Oct 29 (Reuters) - Next-day natural gas prices at the Sumas hub on the border between Washington state and British Columbia rose to their highest in over four years on forecasts for cooler, near normal weather in the Pacific Northwest this week following last week's above-normal temperatures.
Prices in the region have been elevated since the amount of gas flowing from British Columbia to Washington was cut to around 0.5 billion cubic feet per day (bcfd) after one of Enbridge Inc's pipes in British Columbia was damaged in an explosion on Oct. 9.
That compares with an average of 1.1 bcfd during the 30 days prior to the pipe blast. Enbridge said it expects to fix the damaged pipe in mid November.
One billion cubic feet of gas is enough to fuel about 5 million U.S. homes for a day.
Prices for Monday at the Sumas hub NG-PX-HUN-SNL rose to $9.39 per million British thermal units, according to data from SNL, their highest since February 2014.
Since the blast next-day prices at Sumas have averaged $6.22/mmBtu. That compares with an average of $2.12/mmBtu since the start of the year before the blast, $2.60 in calendar 2017 and a five-year (2013-2017) average of $3.03.
High temperatures in Seattle, the biggest city in Washington, were forecast to reach 56 degrees Fahrenheit (13 Celsius) on Monday, down from a high of 64 on Friday, according to AccuWeather. The normal high in Seattle at this time of year is 56 degrees.
Gas pipes into Washington can transport about 1.8 bcfd from British Columbia, 2.6 bcfd from Idaho and 0.8 bcfd from Oregon.
Gas pipes out of Washington can move about 0.05 bcfd to British Columbia, 0.06 bcfd to Idaho and 3.6 bcfd to Oregon.
Last winter (December 2017-February 2018) Washington consumed about 1.2 bcfd of gas on average. For calendar 2017, the state used an average of 0.9 bcfd.
Most of the gas that comes into Washington from Idaho ends up in California. That gas comes from Canada.
In British Columbia, meanwhile, the Fortis BC gas utility continued to urge customers to conserve energy due to reduced supplies from the Enbridge pipes.
Fortis BC is a unit of Canadian energy company Fortis Inc .
Reporting by Scott DiSavino Editing by Susan Thomas