Hermes Weather Plugin

Weather plugin for Hermes Agent.

It provides 13 tools for observations, forecasts, alerts, model imagery, radar, soundings, calculations, and ECAPE. The plugin is packaged for Hermes plugin autodiscovery and bootstraps its Rust backends on first use instead of requiring users to clone and build multiple repos by hand.

Install

bash`r`npip install git+https://github.com/FahrenheitResearch/hermes-weather-plugin.git`r`n

Then start Hermes normally:

hermes

Hermes should auto-discover the plugin through the Python entry point.

Runtime model

The plugin is Python-first, but several heavy paths use Rust binaries or Rust-backed Python packages.

• Data tools call NWS, SPC, METAR, and Open-Meteo directly from Python.
• wx_model_image uses rusbie for model access, tries the newer wrf-rust render path first, and falls back to rustweather where needed for GRIB model-map rendering.
• wx_radar_image and wx_storm_image use a radar backend binary.
• wx_ecape uses the ecape-rs runner.
• wx_calc and wx_sounding use metrust in-process.

If a required Rust binary is missing, the plugin will try to build it on first use into:

• ~/.hermes/weather/bin

and cache downloaded source/build work under:

• ~/.hermes/weather/src

First-use bootstrap

The plugin can bootstrap these binaries automatically:

• radar-render from rustdar
• run_case from ecape-rs
• bundled nexrad-render-cli

This requires a working Rust toolchain (cargo, rustc) on the user machine unless they point the plugin at prebuilt binaries.

If you already have binaries installed, set optional overrides:

export RADAR_BACKEND=rustdar
export RADAR_RENDER_PATH=/path/to/radar-render
export NEXRAD_RENDER_PATH=/path/to/nexrad-render-cli
export ECAPE_RS_RUNNER=/path/to/run_case

Windows PowerShell:

$env:RADAR_BACKEND = 'rustdar'
$env:RADAR_RENDER_PATH = 'C:\path\to\radar-render.exe'
$env:NEXRAD_RENDER_PATH = 'C:\path\to\nexrad-render-cli.exe'
$env:ECAPE_RS_RUNNER = 'C:\path\to\run_case.exe'

Tools

Data

Tool	What it returns
wx_conditions	Current observed conditions
wx_forecast	NWS 7-day or hourly forecast
wx_alerts	Active NWS alerts
wx_metar	Raw and decoded METAR
wx_brief	Conditions + short forecast + alert count
wx_global	Global weather via Open-Meteo
wx_severe	SPC categorical outlook + active watches

Images

Tool	What it returns
wx_model_image	Model field PNG rendered with wrf-rust
wx_radar_image	NEXRAD Level 2 radar image through the configured radar backend
wx_storm_image	Reflectivity image with storm-analysis overlays and metadata

Calculations

Tool	What it returns
wx_calc	Rust-backed meteorological calculations through metrust
wx_sounding	Model sounding plus derived parameters
wx_ecape	ECAPE, NCAPE, CAPE, CIN, LFC, EL, storm motion, optional parcel path

Model support

Verified model subsets currently exposed in Hermes:

• wx_model_image
  • aigfs, gdas, gefs, gfs, graphcast, hiresw, hrrr, hrrrak, nam, nbm, rap
• wx_sounding
  • gdas, gfs, graphcast, hrrr, hrrrak, rrfs
• wx_ecape
  • same verified profile subset as wx_sounding

Models outside those sets may exist lower in the backend stack, but they are not exposed until their Hermes extraction path is verified.

Radar

Hermes keeps a stable radar tool contract and routes it through the configured radar backend.

Current backends:

• rustdar (default)
• nexrad

Supported radar products:

• both backends: ref, vel, sw, zdr, rho, phi
• rustdar only: srv, vil

Soundings and ECAPE

wx_sounding downloads a verified model pressure-level profile and computes:

• CAPE/CIN: surface-based, mixed-layer, most-unstable
• LCL/LFC/EL
• LI, K-index, Total Totals
• bulk shear and SRH
• precipitable water, lapse rates, freezing level
• standard pressure-level profile output

wx_ecape runs the parity-verified ecape-rs runner on the same profile.

Defaults:

• cape_type=most_unstable
• storm_motion_type=right_moving
• pseudoadiabatic=true

Supported storm-motion modes:

• right_moving
• left_moving
• mean_wind
• user_defined

Set include_parcel_profile=true to return the aligned parcel path arrays.

Packaging notes

This package is intended to be installed with pip from GitHub, not copied manually into ~/.hermes/plugins.

The package exposes the Hermes plugin entry point directly, ships plugin.yaml, ships the bundled nexrad-render-cli source, installs the bundled skill on first load, and bootstraps Rust binaries on demand.

Stack

Plugin (Python)
  |- Data: requests -> NWS / SPC / METAR / Open-Meteo APIs
  |- Model images: rusbie -> wrf-rust
  |- Radar: rustdar or bundled nexrad-render-cli
  `- Calculations: metrust + ecape-rs

Dependencies

Python package dependencies:

• requests
• numpy
• metrust
• rusbie
• rustweather
• wrf-rust

Optional system dependency for first-use binary builds:

• Rust toolchain (cargo, rustc)

Credits

• Solarpower07 for model imagery color tables and product styling
• metrust for Rust-backed meteorological calculations
• ecape-rs for the parity-verified ECAPE runner
• Hermes Agent by Nous Research