Data: GFS, NOAA (resolution 22 km)
Updated: 06:00 UTC (next update: 12:00 UTC - prepare)
Current time: 18:00, 2025/04/01 (UTC)
The lifted index (LI) is the temperature difference between an air parcel when it reaches the 500 hPa level and the actual temperature of the environmental air at 500 hPa. When the value is positive, the atmosphere is stable and when the value is negative, the atmosphere is unstable. Lifted Index maps are used to forecast the likelihood of thunderstorms. Values below 0 indicating instability and an increasing chance of thunderstorms. Lifted Index is generally scaled as follows: 6 or greater: very stable conditions (without thunderstorms), between 1 and 6: stable conditions, (thunderstorms not likely), between 0 and -2: slightly unstable (thunderstorms possible), between -2 and -6 : unstable (thunderstorms likely), less than -6: very unstable (severe thunderstorms likely).