"We normally end up getting a good rain sometime along the way (to) bail us out. But this year has just been different ... the weather forecast for the next two weeks, even two months is still continued dry without prospect of rain," said Fraser.

Local hotels, restaurant and businesses complained that the closure would cause big losses, since it comes at the start of the popular three-day Labor Day weekend.

One local businessman said Tofino had regularly experienced problems with water supplies in previous years, in part because of a boom in tourism.

"Water has been a major issue in Tofino ... because of the fact that (in summer) 15,000 to 20,000 people are in a town that normally holds 1,500," Laird Salton told CBC.

The town has switched to a secondary supply and is advising residents to boil drinking water.

Fraser said Tofino planned to increase the size of its reservoir to prevent similar problems next year.

With sustained winds of 96 km/h and gusts whipping even higher, the storm is expected to make landfall on the southern Carolina coast Thursday afternoon or evening. Ernesto must have winds of 119 km/h to be bumped up to hurricane status.

A hurricane watch has been issued from South Carolina's Santee River, north of Charleston, to Cape Lookout, about halfway up North Carolina's coastline.

A hurricane watch means the region could experience hurricane-strength rain and winds within the next 12 hours.

Tropical storm warnings extend further along the coastline, from Georgia's Savannah River up to Albermarle Sound near North Carolina's northern border.

The centre is also warning of isolated tornadoes in eastern North Carolina later Thursday.

Troops on alert

Forecasters are warning people living along the Carolina coasts to expect as much as 200 mm of rain and possible localized flooding and storm surges of up to 1.5 metres.

"These amounts could cause life-threatening flash floods," the National Hurricane Centre said in its 8 a.m. ET update.

While officials haven't issued any evacuation orders, hundreds of National Guard troops are on alert, and officials in the Carolinas advised residents to be ready for anything.

"We know we're going to get a lot of rain, we know this is going to be a water event," North Carolina Gov. Mike Easley said.

According to projections, the storm could move into southern Ontario late Saturday or early Sunday.

Ernesto came ashore as a tropical storm late Tuesday in southern Florida, having lost its hurricane status after passing over the mountains of eastern Cuba.

The storm has been blamed for the death of one woman in Haiti, who was swept away by floodwaters.

Also Thursday, Mexican officials ordered the evacuation of 10,000 people as a strong Hurricane John passes by the Baja California peninsula.