The Western Harbour Crossing saw an 8% rise, with about 1,800 more vehicles.

The eastern tunnel saw a 22% fall, with about 8,900 less vehicles compared to a normal working day.

After 3pm, tunnel traffic started getting busier, he said, reminding the public the horse-racing at Sha Tin tonight may cause extra traffic in the evening.

Mr Lau said the Hong Kong Observatory forecast showers tomorrow and rain on Friday. Those days are also known to experience heavier traffic.

He advised commuters to make full use of public transport and start their journey earlier, in particular students taking HKCEE English examinations on Friday.

In the last three days, 16,600 people have visited the Transport Department's website and 615 people have called the Government hotline, 1823, to get updated traffic information.

Mr Lau urged the public to make use of these channels to plan their journey and reiterated the department will remain vigilant and closely monitor the traffic situation.