Forecasters are predicting further freezing downpours on Saturday, December 22 and Sunday, December 23 after floods brought parts of the county to a standstill yesterday (December 21).
Worried business leaders are concerned the dismal forecast on the busiest Christmas shopping day of the year could be a “complete disaster”.
Transport experts said flooded roads could cause traffic chaos as thousands of people take to their cars for the festive getaway.
The Met Office has issued a severe weather warning for heavy rain to fall from early on Saturday morning to Sunday lunchtime.
A spokesman warned there was a “substantial risk” of more flooding with up to 30mm of rainfall expected with strong winds gusting up to 40mph.
More bad news came from the Environment Agency, who issued a series of warnings as rivers across the county swelled towards record levels.
As well as posing a flood risk to homes and businesses, the miserable weather is also expected to keep shoppers off the streets.
Blow to trade
Tony Mernagh, chief executive of the Brighton and Hove Economic Partnership, said the predicted washout was a “real blow” to city traders.
He added: “It’s a disaster really. In these tough times you don’t want to give people any excuse not to spend money.
“The only saving grace might be that if people have left it this late, they’ll probably have to go out whatever the weather.
“But if it is raining hard, people are likely to stay in covered malls rather than going to independent retailers. It’s very worrying.”
David Sewell, chair of the North Laine Traders Association, agreed it was “a nightmare” for struggling shops.
He said: “I’ve spoken to people who say footfall is already down on last year, so this just makes things worse.
“It’s especially bad for us because everyone will just go to Churchill Square to buy their presents in the dry.”
The torrential downpours are also expected to cause traffic chaos as drivers try to negotiate flooded roads.
A spokesman for the AA said journeys could be delayed for “up to five hours” and advised drivers to be careful.
After another weaker band of rain sweeps through Sussex on Monday (December 24), Christmas Day and Boxing Day are expected to be windy but dry.
Yesterday, emergency crews spent hours battling rising floodwaters as drivers struggled through swamped roads and schools were closed.
The Environment Agency issued four flood warnings for rivers in Bosham, Emsworth, Isfield and Hellingly, urging homeowners to protect their properties.
In Eastbourne, high winds and non-stop rain caused the roof of the Langney Shopping Centre to cave in during the early hours of this morning.
Timber, metal and glass came crashing down, leaving a gaping ten metre hole.
Luckily, no-one was in the building at the time and no-one was injured.
The incident happened above the square in the shopping centre, just outside the Windmill Restaurant.
Yesterday morning, the area around the shopping centre was off-limits as building inspectors and shop management surveyed the damage.
The building must now undergo an assessment and is unlikely to reopen before Christmas.
Heavy rainfall flooded a sports pitch near Chichester Close, in Peacehaven.
Crews from East Sussex Fire and Rescue brought heavy duty equipment and pumped the pitch to stop water flooding into nearby homes.
A spokeswoman said the field was “like a swimming pool”.
Torrential rain also forced the closure of the southbound A23 near Handcross when a section of the tarmac collapsed.
Many other roads across the county were shut for long periods while crews battled to pump floodwaters away. Drivers suffered severe delays on the A27 at Middle Farm following an accident.
A spokeswoman for the Highways Agency said: “Our roads are built with drainage in mind and are designed to cope with heavy rainfall, but the amount of water any drainage system can take is finite, particularly along the A27 in Sussex for example where we have a combined high water table and a low-lying flood plain.
“The amount of rain that has fallen recently has been exceptional, and we worked hard with our contractors to clear incidents as quickly and safely as possible.”
In Emsworth near Chichester, muddy water flooded several bungalows and was two feet high in some places.
Firefighters were called to Selangor Avenue at 3.30am after the flood flowed down a field backing on to the A27 and gushed into people’s homes.
As dawn broke, residents began to pump the water out themselves but fire crews said at least two of the properties were ruined.
In nearby Bosham, Environment Agency officials warned the swollen river was expected to burst its banks near the Mill Stream Hotel.
Flooding also caused diversions and delays across Mid Sussex after a night of almost continuous rain.
Low-lying fields were under water across the district and traffic stacked up on roads swamped with surface water.
In Ifield, water levels in Ifield Brook swelled towards record levels. At 12pm the torrent reached a depth of 2.43 metres, just 12 cm off the highest level ever recorded.
Flood alerts were also issued for Upper River Mole, Gatwick Stream and Burstow Stream.
The weather also forced schools across the county to cancel classes for the day.
Twineham School, near Burgess Hill, was closed after youngsters, parents, and staff were unable to reach the gates because of a huge puddle in Twineham Lane, caused by heavy overnight rain.
Keep up to date with the latest information from the Environment Agency website http://www.environment-agency.gov.uk/flood Sign up to free flood warnings by calling the Environment Agency Flood Line on 0845 988 1188, check your route for disruption before travelling and not to drive or walk through floodwater.
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