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Current Datum Value: 1.34

Datums for 1630000, Apra Harbor, Guam


NOTICE: All data values are relative to the MLLW.

Elevations on Mean Lower Low Water

Station: 1630000, Apra Harbor, Guam
Status: Accepted (Jun 20 2017)
Units: Feet
Control Station:
T.M.: 0
Epoch: 1983-2001
Datum: MLLW
DatumValueDescription
MHHW2.34Mean Higher-High Water
MHW2.22Mean High Water
MTL1.41Mean Tide Level
MSL1.37Mean Sea Level
DTL1.17Mean Diurnal Tide Level
MLW0.60Mean Low Water
MLLW0.00Mean Lower-Low Water
GUVD041.38Guam Vertical Datum of 2004
STND-1.34Station Datum
GT2.35Great Diurnal Range
MN1.62Mean Range of Tide
DHQ0.12Mean Diurnal High Water Inequality
DLQ0.61Mean Diurnal Low Water Inequality
HWI10.04Greenwich High Water Interval (in hours)
LWI3.92Greenwich Low Water Interval (in hours)
Max Tide4.29Highest Observed Tide
Max Tide Date & Time08/28/1992 18:54Highest Observed Tide Date & Time
Min Tide-2.34Lowest Observed Tide
Min Tide Date & Time10/24/1972 00:00Lowest Observed Tide Date & Time
HAT2.71Highest Astronomical Tide
HAT Date & Time01/20/1992 09:12HAT Date and Time
LAT-1.17Lowest Astronomical Tide
LAT Date & Time12/31/1986 16:12LAT Date and Time
Tidal Datum Analysis Periods
01/01/1983 - 12/31/2001




Products available at 1630000 Apra Harbor, Guam,

Revised: 08/08/2018
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services