CFSv2 Seasonal SSTs (clim19912020)
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
   202505    -0.05
   202506    -0.00
   202507    -0.11
   202508    -0.24
   202509    -0.38
   202510    -0.45
   202511    -0.51
   202512    -0.48
   202601    -0.35
   202602    -0.17