| Color | Categories | Index values | Color | Categories | Index values |
|
| Exceptionally drought | ≤−2.326 |
| Highly wet | +0.524 to +0.935 |
|
| Extremely drought | −1.645 to −2.326 |
| Moderately wet | +0.935 to +1.282 |
|
| Severely drought | −1.282 to −1.645 |
| Considerably wet | +1.282 to +1.645 |
|
| Moderately drought | −0.935 to −1.282 |
| Extreme wet | +1.645 to +2.326 |
|
| Minor drought | −0.524 to −0.935 |
| Exceptionally wet | ≥2.326 |
|
| Near normal | +0.524 to −0.524 |
|
|
|