Light snow is expected to spread across the Upper Mississippi Valley and Great Lakes region on Tuesday morning, affecting areas along the northern edge of a precipitation shield. While accumulations are predicted to be modest, the light snow may reduce visibility and create slippery road conditions, potentially impacting morning commutes. Motorists are advised to allow extra travel time and remain vigilant for changing conditions. Residents in the affected areas should stay informed by monitoring local weather advisories and adjust their activities accordingly.