Aviation Flight Categories (AFC)
Category Ceiling Visibility Symbol
LIFR* below 500 feet and/or less than 1 mile LIFR symbol
IFR 500 to below 1,000 feet and/or 1 to less than 3 miles IFR symbol
MVFR 1,000 to 3,000 feet and/or 3 to 5 miles MVFR symbol
VFR** greater than 3,000 feet and greater than 5 miles  

* By definition, IFR is ceiling less than 1,000 feet and/or visibility less than 3 miles, LIFR is a sub-category of IFR (ceiling less than 500 feet and/or visibility less than 1 mile). The Aviation Weather Center distinguishes LIFR from IFR for the purposes of this graphic.

** By definition, VFR is ceiling greater than or equal to 1,000 feet and visibility greater than or equal to 3 miles, MVFR is a sub-category of VFR (ceiling 1,000 - 3,000 feet and/or visibility 3 to 5 miles). The Aviation Weather Center distinguishes MVFR from VFR for the purposes of this graphic.