Is God cleansing the earth with these recent storms? If so, is it because of divorce and the return of the Nephilim?
While the Bible discloses that God has used storms in the past to accomplish His will, the Bible warns man not to try and second guess God. ""For My thoughts are not your thoughts, nor are your ways My ways," says the LORD. "For as the heavens are higher than the earth, so are My ways higher than your ways, and My thoughts than your thoughts"" (Isaiah 55:8-9). The only way we would know for certain if there was a purpose behind the storms is for God to tell us. "For what man knows the things of a man except the spirit of the man which is in him? Even so no one knows the things of God except the Spirit of God" (I Corinthians 2:11). As we mentioned in a previous answer, God has chosen to remain silent for this period of earth's history.
Does that mean God accepts our wide spread divorce rates? Of course not! We don't need storms to tell us that; we can read it in God's word. ""For the LORD God of Israel says that He hates divorce, for it covers one's garment with violence," says the LORD of hosts. "Therefore take heed to your spirit, that you do not deal treacherously."" (Malachi 2:16). But let us assume just for a moment that it is possible that the storms are due to divorce? Why would the storms strike this particular region of the country? Its divorce rate is not that much different from other areas of the country. And how are these storms going to make an impact on the country's divorce rate? If these storms serve as a warning in regards to a particular sin, then we have a problem -- a warning doesn't work well if we don't know what we are being warned about.
God also tells us "for He makes His sun rise on the evil and on the good, and sends rain on the just and on the unjust" (Matthew 5:45). Weather events happen to both good and bad people. You can't tell a person's spiritual condition by the climate he is currently living within.
The Nephilim are mentioned in Genesis 6:4 as living in the world prior to the flood. The word in Hebrew means "giants" not necessarily in stature, but mighty men with a negative sense. In other words bullies and tyrants. It is defined within the verse when it mentions that they were might men and men of renown. Some attribute this to angels interbreeding with men, but if you read the verse carefully you will find that these giants were in the world prior to the sons of God marrying the daughters of men. The phrase "sons of God marrying the daughters of men" is simply stating that righteous people were marrying unrighteous people leading to fewer and fewer righteous people in the world.
There is no mention in the Bible of a race of people called the Nephilim returning to the world. Hence, it cannot be a cause of the storms.