Dissemination and its gaps
A warning that nobody receives is a file on a server. This lesson follows the product out of the office and finds the places it stops.
The chain out of the office
- NWWS
- NOAA Weather Wire Service. The bulk feed of text products, which is what media, vendors and downstream systems consume.
- GOES / EMWIN
- The Emergency Managers Weather Information Network, broadcast down from the Geostationary Operational Environmental SatelliteThe NOAA weather satellites parked over a fixed point above the equator, watching the same hemisphere continuously. They carry the imagery and lightning detection this site uses, and they also broadcast warning text back down. satellites. The same warning text, arriving from orbit to anything with a receiver and a view of the sky, which is the point: it needs no internet connection and no phone network.
- NWR / SAME
- NOAA Weather RadioThe National Weather Service broadcasting its own products directly on dedicated radio frequencies. It keeps working when the internet and the phone network do not., with Specific Area Message Encoding so a receiver can stay silent for events outside its area.
- EAS
- Emergency Alert System. The broadcast interrupt on radio and television.
- WEA via IPAWS
- Wireless Emergency Alerts, routed through FEMA's Integrated Public Alert and Warning SystemFEMA's system for routing alerts from the agencies that issue them to the channels that deliver them, including WEA and the Emergency Alert System.. This is the one that reaches a phone with no app installed and no subscription.
- Media and apps
- Broadcasters and third-party services, this one included, that consume the feed and present it. Fast, ubiquitous, and not the official channel.
What actually sets off a phone
Not everything, and the list is shorter than most people assume. The National Weather Service has sent Wireless Emergency AlertsThe alerts that interrupt a phone with no app installed and nothing subscribed to. Only some weather products are eligible to send one. since June 2012, and it sends it only for warnings that need somebody to act in the next few minutes.
A local authority can still send its own alert about winter weather or anything else. This is what the weather service itself sends.
Two things are worth reading out of that table. The first is that the test is imminence, not danger. Blizzard and ice storm warnings came off the list in 2013 because they are issued well ahead of the weather, not because a blizzard is survivable. A snow squall warning, issued while it is happening, is on the list for exactly that reason.
The second is that the damage-threat tag from Lesson 5 is what opens the gate for the two warnings you will meet most often. A Severe weather is happening or about to happen for the people inside a drawn polygon. Issued by the local forecast office. It means act now. reaches phones only at the destructive tier, and since 2019 a flash flood warning reaches them only at considerable or catastrophic. The tag is not decoration. It decides who finds out.
Weather arrives as one of the four kinds of WEA: national alerts, imminent threat, AMBER alerts and public safety messages. All of the above are imminent threat alerts, and a carrier is permitted to let a subscriber switch that whole category off. Only national alerts cannot be blocked.
Those answer most of the complaints you will hear in the field. A neighbour who says the alert never came through usually received exactly what the system is designed to send. The expectation was wrong, not the delivery.
The gap between receiving and acting
The Joplin Service Assessment documented a durable finding: people who receive a warning frequently do not act on it immediately. They look for confirmation first, from a second channel, a neighbour, a window, the sky. The warning starts a decision rather than ending one.
Where WxAlerts sits
Downstream, and unofficial. This service redistributes NWS products and adds its own detection data on top. It is not a government source and not a replacement for one. If this site and NOAA Weather Radio disagree, the radio wins. How the feed reaches us and what we do to it is documented in how alerts work.
Your neighbour got no alert on their phone for a severe thunderstorm warning that covered their house, and they have never touched their alert settings. Why?
Look back at the tag table in Lesson 5.Most severe thunderstorm warnings are not WEA-eligible. Only the destructive tier, 80 mph wind or 2.75 in hail, sends one. The warning reached NOAA Weather Radio, the wire and every app on their phone. It did not reach the channel that interrupts a phone with no app.