StormSync VT/OI listens directly to the NWWS-OI, or NOAA Weather Wire Service Open Interface,
the same live circuit that feeds broadcast desks and emergency operations centers. The moment a
warning is issued it is on your screen: decoded, ranked, color-coded by severity, and announced
by tiered audio tones.
Sample output · Colors match the app's severity tiers
StormSync VT/OI — Example Session
<100msWire delivery after issuance
115Point severity rank scale
5Tornado warning tiers
100%Data stored locally
Made for streamers. StormSync is being built so streamers can put live severe weather on their broadcast with ease. The next few updates are hyper-focused on stream elements. Work in progress: expect rapid changes and more to come. See stream elements
The Feed
What is NWWS-OI?
The NWS pushes alerts through several channels. Most weather apps pull from the public
REST API at api.weather.gov, which typically adds 60 to 120 seconds between
issuance and delivery.
The NOAA Weather Wire Service Open Interface (NWWS-OI) is different: an
authenticated XMPP feed that broadcasters, emergency managers, and commercial alerting
services rely on. Products are pushed the instant they are published, arriving within about
100 milliseconds of issuance. It is the same wire that drives the Emergency Alert System
on broadcast television.
StormSync makes that feed available as a free desktop application. No aggregators in the
middle, no polling delays. The wire, decoded on your machine.
Typical delivery delay by channel
NWWS-OI (StormSync)<100 ms
NWS REST API60–120 s
Typical weather apps2–5 min
Mobile push notifications3–10 min
Bars are scaled for comparison, not to absolute time. The point is the order of magnitude:
a push feed versus a polling cycle.
Signal Path
Issuance to your screen, in three hops.
No aggregator sits between the forecast office and your machine. That is the entire design.
01 — Issue
The forecast office publishes
A Weather Forecast Office or National Center issues a text product. It is pushed onto the Weather Wire immediately.
02 — Push
NWWS-OI broadcasts it
The product is emitted over an authenticated XMPP connection as a message stanza carrying the raw product text. No polling, no waiting for a refresh interval.
03 — Decode
StormSync parses locally
Your machine reads the VTEC and UGC codes, classifies the tier, assigns a severity rank, fires the tone, and writes the record to a local database.
Capabilities
Built like a broadcast tool.
Every part of StormSync exists to put critical information in front of you faster and cleaner than anything else a civilian operator can run.
Connection
A direct line to the wire
StormSync authenticates straight to NWWS-OI over XMPP and holds the connection open. No third-party aggregators, no polling delays. Products land on your machine the same moment they land at broadcast stations.
Parsing
Every product, fully decoded
Each product is broken down at the VTEC level: phenomena codes, significance, UGC zones, and action strings. Tornado warnings split into five sub-types, each with its own rank from 1 to 115.
Display
Severity at a glance
Every tier carries its own distinct color, from Tornado Emergency down to routine advisories. Accent colors are customizable and persist across sessions.
Products
The full SPC toolset, built in
Beyond warnings: Day 1 through Day 8 convective outlooks, Mesoscale Discussions, active watches on a map layer, and a warnings map drawing every polygon in the database.
Audio
Tones that escalate with severity
Each tornado tier has its own distinct sound, so your ears know what just happened before your eyes do. Any default tone can be replaced with your own audio file, and notifications can be enabled per alert type.
Storage
Your history stays on your machine
Every alert received is written to a local SQLite database with full metadata intact. Nothing leaves your computer. The complete history stays available for post-event analysis.
Alert ListAlerts as they arrived during a real session.
Alerts in Action
Every alert, in one clean list.
Alerts land in a live list the moment they arrive, with warnings and watches kept
apart in their own tabs so nothing important gets buried.
Notifications pop up on screen as products come in, so you know what was just
issued even when StormSync is not the window in front of you.
NotificationsReal alert notifications as they appear on screen.
Maps
See what is active, and where.
Watches and warnings drawn straight onto the map. Click any frame to view it full size.
Watches MapA look at active watches on the map.Warnings MapWarnings across the entire US.
Built-in RadarA small built-in radar for quick, convenient map checks.
Built-in Radar
A quick look, right on the map.
StormSync includes a small built-in radar for convenient map viewing, so you can glance at
what is happening without leaving the app.
Not a replacement for high-level radar software. It is a convenience view and is not meant to stand in for dedicated tools like GR2Analyst, RadarScope, or WeatherFront.
Stream Elements
Built for streamers.
Stream elements were completely overhauled in v0.0.60. Pick the one that fits your broadcast.
Stream ElementsPicking a stream element for your broadcast.
Map Stream Element: ReflectivityReflectivity map element that automatically zooms to each new alert.Map Stream Element: VelocityThe same element showing velocity instead of reflectivity.
Your Layout
Start from a template, make it yours.
Begin with the default template, then customize everything: sources, cameras, facecam, and more. Add the elements you want and remove the ones you don't.
Default TemplateThe default template, showing where elements can go. Sources, cameras, facecam and more can all be modified.Customized LayoutAn example of a filled-in stream layout. Add what you want and remove what you don't.
Streamer RemoteControl your stream elements from one panel.
Streamer Remote
Run your overlays without touching OBS.
The Streamer Remote lets you manage a variety of your stream elements live, without
manually changing anything in OBS.
Toggle alert popups, map auto-jump, the emergency takeover, and sponsor rotation. Clear
popups, zoom out to everything, post a breaking banner, and see every alert currently
on stream, each with its own controls.
Work in progress. The next few updates are hyper-focused on stream elements, with more elements, options, and polish on the way.
Screenshots
Straight from live sessions.
Real captures from the app. Click any frame to view it full size.
SPC OutlookAn official SPC outlook with categorical, tornado, hail, and wind probability layers.Alert FeedTornado warnings across four escalation levels: standard, confirmed, PDS, and emergency.SPC ArchiveHistorical outlooks reaching back to 2003.
Changelog
Latest release.
StormSync moves fast. Here is the current build in full. Older releases live on the History page.
StormSync VT/OI is in active development and ships updates often. If something breaks or behaves unexpectedly, please reach out at [email protected] so it can be fixed quickly.
v0.0.63LatestOctober 11, 2026
The Streamer Update: a new live radar warnings map, a full set of redesigned stream overlays, and tools built for storm streamers.
What's New
Radar Spotlight: The Warnings tab is now a live radar map with every active warning drawn on top. It auto-jumps to each new warning, offers General, Detailed, Velocity or no radar, and can be popped out or docked beside any other tab.
Watches, MCDs and SPC Outlooks: A new polygon style with an optional radar layer, plus fixed lag when zooming in close.
Alert Map Radar: The alert card map can now switch between Composite, Reflectivity and Velocity radar.
Storm Arrival Times: Warnings with a storm motion show which towns are in the path and when the storm should arrive, on alert cards, notifications, stream popups and the Streamer Remote.
Streamer Remote: A control panel for your stream: pause popups, map auto-jump and the Emergency Takeover, spotlight, re-announce or hide alerts, post a breaking banner, and more. It can sit in a tab, float, or dock to the side.
Full Stream Overlay: A complete broadcast layout in a single OBS source, with slots for radar, facecam and extra cameras, a built-in alert map, counts, SPC risk, popups, ticker and clock. The frame takes the color of the highest active alert. Includes optional socials, layout options, placement guides and a Reset to Default button.
New Stream Overlays: Emergency Takeover, SPC Risk widget, Sponsors, Socials, and Radar Spotlight as a stream overlay.
Redesigned Overlays and Notifications: Every stream overlay was rebuilt with the new look and loads reliably in OBS. In-app notifications gain a mini map, tags, expiry and arrival times, and the Alert Ticker has a custom bar height.
Test Alerts: Injected test alerts are never saved and are cleared from your stream on logout. A new "Send on alert map" option controls whether a test alert moves your stream map.
Fixes and Improvements
Overlay Warnings After Restart: Fixed stream overlays losing active warnings after restarting the app.
Jump to Card: Fixed Jump to Card not working for real alerts.
Radar Fixes: Fixed radar not returning after switching modes, a faint composite showing behind Detailed radar, and a square glow around warnings when zoomed out.
Streamer Remote and Sponsors: Fixed the sponsor card being cut off and spotlighting real alerts from the Streamer Remote.
Get Started
Put the wire on your screen tonight.
Access is free. Download StormSync, choose Central Feed, and you are live in seconds. No credentials required.
