The current El Nino continues to grow. The Oceanic Nino Index was 1.0 at the end of July, making it a moderate event. At the end of August it was reported to be 1.2, increasing but still moderate. But, the monthly diagnostic report released September 10 stated it is currently at 2.0. This is not only a major increase, it makes this a strong El Nino (the ONI threshold for 'strong' is +1.5). And, it is still getting stronger. It is already one of the three strongest El Nino's ever recorded. The ENSO team gave a 95% chance it will continue through the northern winter and gradually weakening through the spring.
This is significant and we can expect to see some major weather events associated with this. One of the forecasts is for more rain across southern California and the Southwest U.S. While we all want to see the drought end in California, this will likely do more harm than good. One year of above average rain will not relieve the drought. If the rain comes in torrents it will cause flooding and mudslides and then runoff into the ocean. What California needs is large snowpacks, but with the warming climate, less and less of the precipitation is coming as snow. What use to be snow a few years ago is now routinely rain.
Additional impacts for the U.S. include major winter storms for the northeast. Brace yourself for more ignorant comments about 'where's the global warming?' Another effect is to kill hurricanes in the Atlantic. High level winds chop off the top of tropical cyclones and prevent from getting stronger. We have already seen exactly this happen to several storms in the Atlantic this season.
The good news is while we are not very good at predicting when an El Nino event will occur, once they do happen, we're good at predicting the effects.
Keep an eye open for long-range forecasts resulting from this event.