UPDATE (4:10 a.m.): According to the CHP, the driver of the big rig says he was eating while driving and his big rig drifted into the guardrail at the time of the crash this morning. 

The CHP says the driver was hauling cheese.

The CHP expects traffic in the area to be impacted until about 7 a.m.

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A big rig has rolled over on the Southbound 99 near 7th Standard Road on Tuesday morning.

According to the California Highway Patrol, the big rig overturned around 3:15 a.m. near the center divider. Initial reports indicate the big rig was carrying produce.

It's not known if there are any injuries or if any lanes are being blocked.