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
   201712    -0.86
   201801    -0.88
   201802    -0.85
   201803    -0.80
   201804    -0.75
   201805    -0.66
   201806    -0.62
   201807    -0.60
   201808    -0.65
   201809    -0.74