Previous works have demonstrated the ability of solar energetic particles to affect mesospheric electric fields. In this work, we suggest that such particles can also affect the fair-weather electric field at ground level. Our model applies previously derived changes in the high-altitude atmospheric conductivity profile to the global electric circuit. We find that the strongest flare-generated proton events are capable of creating a measurable change to the electric field at ground level (~5% change), but these changes are small in comparison to those associated with passing thunderstorms.