CFSv2 Seasonal SSTs (clim19822010)
first  rec: avg(lastbs-1, lastobs, CFSv2 month 1)
second rec: avg(lastbs, cfs month 1, CFSv2 month 2)
last   rec: CFSv2 month 9
other  rec: CFSv2 3-mo average
 TrgSeason    SST34
   201702     0.05
   201703     0.32
   201704     0.53
   201705     0.67
   201706     0.70
   201707     0.68
   201708     0.64
   201709     0.70
   201710     0.80
   201711     0.90