Years missing: 2000, 1975
NAO - Positive
January
February
Years missing: 2003, 1993, 1962
March
April
Years missing: 2011, 2009, 1966, 1961
Years missing: None
May
June
Years missing: None
Years missing: None
July
August
Years missing: None
Years missing: None
September
October
Years missing: None
Years missing: None
November
December
Years missing: None
Years missing: None