Sometimes it depends on how the rain clouds form, like if there are more mountains in a certain area it might mean more rain Sorry if I'm not that helpful!
Freezing rain is composed of super-cooled water which freezes on contact with any freezing surface, forming glaze ice.Ordinary rain has a temperature above freezing and will not instantly turn to ice.
In order to have either of those, you need air, with some moisture in it. That lets the moon out on both counts ... it has no air, and any water it has is permanently frozen on or under the ground at...
Only if the rain reduces visibility below a certain level which may vary depending on which country you are in, or if there is strong crosswinds, best to check with your airlines first before...