OK then - time for me to rip apart your forecast. JK. I actually agree with most of it.
Several points:
1) Regarding the collapse of the el nino -- MEI readings have dropped significantly over the past couple months; certainly a neutral signal in the tropical pacific now. ENSO region 3.4 reached a peak of +1.4c back in mid December; rapidly declined to +1.0 by the first week of January and +0.5 by the latter part of Jan. Climatologically speaking, el ninos are followed by moderate-strong la nina's many times. Some examples:
- 1997-98 strong nino: 1998-99 strong nina.
- 1994-95 mod nino: 1995-96 weak nina.
- 1987-88 mod nino: 1988-89 strong nina.
- 2004-05 weak nino: 2005-06 weak nina (close-call, some sources say neutral for '05-06)
- 1982-83 strong nino: 1983-84 weak nina.
- 1972-73 strong nino: 1973-74 strong nina.
- 1969-70 weak nino: 1970-71 mod nina.
- 1963-64 weak nino: 1964-65 mod nina.
One can clearly see there's a tendency for la nina's following el nino's. Subsurface temperatures have been cooling quite a bit in the central pacific indicative of a potential reversal in trade winds down the road. A weak la nina is certainly in the process of developing; and this not only has implications for the spring/summer, but also the hurricane season. Strengthening la nina's during the spring coupled with a +AMO (warm phase Atlantic) and -PDO are historically active Atlantic seasons. I'm probably getting ahead of myself here -- but I'm ready to say right now this will be a more active than last tropical season, as well as above the mean of 11 named storms. Not making a call now as Dr. Gray got burned last year putting out an early forecast. The el nino developed quicker than anticipated, essentially shutting off the Cape Verde season.
2) With respect to this spring. We're transitioning into a more negative decadal regime in terms of the PDO and NAO. What this implies is a greater tendency for -PNA/PDO couplets and -AO/-NAO couplets similar to what we saw back in the late 40's through the late 70's. The neg PNA signal can mean ridging in the eastern US, but with a weakly neg ao/nao hanging tough into early March I have a difficult time seeing any blowtorch warmth in the NE US. For now I believe the major positive anomalies will be centered back in the Lakes and Plains per Euro ensembles and GFS enm. mean. The Northeast should see a brief moderation next week as I posted in my other thread, before heading back below average the end of this month. However, that below normal period should only last a week or tow (into early March) rather than the 4-6 week persistent cold since mid Jan. I generally agree with your ideas, especially the middle and llate part of March being above normal in the eastern US. Also -- with a develping nina -- severe weather season is typically active -- strong northern branch w/ numerous short-waves spells plenty of T-storm activity in the plains. I'm not going beyond March here as that's even more of a guessing game -- but March does appear at least +2 IMO in the eastern 1/3 of the nation.
3) Third factor going for an above normal temp March is ENSO climatology. Below is a map of all March's following mod ninos:
[img width=600 height=370]
http://i9.tinypic.com/4fu9ik6.jpg[/img]
Above normal much of the northern CONUS. Precip agrees with the idea of below average in the East:
[img width=600 height=370]
http://i9.tinypic.com/2vcxd9w.jpg[/img]
Bottom line is this -- for us snowlovers -- we need something through the end of this month or the first week of March. I'm thinking after the 7th-10th we flip into the new weak nina type pattern.
NYC Metro Weather
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