Athletes at the Norwich Triathlon could face a tough challenge tomorrow if the forecast for torrential downpours turns out to be right.Organisers vow the race will go ahead whatever the weather and say crowds watching the event at Whitlingham Lake can look forward to seeing some top competitors toughing it out over the swim, bike and run.

Athletes at the Norwich Triathlon could face a tough challenge tomorrow if the forecast for torrential downpours turns out to be right.

Organisers vow the race will go ahead whatever the weather and say crowds watching the event at Whitlingham Lake can look forward to seeing some top competitors toughing it out over the swim, bike and run.

Heavy rain could impact on the bike phase, which takes the triathletes out through Stoke Holy Cross, to Woodton, Brooke and back through Poringland, but is unlikely to affect the swim or run legs.

The event, organised by city-based triathlon group Tri-Anglia, is an Olympic distance race which means competitiors will swim 1,500m (0.93miles), bike 40km (24.8miles) and run 10km (6.2miles).

Tri-Anglia is hoping its athletes will get home in the top places this year after the club's Jo Skipper missed out on taking the top men's spot last year when he was disqualified after failing to put his foot down on the tarmac at a junction on the bike route.

He finished in a time of 2hrs 5mins. A similar time expected for the winning man this year - the first women should come home in a time of 2hrs 20mins.

Tri-Anglia course designer Simon Edye, 55 and a veteran of six ironman competitions, said: "The race will still go ahead even if it's raining, the only problem might be if there's lightning over the lake because there is a risk of electrocution if you get a strike on the water but that would only delay the swim start.

"If we do get monsoon conditions during the bike leg then it could slow people down and if there's a lot of water on the roads then people are going to have to take more care.

"For the past two years everybody has been slowed down by the heat because it is impossible to perform at the top of your ability in 30C heat so it might be that the cooler weather this year will mean a faster race."

An impressive 284 competitors will line up at the start this year for the third Norwich Triathlon. The club is hoping to grow the entry to 2,000 to put it firmly on the East Anglia sporting map and on a par with some of the country's top triathlons, including Windsor and London.

The first competitors will set off from the Outdoor Activities Centre at Whitlingham Lake at 8am tomorrow. Spectators are welcome and should follow signs for the spectators' car park.

n For further information about Tri-Anglia log on to www.tri-anglia.co.uk. See the Eastern Daily Press next week for the race results.