onNAV Storm

Storm warnings for the places you care about, drawn where the National Weather Service drew them. A new onNAV app for the US.

A Tornado Warning, with the minutes left and NWS’s words

The map, with the warning drawn as NWS drew it

A coastal place with its buoy camera and the day’s tide

The Lock Screen: the warning and its countdown

Every place, each with what NWS says about it

The pitch. A storm alert app that looks and feels like MarNav. It rings only when a warning covers where you are, and watches the places your people live. It runs on almanac, the data layer we already have: our own small servers in front of NWS and NOAA, so nothing sits between the sources and our apps. Warnings are free. Pro, at $19.99 a year, adds the heads-up before them, and the coast: tides, buoys and live buoy cameras.

What it does

Rings when a warning covers where you are, even on silent. Only then, so it’s believed when it does.
Watches your places. Home, a parent’s house, the beach house. The government’s Wireless Emergency Alerts only reach the phone where it is.
Draws the warning as NWS drew it. A shape, not the county around it. Mom’s in Moore hears “4 mi from a warning”, not a siren. Try it.
Counts down. The minutes left, on the warning, the Lock Screen and a widget.
Shows the coast. For a place by the sea: the nearest buoy’s camera, the day’s tide, the water, waves and wind. A Coastal Flood Advisory means more with the tide beside it.
Quotes NWS. What to do comes in NWS’s words, never ours.
No ads, no account, no tracking.

See all nine screens.

Built on almanac

almanac is how we get data into our apps without a middleman. It’s a set of small Cloudflare Workers, one per public source: NWS, the National Hurricane Center, NOAA’s buoys and tide stations, and more. Our apps ask almanac; almanac asks the sources. No reseller marks up free government data, no API key ships in an app, and a fix to a source lands once, for every app.

Seven of its services are live, the first since September 14. Storm adds one, alertq, for NWS warnings. The plan is simple: Gerry builds his own apps on almanac, onNAV builds Storm on it, and both get everything either one adds. How almanac works.

Who it’s for

Anyone in the US who lives with severe weather, and anyone whose people do. It goes in the App Store’s Weather category, found by searches like “tornado alert” and “storm warning”. Not storm chasers: RadarScope has them.

It looks like the rest of onNAV. Dark, the onNAV bar and menu circle, the map first, and color that means something. An instrument, not a weather toy.

The gap

The category is crowded, but not with this. Prices are what the listings showed in October 2026.

App	Price	What it lacks
Apple Weather	Free	Alerts for every saved place, but no map of the warning, no countdown, no say over what rings
FEMA	Free	5 places by ZIP code, which is coarse. Duplicate alerts
MyRadar	$29.99 a year, with ads	Ads in a safety app
Storm Shield	$29.99 a year	Alerts by shape, but reviews complain about price rises
RadarScope	$9.99, plus tiers	An expert’s tool
Local TV apps	Free	A 30-second video ad before the live stream, during a tornado

The opening: accurate to the shape of the warning, no ads, a fair price, real control over what rings, and the coast in the same app. Storm Shield proves people pay for the shape.

The weak spot. Apple Weather already alerts for every saved place, free. Storm can’t win on the number of places. It wins on precision, the countdown, quiet hours, the coast, and looking like it was made by people who take weather seriously. That’s why five places are free.

Money

Free, for good

Warnings where you are, rung on silent
Warnings for 5 places
The countdown on the Lock Screen and in widgets
The warning’s map and NWS’s words

Pro: $19.99 a year or $2.99 a month, 7 days free

Watches and advisories, pushed
Unlimited places, and quiet hours
Radar and the Storm Prediction Center’s outlooks
The coast: tides, buoys and buoy cameras

The rule: nothing that tells you to take cover is behind the paywall. $19.99 sits inside the $14.99–24.99 a year that radar apps charge, and under MyRadar and Storm Shield. Severe weather sells it: during Winter Storm Fern in January 2026, The Weather Channel went from about 9,000 downloads a day to 50,000.

What it proves for MarNav

XWeather’s alerts and tropical cyclones can go. almanac’s stormq already serves every active hurricane from the National Hurricane Center, free, and alertq will do the same for NWS alerts. XWeather’s US alerts come from NWS anyway.
Weather buoys can come from almanac. seaq serves the nearest buoys and their cameras today.
OneSignal can go. Storm sends to Apple directly. A load test first.
Lightning stays paid. No free source matches XWeather’s, so Storm ships without it.

The plan

November–December 2026: alertq in almanac, running against live NWS. Measure the time from a warning to a phone ringing, for a month.
January–February 2027: the app. Apply for Apple’s Critical Alerts on day one.
March 2027: TestFlight, with testers in Oklahoma, Kansas and the Gulf.
April 2027: the App Store, ahead of the peak of tornado season.

Open questions

Ownership. onNAV LLC, like Anchor Alert, on onNAV’s developer account.

The icon. Teal is the pick; slate and amber are on the Design page.

Mapbox. Does MarNav’s plan cover a second app’s maps?

Radar. Draw NOAA’s radar into our own tiles in almanac, or ask Iowa State to use theirs.

Critical Alerts. Apple grants it by hand. MyRadar and StormWatch+ have it for tornado and severe thunderstorm warnings.

A proposal; no app exists yet. The screens are drawn from the style guide over real maps, a real tide and a real buoy camera. Research dated October 31, 2026.

onNAV Storm • A pitch for onNAV, October 2026 • Built on almanac