An air stagnation advisory originally set to expire Sunday has been extended until 10 a.m. Tuesday, the National Weather Service reports.
Because of limited air movement, a high pressure system will remain in the area, trapping pollutants and resulting in thick, freezing fog in the Rogue Valley.
"Air quality will be compromised through this weekend into Tuesday morning," a statement on the NWS advisory reads.
Area residents with respiratory ailments like asthma should use caution when doing physical activities outdoors because of the downgraded air quality.
A freezing fog advisory is in effect until noon today. The poor visibility and icy roads will mean an increased danger for motorists. Visibility is less than one-quarter mile in some areas. Drivers are advised to use their headlights, even during daylight hours, reduce their speed, and allow for additional distance between vehicles.
— Ryan Pfeil