anchor.diff:                  "observedPeriod": "PT3H",
                   "pressureChangeInHectoPascal": 2,
                   "pressureTendency": "INCREASING_THEN_STEADY",
  +                "pressureTendencyCode": 1,
                   "precipitationAmountInMillimeter": 1.2,
                   "precipitationAmountInInch": 0.047
                 },
  
positive.code:                 "observedPeriod": "PT3H",
                  "pressureChangeInHectoPascal": 2.0,
                  "pressureTendency": "INCREASING_THEN_STEADY",
                  "precipitationAmountInMillimeter": 1.3,
                  "precipitationAmountInInch": 0.051
                },
  
negative.code:                 "observedPeriod": "PT3H",
                  "pressureChangeInHectoPascal": 2.0,
                  "pressureTendency": "INCREASING_THEN_STEADY",
                  "pressureTendencyCode": 1,
                  "precipitationAmountInMillimeter": 0,
                  "precipitationAmountInInch": 0
                },
  