A rolling road block was put in place on the M6 following a series of multi-vehicle accidents, say police.
The accidents happened on both the north and the southbound carriageways at junction 34 at around 7am this morning.
Police say that dangerous driving conditions on the stretch of motorway were caused by a sudden wintry shower.
The road reopened at around 9.30am police said.
Force Incident Manager for Lancashire Police said: "We have had a number of accidents on the motorway around junction 34 following a sudden fall of hail.
"One crash led to another. Thankfully there were no serious injuries reported.
"A rolling road block has been put in place but the road should be fully reopened shortly.
"During wintry showers drivers should exercise caution on their journeys."
North West Motorway police urged people to drive sensibly in the treacherous conditions.
Further accidents were reported on the M61 near Chorley and the A56 near Rising Bridge towards the M65.
Fire services attended one crash on the southbound M61 near to Chorley and were called back to another on the northbound carriagway as they were leaving the scene.
A spokesman said: "We attended a crash which happened on the southbound carriageway and were called back to another series of crashes on the northbound carriageway.
"In the northbound incident one car went off the road and hit a tree. A lady stopped to help the driver and another two cars skidded into the back of hers.
"Thankfully nobody was injured."
The A56 was closed earlier but reopened in both directions between A680 and the M65 at around 1.30pm.
A spokesman for North West Motorway Police said: "We cant stress enough - sensible driving people in these treacherous conditions, we have numerous vehicles on their roofs, people trapped.
"Police are trying to deal, however, this is being hindered as other vehicles are driving at speed and skidding into the back of the vehicle."