nb-si-nadinecaisselong

Nadine Caissie-Long, a River Watch data specialist, says a slow snow melt helps prevent flooding. (CBC)

A forecast of above-freezing temperatures and heavy rain has prompted New Brunswick's River Watch to issue a flood advisory.

The weather conditions are favourable to promote the deterioration of ice covers, particularly in the southwestern part of the province and Bay of Fundy coast, a statement issued late Tuesday afternoon states.

"This could lead to movement and break-up of ice covers in these areas and the possibility of ice jam flooding," it says.

Environment Canada has also issued a special weather statement for St. Stephen and northern Charlotte County, Grand Manan and coastal Charlotte County, Saint John, St. John County and Fundy National Park, which are expected to get 30 to 40 millimetres of rain, starting Tuesday night and ending late Wednesday.

Rainfall may cause localized flooding in other areas where drainage systems are blocked by ice and snow, River Watch advises.

People living or working along streams, tributaries and rivers are asked to keep a close eye on ice movement and the possibility of ice jam formation, resulting in water level increases.

They should avoid ice crossings with recreational vehicles and take precautions to protect their homes and possessions, such as elevating or removing items from basements, the group says.

Overall calm season expected

Still, Nadine Caissie-Long, a River Watch data specialist in Fredericton, said there are some positive indications this year's flood season will be a quiet one.

The snow pack is down significantly across the province and temperatures have been above normal during the day and just below the freezing mark at night.

"That type of weather is actually really good weather to have a slow melt which is really what we like to see. So it gives the time for the river to collect the water and slowly bring it down." said Caissie-Long.

Forecasters can predict open-water flooding 48 hours in advance, she said.

But as the community of Perth-Andover found out last year, ice-jam floods are much harder to predict. That community faced what some residents called the worst flooding in a quarter of a century.

"It's very, very hard to forecast ice jams because every ice jam is actually unique," said Caissie-Long.

Environment Canada Meteorologist Claude Côté said the forecast this spring looks promising.

"There's a pretty good indication that the temperature regime will be above normal, but as far as precipitation amounts are concerned, it's very much up in the air and very dependent on the specific track of weather systems," said Cote.

Caissie-Long suggests everyone who has experienced flooding in their home be prepared, just in case.

"Making sure their valuables in the basement are put up as well to just be vigilant and watching the weather forecasts and also looking at our river forecasts," she said.

River Watch is a partnership of the Department of Public Safety, with federal, provincial and state agencies involved in monitoring and flow forecasting for the St. John River basin.