Omens are somewhat different from signs in that they are an occurrence or phenomenon believed to portend a future event according to Webster's dictionary. As you can see, an omen is more specific. It usually entails a difficulty forthcoming in someone's life or the situation in the country where they live. Omens usually mention a dire warning "if" there is to be this occurrence. An omen isn't an accurate forecast of either a good or bad event; it is a warning "if". It should be heeded, of course, as they are not sent without a reason. It mainly comes from the Holy Spirit Energy, however, there are those who are capable of sensing a different energy there as well, and that is of the Yang Force Energy which is the Holy Father vibration. You see, if there is a strong sensing of Earth changes, for example, then there would be the Yang Force Energy present. Then of course, there would also be a type of energy saying that "if there is no change then there will be this happening occur." Omens do tend to make people nervous, as they are strictly out of the energy of the Holy One, therefore an omen sign should be watched for and not ignored.
Good omens do tend to show up as a type of guide's way of making sure you notice the good time or event coming. With omens there shows with it a type of location, as well, if there is to be this portent of future event known. Watching for a sign about where this will take place also makes it helpful, which is basically saying to just try to make sure you notice all the messages that come out of an omen. There might by a symbolic showing or a clear-meaning message given with an omen. Disaster has resulted when there is no one noticing the omen.
Going back a ways in history there were many well-known omens surrounding Julius Caesars' quest for power. Soothsayers at the time noticed several negative omens it is said and Julius Caesar was informed. History recounts that his wife, Calpurnia, had nightmares prior to the Ides of March (March 15th) the date in which Caesar was murdered. He learned of all these omens and warnings prior to his going to the senate that day, and yet he refused to heed them. It is even stated that someone had handed him a note as he was ascending the steps to the Senate forum that there was a plot to murder him, yet he didn't unscroll it, planning to read the petitions that were handed him after the Senate meeting.
Another well-known omen-sign shown to Abraham Lincoln was the event during his first term of office of his witnessing in his full-length mirror another image of himself in a pale ghostly gray appearance, making it clear to him that he would not survive his second term of office.
People in ancient times noticed all different types of weather-related omens and prepared accordingly. Any bizarre or strange oddity always got someone's attention and it would cause many to gather around to discuss what it could mean. If the meaning wasn't readily understood, then soothsayers, seers, prophets, or shamans would be sought out to decipher the meaning. Often animals would act skittish just prior to an earthquake. We now know that animals are capable of hearing extra-low frequency vibrations deep within the Earth's crust. But people have always noticed that the animals behave in this way prior to an earthquake, so they would state that if their animals were acting strange, then it was an omen of something wrong, and usually that was the case.
In researching the Bible for the ancient signs of God, I literally read more passages than I could list here of signs that God showed the people. Of course we all know about many of the more famous signs that God created when Moses was chosen by God to free the Hebrews out of Egypt's bondage in the book of Exodus. When Jesus passed into Spirit on the cross, right at that moment an earthquake occurred there, plus the tapestry in the temple of Jerusalem was torn in half all by itself. (Mt.27:51-53)
Omens do have a wonderful way of aiding those down here on Earth. They are not "hogwash" and shouldn't be dismissed when an obvious omen occurs in your life. Understand that it all comes directly from the Lord and not to consider it unworthy of your attention. If the term "omen" disturbs you, then just replacing that word with the phrase "warning from God" and you will realize that always has God been involved in our progress and these showings of signs will be there for the watchful. In the bible is is mentioned by Jesus "he who has ears to hear, let him hear". This phrase was said by the Lord Jesus and it is listed eight times in the New Testament. (Mt.11:15, Mt.13:9,Mt.13:43, Mk.4:9,Mk.4:23,Mk.7:16,Lu.8:8, Lu.14:35) So you can sense that it is indeed important to use what God wishes us to use in order to make better our way of life down here. In the Book of Hebrews 2:4 it is said: "God also bore witness by signs and wonders and various miracles and by gifts of the Holy Spirit distributed according to his own will."
It is clear that God has been displaying signs and omens for us for a very long time as a direct communication to aid our journey down here. Heeding the signs are our way of showing that we appreciate His input and help and when we receive such a sign, and to give thanks.