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
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.
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.
v0.0.5LatestJuly 16, 2026
A data and routing release headlined by the new MCD Archive tab and Discord webhook alerts, alongside a deeper SPC Archive, a new Glass theme, and major connection fixes.
MCD Archive Tab: A dedicated tab for pulling up past Mesoscale Convective Discussions by date, with the full discussion text and its associated graphic, bringing MCDs in line with the existing SPC outlook archive.
Discord Webhook Alerts: Route live alerts straight out of StormSync into any Discord channel through a configurable webhook. Pick which alert types get forwarded, and your server is notified the moment a warning is issued.
SPC Archive Expansion: Historical convective outlook retrieval now reaches back to 2003, up from October 2019.
New Glass Theme: A translucent, layered interface theme built to match the website's design language, selectable alongside the existing themes in settings.
Fixes and Improvements
Central Feed Reliability: Repaired the issues that were causing Central Feed to stall or drop alerts. Relayed alerts now arrive consistently.
Private Account Freezes: Fixed the sudden freezes that could occur while connected with your own NWWS-OI credentials.
Stream Tab: Temporarily disabled while its elements are reworked. It returns in the next patch.
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.
