Inundation Analysis Tool


1619000 Johnston Atoll, United States of America

Please see the data inventory to find a period with hourly or six-minute data available.
Data Inventory

Note that this is a historical station and data may be available between 1947-04-28 00:00:00.0 and 2003-02-19 23:59:00.0


Select a reference elevation and specify a date range for analysis.

You may select from an accepted tidal datum or specify a different elevation.
Most elevations on land are given relative to a geodetic datum such as NAVD88

All analysis results are presently provided in meters relative to the requested threshold.

Meters relative to MHHWFeet relative to MHHWDatum
MHHW 0.0 0.0 Mean Higher-High Water
MHW -0.075 -0.25 Mean High Water
DTL -0.337 -1.11 Mean Diurnal Tide Level
MTL -0.356 -1.17 Mean Tide Level
MSL -0.354 -1.16 Mean Sea Level
MLW -0.638 -2.09 Mean Low Water
MLLW -0.675 -2.21 Mean Lower-Low Water
User Specified Elevation         in       relative to   


Note: Data query is limited to a 10 year maximum and 1 month minimum date range when requesting an analysis of 6-minute data


6-minute Height and High Water Analysis
Hourly Height and High Water Analysis
Hourly Height Analysis