The vehicle rolled over in the eastbound lanes to the Route 33 northbound ramp in Lower Saucon Township around 6 a.m., according to PSP Trooper Nathan Branosky.
The ramp remained open, but drivers were asked to proceed through the area with caution.
First responders were working at the scene to upright the trailer, Branosky said.
It was not immediately clear whether anyone was injured.
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