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
   202109    -0.62
   202110    -1.02
   202110    -1.02
   202111    -1.54
   202112    -1.75
   202201    -1.72
   202202    -1.43
   202203    -1.05
   202204    -0.69
   202205    -0.40
   202206    -0.14