By CBS13 Staff

TRUCKEE (CBS13) — Traffic is moving slow in the Sierra along eastbound Interstate 80 due to several big rig crashes Friday morning.

The eastbound side of the freeway was closed for at Farad for some time earlier in the morning due to the crashes, which have involved multiple big rigs.

Exactly what led up to the crashes is unclear, but the ground is slippery after lightning and thunderstorms rolled through Northern California overnight and brought some precipitation.

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One lane of eastbound I-80 at Farad opened around 8 a.m. Drivers are still being warned to expect heavy traffic for the time being.