The start of next week may be very wet! Also, the 1 and 3-month outlooks are wet. Just so you know.
But, after posting a link on Facebook to Scientific American article (How This Year’s El Niño Compares with the Past), I got a challenging question from MN about the winter of 1992-1993. In deed, this was probably one of the wettest winters in the last 60ish years. In December of 1992, Flagstaff received 6.78 inches of liquid water precipitation. In January and February of 1993, Flagstaff received 9.55 and 10.05 inches of precipitation. Also, these months were part of a longer term wet period. In the 12 months before the end of February 1993, Flagstaff reached over 48 inches of water. That more than double our typical one year normal. This peak is clear in the chart below.
12-month and 2-year Flagstaff precipitation totals.
It looks like the winter of 1992-1993 must have been an El Niño year. In 3 months, about 27 inches of water. Must have been….
The winter of 1992-1993 was not a El Niño winter. But, it overwhelmingly surpassed the so-called Great El Niño of 1997-1998. It was about as close to La Nada, neither El Niño or La Niña, as it could get.
Maybe because of my recent readings, the Atlantic Multidecadal Oscillation (AMO) came to my mind. This is a very long-term change in Atlantic Ocean temperatures. I covered it a bit in my last post. With neutral Pacific conditions, perhaps the AMO was in the driver’s seat.
Atlantic Multidecadal Oscillation Index. (http://www.esrl.noaa.gov/psd/data/timeseries/AMO/)
The AMO went from nearly positive to considerably negative in the time leading up to that winter. So, I think at least from a non-expert, looking at a couple of charts point-of-view, the Atlantic could have been an important factor in the winter of 1992-1993 for Flagstaff.
Also, notice that was the last hurrah for wet conditions. After that winter, the AMO started to switch to a persistent positive mode. From my last post, there is a linkage between positive AMO conditions and drier conditions for the American Southwest.
One more note. Many of the people who are my age and grew up in Flagstaff in the late 1960s through the early 1990s, have a profound impression of Flagstaff having been much wetter growing up. On the other hand, some of the people who grew up before that time frame, seem to remember a drier time that was more like today. Completely anecdotal, but interesting.