Modified glucagon peptides are disclosed having improved solubility while retaining glucagon agonist activity. The glycogen peptides have been modified by substitution of native amino acids with, and/or addition of, charged amino acids to the carboxy terminus of the peptide. The modified glucagon agonists can be further modified by pegylation, or the addition of a carboxy terminal peptide selected from the group consisting of SEQ ID NO: 20, SEQ ID NO: 21, SEQ ID NO: 23, or both to further enhance the solubility of the glucagon agonist analogs.