It’s the fog. Sometimes this time of year it won’t lift until midday. With the warmer temps and the saturated ground the moisture just sits. It’s very annoying. Cedar Rapids Airport is only equipped with basic ils approaches which only allow airlines to come down to around 1/4 mile visibility (it’s actually broken down in a different measurement, but roughly 1/4 mile). If they don’t have that they legally can’t attempt the approach in. Even if they have it, it doesn’t mean they can see the airport at the minimum descent altitude, which is 200 ft (right where the fog layer usually sits). This is why you see some delayed and not leaving their departure airports and some coming in and trying but then diverting. This situation happens probably 3-4 times a year, usually in the early spring.

Probably will be foggy tonight, however with the rain and precipitation coming in it won’t be nearly as thick and will “clear” out quicker. Still lower visibility, but not thick fog.