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Extreme Water Levels for Stations in District of Columbia
Monthly highest and lowest water level records are affected by the monthly Mean Sea Level (MSL) which combines both longer-term ocean fluctuations and vertical land motion at the station. Water level variations include the linear trend, the average seasonal cycle, and the interannual variability at each station in addition to the tropical and extratropical storm surges. Exceedance probability levels were derived for all stations with at least 30 years of monthly extreme values.