Live Level II radar visualization

Volumetric Radar Echo Map

VREM is a browser based 3D WSR-88D radar viewer built for reading storm structure fast: all tilts, live scans, warning polygons, county and state outlines, and a satellite style map in one volumetric scene.

Install VREM Beta Read the field notes

Install

Download the package, unzip it, and start VREM from the top level startup file. The app runs locally in your browser and keeps the source files included with the download.

VREM is a beta visualization and research tool. It is not for making life threatening decisions and has the rare possiblity produce errors or false radar data.

Field Notes

Live Radar

  • Loads newest public NEXRAD Level II scans.
  • Displays Reflectivity, Base Velocity, Storm Relative Velocity, and Correlation Coefficient.
  • Refreshes automatically when new live scans appear.

3D Volume

  • Shows all tilts together by default.
  • Includes tilt range isolation and height readouts.
  • Uses soft particles, alpha curves, and distance scaling for readability.

Map Context

  • Satellite style ground reference.
  • County outlines, state borders, and range rings.
  • Tornado, severe thunderstorm, flash flood, and watch polygons.

How To Use VREM

VREM runs as a local browser app. Download it, unzip it, click the startup file for your OS, then use the browser window it opens.

One Start File

Windows: double-click Start_VREM.bat.

Linux: open a terminal in the folder and run bash Start_VREM.sh.

The startup script creates or verifies the local Python environment and starts the VREM server.

Browser And Mobile

If the browser does not open automatically, use the URL printed in the terminal, usually http://localhost:5000.

For phones or tablets, start VREM on a computer first, then open the printed Mobile/LAN URL on the same Wi-Fi.

Folder Organization

Volumetric Radar Echo Map> How_To_Use.html Offline User Guide Start_VREM.bat Windows Launcher Start_VREM.sh Linux Launcher .VREM> The Brains of VREM .cache> Radar Download Cache .venv> Local Python Environment data> Server Data static> Browser Assets templates> Flask HTML Files .gitignore Git Ignore Rules app.py Main VREM Server requirements.txt Required Python Dependencies VREM.bat Internal Windows Launcher vrem.sh Internal Linux Launcher wsgi.py Server Entry Point

Basic Workflow

  1. Start VREM and wait for the WSR-88D site selector.
  2. Search for a radar site, city, or state, or click a radar dot.
  3. Wait for the newest live Level II scan to download and parse.
  4. Use product buttons, tilt range, and vertical exaggeration to inspect storm structure.
  5. Use Change Radar to return to site selection.

Radar Products

  • REF: reflectivity for precipitation and cores.
  • BV: base velocity for inbound and outbound winds.
  • SRV: storm-relative velocity using VREM storm-motion handling.
  • CC: correlation coefficient for debris or hydrometeor changes.

Controls

  • Tilt Range: isolate selected tilt layers.
  • Vert Exag: improve vertical readability without changing radar data.
  • Tilt Heights: show displayed tilt heights at 100 km.
  • Settings: save UI scale, default tilt range, opacity, performance, and renderer preferences.

Requirements

  • Windows 10/11 or a modern Linux desktop to run the local server.
  • Modern Chrome, Firefox, Edge, or Safari based browser.
  • Internet access for live radar, warnings, borders, counties, and imagery.
  • A dedicated GPU is recommended for smoother 3D radar volumes.

Archive

  • Moved from simulated radar to live NEXRAD Level II data.
  • Updated the Level II source to the public Unidata archive.
  • Added automatic live refresh checks.
  • Added tilt range isolation.
  • Added tilt height readouts.
  • Added reflectivity and velocity alpha controls.
  • Added performance controls.
  • Added a custom satellite map layer.
  • Added state borders, county outlines, range rings, and warnings clipped to radar range.
  • Added lightly filled warning polygons.
  • Removed simulated radar mode.
  • Removed the terrain toggle and TDS finder from the UI.
  • Added saved settings and presets.
  • Added Linux startup support.

Open Source

VREM is source available for learning, research, and personal modification. The code is meant to stay readable, remixable, and understandable. You may use or modify it for personal, educational, and noncommercial projects, but commercial use, public redistribution, or republishing requires explicit permission.