SPEI value | Drought severity class |
2.0+ | Extremely wet |
1.5 to 1.99 | Very wet |
1.0 to1.49 | Moderately wet |
0.99 to − 0.99 | Normal |
−1.0 to −1.49 | moderately dry |
− 1.5 to −1.99 | Very dry |
−2.0+ | Extremely dry |