The EPS/GEFS project a 2.5/3.0 amp MJO 4/5 late next week. If this one were to peak near 3, would it be a record strong 4/5 for winter? No, because it peaked at 4.1 in Feb of 1985. Also, it peaked at 3.15 in Jan of 1986. If it peaks at ~3.0. it would become the 3rd strongest on record for winter. THE GEFS does tend to overdo amps although the EPS sometimes is too low. So, I suspect it will peak between them. So, I'm guessing it will peak near 2.75 amplitude in 4/5.
- How many periods on record has there been a ~2.5+ peak of 4/5 in winter? 14
- How many of those 14 had a +NAO? 12 ( 1 was neutral and 1 was -NAO)
- How many of those 14 had a +AO? 7 (4 were neutral and 3 were -AO)
- How many of those 14 had a -PNA? only 4 (3 were neutral and 7 were +PNA)
- How many of those 14 had a +EPO? 8 (2 were neutral and 4 were -EPO)
- How many of these 14 periods were AN at KATL? only 9 with 5 BN; The 14 periods averaged only +1
- Average length of strong 4/5 in winter? 6 days or about how long the upcoming one is projected to be
- The warmest anomalies were these: +12, +10, +9, +9, +8, +7, +4, +3, +3
- The coldest anomalies were these: -10, -8, -5, -5, -4
- The coldest anom of -10 was for 1/20-31/1978, when there was -AO, +PNA, and -EPO to go along with +NAO. Also, that was a wk Nino.
- The 2nd coldest anom of -8 was for 1/6-7/2015, when there was a +PNA/-EPO to go along with +NAO/+AO. Also, that was a wk Nino.
- The 3rd coldest anom of -5 was for 2/12-22/1985, when there was a -AO/+PNA to go along with neutral NAO/+EPO.
- The 4th coldest anom of -5 was for 2/1-8/2004, when there was - -NAO/+PNA to go along with a neural AO/+EPO.
For the upcoming one, the GEFS forecast is for a +NAO/+AO/-PNA and I think a +EPO is being forecasted, also. So, that is like all 7s for warmth on the "indices slot machine.". So, a very warm period close to the warmest of the ones I listed, +7 to +12, wouldn't surprise me.