Many stations on the Gulf coast have large values for September 1961.
Documentation added 2011-12-20
Using NOAA data the RLR diagram has been revised. Original RLR diagram had Primary benchmark BM1 5.672m above chart datum. This may correspond to the current Primary benchmark NO 1 1933 14.124 with a value of 5.669m relative to gauge datum as appears in the last two NOAA reports.