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
   202406     0.07
   202407    -0.28
   202408    -0.65
   202409    -0.93
   202410    -1.08
   202411    -1.15
   202412    -1.13
   202501    -0.96
   202502    -0.69
   202503    -0.37