Many stations on the Gulf coast have large values for September 1961.
Documentation added 2011-11-24
Using information from the NOAA website the RLR diagram has been revised. Previous Primary benchmark BM 1 no longer appears on the NOAA website. Primary benchmark is now NO 7 1974 4.225m above gauge datum. This benchmark is included in the original RLR diagram as a secondary benchmark with the same value.