From: Spatio-temporal variability and trends of hydroclimatic variables at Zarima Sub-Basin North Western Ethiopia
SAI Value
Category
2 + 
Extremely wet
1.5 to 1.99
Very Wet
1 to 1.49
Moderately wet
− 0.99 to 0.99
Near normal
− 1.49 to − 1
Moderately dry
− 1.99 to− 1.5
Severely dry
− 2 and less
Extremely dry