Current Predictions

Owned by Jonathan Brewer
Last updated: Jul 26, 2022
2 min read

Current Predictions for the Tory Channel are available with new data every ten minutes for the following locations:

  • loc_1 (174.3120, -41.2200)

  • loc_2 (174.3212, -41.2134)

  • loc_3 (174.3185, -41.2116)

  • loc_4 (174.3148, -41.2102)

  • loc_5 (174.3106, -41.2098)

  • loc_6 (174.3065, -41.2103)

  • loc_7 (174.3031, -41.2113)

  • loc_8 (174.2763, -41.2261)

  • loc_9 (174.2552, -41.2397)

  • loc_10 (174.2262, -41.2409)

  • loc_11 (174.2011, -41.2405)

  • loc_12 (174.1796, -41.2456)

  • loc_13 (174.1604, -41.2473)

  • loc_14 (174.1546, -41.2386)

  • loc_15 (174.1526, -41.2300)

JSON Format

A JSON packet is produced once every ten minutes, with a 30 minute delay, and uploaded to the Council’s data lake:

  • timestamp is in UTC

  • lat/lon are in WGS84 decimal degree format

  • height is Surface elevation above MSL in meters

  • east_velocity is Eastward surface current velocity in m/s

  • north_velocity is Northward surface current velocity in m/s

  • current_direction_true is the surface current direction in degrees true North

  • current_direction_magnetic is the surface current direction in degrees magnetic North (22.5 degree offset)

  • current_speed_knots is the current speed in knots

  • measurement_id is unique for every ten minute period

JSON format example:

{ 'loc_name': 'tory_loc_15', 'timestamp': '2022-07-08T07:40:00Z', 'lat': -41.23, 'lon': 174.1526, 'height': -0.004463135070520845, 'east_velocity': -0.014527322724461555, 'north_velocity': 0.045555416494607925, 'current_direction_true': 342.31, 'current_direction_magnetic': 319.81, 'current_speed_knots': 0.09, 'measurement_id': '6cc86cb02f1d85bed2b35a1e9210892c' }

NMEA Format

One sentence type is produced and sent once a minute, with all data on a 30 minute delay. Each sentence is followed by a CR/LF. Sentences contain:

  • Current direction in degrees True North (“T”)

  • Current direction in degrees Magnetic North (“M”)

  • Current speed in knots (“N”)

NMEA format sentence example:

$VDR,126.69,T,104.19,M,00.05,N,*17

One TCP port is provided for each location, with ports ranging from 12101-12115 and the last two digits of the port number corresponding with the location ids above.