nexrad-radar-data

v0.2.0

A javascript implementation for decoding Nexrad Level II radar archive files. It currently does not support decoding bzip compressed radar data, or non-highres radar data.

You can find more information on how radar data is encoded at NOAA

Contents

1. Install
2. Usage
3. Examples
4. API
5. Known Issues
6. ToDo
7. License

Install

$ git clone https://github.com/bartholomew91/nexrad-radar-data.git

Usage

const { Level2Radar } = require('./index')
const file_to_load = "KTLX20130420_205120_V06" // The radar archive file to load

new Level2Radar(file_to_load).then(radar => {
    console.log(radar.getHighresReflectivity())
})

Examples

You can find an example of using the library HERE

API

setElevation(Number elevation)

Sets the elevation you want to grab the data from

setScan(Number scan)

Sets the current scan you want to grab the data from

setSweep(Number sweep)

Alias for setScan

getHighresReflectivity()

Returns an Object of radar reflectivity data for the current elevation and scan in the following format

{ 
  	gate_count: Number,
	first_gate: Number,
	gate_size: Number,
	rf_threshold: Number,
	snr_threshold: Number,
	scale: Number,
	offset: Number,
	data_offset: Number,
	moment_data: Array
}

getHighresVelocity()

Returns an Object of radar velocity data for the current elevation and scan in the following format

{ 
  	gate_count: Number,
	first_gate: Number,
	gate_size: Number,
	rf_threshold: Number,
	snr_threshold: Number,
	scale: Number,
	offset: Number,
	data_offset: Number,
	moment_data: Array
}

getHighresSpectrum()

Returns an Object of radar spectrum data for the current elevation and scan in the following format

{ 
  	gate_count: Number,
	first_gate: Number,
	gate_size: Number,
	rf_threshold: Number,
	snr_threshold: Number,
	scale: Number,
	offset: Number,
	data_offset: Number,
	moment_data: Array
}

getHighresDiffReflectivity()

Returns an Object of radar diff reflectivity data for the current elevation and scan in the following format

{ 
  	gate_count: Number,
	first_gate: Number,
	gate_size: Number,
	rf_threshold: Number,
	snr_threshold: Number,
	scale: Number,
	offset: Number,
	data_offset: Number,
	moment_data: Array
}

getHighresDiffPhase()

Returns an Object of radar diff phase data for the current elevation and scan in the following format

{ 
  	gate_count: Number,
	first_gate: Number,
	gate_size: Number,
	rf_threshold: Number,
	snr_threshold: Number,
	scale: Number,
	offset: Number,
	data_offset: Number,
	moment_data: Array
}

getHighresCorrelationCoefficient()

Returns an Object of radar correlation coefficient data for the current elevation and scan in the following format

{ 
  	gate_count: Number,
	first_gate: Number,
	gate_size: Number,
	rf_threshold: Number,
	snr_threshold: Number,
	scale: Number,
	offset: Number,
	data_offset: Number,
	moment_data: Array
}

Known Issues

1. RHO moment data parsing is not working

ToDo

• Add bZip data decompression for newer archives
• Allow loading from tar files and web
• Add non-highres reflection and velocity data

License

This work is based on the project of Unidata

MIT © Matt Johnston