A dense fog advisory is in effect until noon today, reducing visibility to a quarter of a mile or less, according to the National Weather Service.

“Poor visibilities coupled with icy spots on the roads will increase the risk for collisions,” the advisory states.

Forecasters said the fog should start lifting by 10 a.m. Today’s high is 38.

Rain is expected to hit tonight and continue through Wednesday, when temperatures could raise into the low 40s.

An air stagnation advisory also remains in effect since pollution is being trapped near the surface, the Weather Service said.