After doing some more research.. There hasn't been much correlation between this year's ENSO phase and other years. I've been looking for years that correlated well with an ENSO neutral event after a "double dip" La Nina. So far, 1977-1978, and 2009-2010 come up.. There haven't been any other "double dippers" (I have not included the years from 1998-2001 because that wasn't really a double dip La Nina, more of a continuous one that got us going in the so far downward trend in the PDO) than these.. And I want to opt out and not include 2009-2010 because of the strength of the El Nino (at this point it isn't likely we see a strong El Nino). In fact, most of the atmospheric signals indicate that this El Nino won't even survive for the beginning of the winter. An ENSO neutral winter occurring after a double dip La Nina has not occurred in the history of record keeping of the ENSO phase. At this point, if weather patterns were to be followed, then I would predict a moderate or strong El Nino by winter. If I were to follow other signals, then an neutral ENSO winter would be more likely. I have made a map that shows the average temperature anomaly of all the ENSO neutral winters that are on record.
This clearly indicates that most ENSO neutral winters featured below normal temperatures, especially across the Northern Plains.
At this point, I really don't want to say what this winter will bring. With its unique weather patterns and variables, I cannot accurately use analogues to predict the winter temperature, snowfall, or precipitation. At this point, I'm going to lean on the side of caution. Quite a bit of data would suggest that a colder than normal winter is coming for the U.S. Some data would suggest that we will receive a warmer winter. In the history records, there have been two years that came out of a true double dip La Nina into an ENSO neutral or weak El Nino year, and one year that came out of an elongated La Nina. The two years that became a weak El Nino after the "double dip" La Nina were extremely cold years. The year that became a weak La Nina winter after the elongated La Nina, featured warmer temperatures across the East and cooler conditions in the West. At this point, the weather patterns are most similar to that of the first set of years, which occurred after a "double dip" La Nina. This would indicate that this upcoming winter could feature the same. More data will have to come up to prove this, but it is a very possible scenario. The only reason that I won't confidently project the idea of a very cold winter is because of what happened last year. For a few weeks I will wait and see what will happen.
For some entertainment, here is a map providing the average temperature anomaly across the United States from the winters of 1977-1978 and 1976-1977..
Temperatures during those two winters averaged nearly 10 degrees below normal.. According to archives and other records, the two winters featured extreme arctic cold, and several notable blizzards and snowstorms.
This clearly indicates that most ENSO neutral winters featured below normal temperatures, especially across the Northern Plains.
At this point, I really don't want to say what this winter will bring. With its unique weather patterns and variables, I cannot accurately use analogues to predict the winter temperature, snowfall, or precipitation. At this point, I'm going to lean on the side of caution. Quite a bit of data would suggest that a colder than normal winter is coming for the U.S. Some data would suggest that we will receive a warmer winter. In the history records, there have been two years that came out of a true double dip La Nina into an ENSO neutral or weak El Nino year, and one year that came out of an elongated La Nina. The two years that became a weak El Nino after the "double dip" La Nina were extremely cold years. The year that became a weak La Nina winter after the elongated La Nina, featured warmer temperatures across the East and cooler conditions in the West. At this point, the weather patterns are most similar to that of the first set of years, which occurred after a "double dip" La Nina. This would indicate that this upcoming winter could feature the same. More data will have to come up to prove this, but it is a very possible scenario. The only reason that I won't confidently project the idea of a very cold winter is because of what happened last year. For a few weeks I will wait and see what will happen.
For some entertainment, here is a map providing the average temperature anomaly across the United States from the winters of 1977-1978 and 1976-1977..
Temperatures during those two winters averaged nearly 10 degrees below normal.. According to archives and other records, the two winters featured extreme arctic cold, and several notable blizzards and snowstorms.
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