What does it mean for the Lord to be angry? Let us look to Jesus to define God's anger for He is the way to the Father.
When Jesus stood before the leaders of Israel and told them they were hypocrites he was certainly angry. Was the culmination of this anger?
Matt 23:37-38 O Jerusalem, Jerusalem, thou that killest the prophets, and stonest them which are sent unto thee, how often would I have gathered thy children together, even as a hen gathereth her chickens under her wings, and ye would not! (38) Behold, your house is left unto you desolate.
It causes the Lord incredible grief to finally have to allow his wayward children have their decision to reject Him. The anger of the Lord is to leave the house of the wicked desolate while experiencing terrible grief.
A common word anger in Hebrew is aph and it means rapid breathing through the nose. It can be either anger or grief or both. It depends on how you view God.
When you see the biblical meaning of anger your heart will go out to our Father in sorrow for all the suffering He has endured because of our sins. We we allow Him to gather us to him or will our house be left desolate for the serpent to come and destroy?