Highways England said the delays are on the M6 northbound between junction 27 (Shevington Interchange) and 31 (Samlesbury Interchange) this afternoon (May 31).
70 minutes delays have been reported in the area due to heavy congestion.
Traffic jams have also been causing "40-minute delays" on the M61 northbound to junction 8 (Chorley North Link Interchange).
A spokesman for Highways England said: "There are currently severe delays on the M6 northbound between J27 (Shevington Moor) and J31 (near Preston) in Lancashire.
"This is due to the volume of traffic currently heading to the North West region.
"There are currently 70-minute delays above normal travel times with 11.5 miles of slow-moving traffic on approach to J31.
"There are also 40-minute delays on the M61 northbound with seven miles of slow-moving traffic on approach to the M6 link back past J8."
Road users intending on using the M6 or M61 have been encouraged to allow plenty of extra time for their journey.
More to follow...
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