UPDATE (6:59 a.m.): All lanes of northbound 99 are back open. Big rig is cleared.
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All northbound lanes of the 99 at Stockdale Highway are blocked after a big rig jack knifed Friday morning.
According to the CHP, the big rig jack knifed at about 5:45 a.m. just near the off ramp.
No injuries have been reported.