Datums for 9440171, KNAPP(THORNES)LNDG, WILLOW BAR WA


NOTICE: All data values are relative to the MLLW.

Elevations on Mean Lower Low Water

Station: 9440171, KNAPP(THORNES)LNDG, WILLOW BAR, WA
Status: Accepted (Dec 28 2016)
Units: Feet
Control Station: 9439040 Astoria, OR
T.M.: 120
Epoch: 1983-2001
Datum: MLLW
DatumValueDescription
MHHW3.14Mean Higher-High Water
MHW2.61Mean High Water
MTL1.44Mean Tide Level
MSL1.36Mean Sea Level
DTL1.57Mean Diurnal Tide Level
MLW0.26Mean Low Water
MLLW0.00Mean Lower-Low Water
NAVD88-6.98North American Vertical Datum of 1988
STND-11.89Station Datum
GT3.14Great Diurnal Range
MN2.35Mean Range of Tide
DHQ0.53Mean Diurnal High Water Inequality
DLQ0.27Mean Diurnal Low Water Inequality
HWI0.96Greenwich High Water Interval (in hours)
LWI8.61Greenwich Low Water Interval (in hours)
Max TideHighest Observed Tide
Max Tide Date & Time Highest Observed Tide Date & Time
Min TideLowest Observed Tide
Min Tide Date & Time Lowest Observed Tide Date & Time
HAT3.99Highest Astronomical Tide
HAT Date & Time12/05/2021 01:30HAT Date and Time
LAT-0.72Lowest Astronomical Tide
LAT Date & Time01/03/2018 09:30LAT Date and Time
Tidal Datum Analysis Periods
08/01/2016 - 10/31/2016




Products available at 9440171 KNAPP(THORNES)LNDG, WILLOW BAR, WA