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
   202008    -0.52
   202009    -0.93
   202009    -0.93
   202010    -1.30
   202011    -1.56
   202012    -1.71
   202101    -1.59
   202102    -1.25
   202103    -0.82
   202104    -0.49
   202105    -0.29