* WCS quoted at $29.50/bbl under WTI
* Light synthetic quoted at $6.25/bbl under WTI
* Tight pipeline space, refinery outage are big factors
CALGARY, Alberta, Nov 5 (Reuters) - Canadian cash crude oil prices rose on Monday from last week's seven-month lows, but remained weakened by the effects of an unexpected pipeline shutdown and a lengthy outage at BP Plc's big Whiting refinery in Indiana, market sources said.
Western Canada Select heavy blend for December delivery was last quoted at $29.50 a barrel under benchmark West Texas Intermediate, up $2.15 a barrel from Friday's settle, according to Shorcan Energy Brokers.
December light synthetic, derived from the Alberta oil sands, fetched $6.25 a barrel under WTI, up $2.75 a barrel.
Traders did not view the improvement as a fundamental turnaround in a market that has weakened steadily over the past month.
"(There are) lots of barrels out there in November without a home," one market source said.
Last month, TransCanada Corp took its 590,000 barrel per day Keystone oil pipeline down for an unplanned five-day outage so it could investigate what it termed as a "small anomoly" detected on a section of the pipe.
When it restarted the line, the company said it would not be able to deliver all of the scheduled October volumes, and would work with its shippers to determine how to deal with the backed-up crude.
Meanwhile, Enbridge Inc rationed space for this month on five U.S. Midwest pipelines after nominations exceeded available space.
At the 337,000 bpd Whiting refinery, a big buyer of Canadian crude, BP started major maintenance that is expected to reduce output by about half until around the middle of next year.
The work is part of a $4 billion upgrade that will allow the refinery to process more Canadian heavy crude.