JB tweeted this: Rare high amplitude phase 8 MJO for Feb being forecasted only 3 times last 40 years.. 1999,1988,1978
Went back and did composites for Feb of each of those three years; 1999 was warm (the month before - Jan - was also very warm, if not a "torch"), 1998 was cool (preceding Jan was very cool), 1978 was cold (as was the preceding Jan) (won't hog up a page showing all those maps LOL). Point being that even a strong Ph8 MJO doesn't always have the right mojo
Thanks, Phil. I bolded what I think is an excellent point you made that can be applied to any single index. These indices are tools that work best when other tools (other indices) are used at the same time.
Further to what JB mentioned about high amp Feb phase 8, I'm going to repost some of the KATL temperature anomalies for these and other long stringed very high amp Feb phase 8 but I'll this time order them by strength instead of chronologically . 1988 was the strongest long stringed Feb high amp phase 8 followed by 1999, 2006, 1978 (there were actually two strings but the strongest one was the 4th strongest on record), and 2010:
1. 1988: 2/21-29. ATL averaged 1.4 colder than normal. No wintry precip.
2. 1999: 2/16-21. ATL averaged 0.8 warmer than normal. No wintry precip. Note that the MJO dropped to just outside the circle still in phase 8 just after this and got much colder with 0.4" of snow.
3. 2006: 2/4-9. ATL averaged 6.0 colder than normal & got a trace of snow.
Similarly to 1999, it then dropped to just outside the circle in phase 8 and got even colder with two days having a trace of snow.
4. 1978 two strings: 2/7-10 & 2/23-28. ATL quite cold with an average 8.7 colder than norm for the two strings combined. (Caveat: most of that winter was cold wherever was the MJO). They got two days with traces of snow.
5. 2010: 2/7-13. ATL was very cold with an average of 11.0 colder than normal along with a major snow (3.6") as well as a trace on another day! (Caveat: this was a very cold winter throughout regardless of where was the MJO thanks largely to historic levels of -AO/-NAO blocking.)