bom-nowcast — BOM radar CLI + nowcast

A fast, friendly BOM radar CLI for Australia: fetch Bureau of Meteorology radar frames, render a readable loop with emoji pins, and run a lightweight rain nowcast from your terminal.

This project intentionally avoids BOM FTP (which is often the source of hangs/timeouts) and instead scrapes the BOM loop pages and downloads the timestamped PNG frames over HTTPS.

Features

• Interactive setup (choose radar, set your default location, add emoji pins)
• Default run opens a looping radar GIF in mpv
• Cached frame fetch + auto-pruning
• Human-friendly loop rendering (background + labels + emoji pins)
• Basic rain nowcast with ETA window + intensity (likely + peak)
• Intensity ordering follows the BOM legend (white = light rain, black = hail)

Why this CLI?

• BOM radar from the terminal: quick checks without opening a browser
• Australia-focused: uses Bureau of Meteorology loop pages over HTTPS
• Readable output: labels + context map + emoji pins for locations

If you searched for bom cli radar, Bureau of Meteorology radar CLI, Australian weather radar command line, or BOM radar GIF, this is the tool.

Prerequisites

• Node.js
• ImageMagick (magick or convert) optional but recommended for GIF loops
• mpv optional but recommended for the default loop player

Install

From this folder:

npm install
npm link

If you prefer not to link globally, you can always run via node bom-nowcast.js ....

Quick start

bom-nowcast setup
bom-nowcast

Commands

Setup

Config lives at:

• ~/.config/bom-nowcast/config.json

Interactive setup (recommended):

bom-nowcast setup

If you prefer to create a default config without prompts:

bom-nowcast config-init

Default run (no arguments)

bom-nowcast

It will:

1. Ensure you have a config (launches setup if missing)
2. Render the latest loop with your emoji pins
3. Open it in mpv and loop until you close it

Locations (home/work/uni)

List locations:

bom-nowcast locations

Add a location:

bom-nowcast location-add --name Work --lat -27.XXXX --lon 153.XXXX

Add a location with an emoji marker:

bom-nowcast location-add --name Work --lat -27.XXXX --lon 153.XXXX --emoji 🧭

Set a location as the default:

bom-nowcast location-add --name Default --lat -27.874798 --lon 153.296172 --set-default

List supported radars

bom-nowcast radars

Fetch latest frames (cached + auto-prune)

bom-nowcast fetch --radar IDR663 --frames 10

Cache location:

• ~/.cache/bom-nowcast/<RADAR_ID>/

Build a human-friendly radar loop GIF (with map underlay + labels + location emojis)

bom-nowcast loop --radar IDR663 --frames 7 --out /tmp/bom-nowcast-context.gif

Open it:

open /tmp/bom-nowcast-context.gif

Nowcast (MVP)

Nowcast supports either:

• a named location from your config (recommended), or
• an explicit --lat/--lon

# Use your default configured location
bom-nowcast nowcast --frames 7 --mode local

# Use a named location
bom-nowcast nowcast --location Work --frames 7 --mode local

# Nowcast all configured locations
bom-nowcast nowcast --all --frames 7 --mode local

# Or pass lat/lon explicitly
bom-nowcast nowcast --lat -27.874798 --lon 153.296172 --frames 7 --mode local

Notes:

• --mode local focuses on a window around the target (better for “is it coming toward me?”)
• --mode global uses the broader precip field (can be noisier)
• ETA is shown as X ± N minutes (a window around the median arrival time)
• Intensity reports a likely band plus the peak band

Supported radars (built-in)

• IDR663 — Brisbane (Mt Stapylton)
• IDR503 — Brisbane (Marburg)
• IDR713 — Sydney (Terrey Hills)
• IDR023 — Melbourne (Laverton)
• IDR643 — Adelaide (Buckland Park)
• IDR703 — Perth (Serpentine)
• IDR633 — Darwin (Berrimah)
• IDR763 — Hobart (Mt Koonya)

Design notes

We keep machine-readable frames separate from human-readable composites:

• Machine-readable: raw timestamped PNG frames from the loop page (best for analysis)
• Human-readable: composited frames (background + labels) for GIF output

FAQ

Is this an official BOM tool?
No. It’s a community CLI that uses public Bureau of Meteorology loop pages over HTTPS.

Does it use BOM FTP?
No. It avoids FTP and downloads the timestamped PNG frames from the loop pages.

What platforms are supported?
Anywhere Node.js runs. ImageMagick and mpv are optional helpers for GIFs and playback.

Which radar should I choose?
Pick the radar closest to your area from bom-nowcast radars.

Can I run it without a GUI?
Yes. Use fetch and nowcast only, or write GIFs to a file path and view later.

References

• BOM loop pages: https://reg.bom.gov.au/products/
• BOM radar transparencies (legend/background/labels): https://reg.bom.gov.au/products/radar_transparencies/