SPI value

Drought class

Probability (%)

2 or more

Extremely wet

2.3

1.5 to 1.99

Very wet

4.4

1.0 to 1.49

Moderately wet

9.2

0.99 to 0.99

Near normal

68.2

−1.0 to −1.49

Moderately dry

9.2

−1.5 to −1.99

Severely dry

4.4

−2 or less

Extremely dry

2.3