Get an alert when your city turns
We’re collecting signups, not sending yet
US law (CAN-SPAM) requires a physical mailing address in every commercial email, and this project doesn’t have one to publish yet. Rather than send you something non-compliant, or pretend the list is live, we hold your signup until it is. You’ll get one email when alerts start — and nothing before that.
Your city crosses your number at some point this year. The only question: do you hear about it before you smell it, or after?
Pick your number, not the site’s
An asthmatic and a runner respond to identical air about 80% apart. Pick the profile closest to you at signup: asthma sits near 60, parent near 100, runner near 110. Or skip the presets and set your own number. Several runners and asthmatics who track their own numbers also drop that cutoff by roughly one EPA band. That happens once the cause is smoke, not ordinary pollution.
The message names the cause
An alert names the cause behind the number, not just the number itself. Denver crossing AQI 100 usually means wildfire smoke and ground-level ozone stacking together — a “double whammy,” per one widely-upvoted r/Denver post. Seattle crossing the same 100 usually means smoke alone. The bare number can’t tell the two apart; the alert message does.
Denver’s “double whammy” is wildfire PM2.5 drifting in combined with ground-level ozone cooked out of traffic and industry, the city sitting in a bowl of both at once. Seattle’s number usually means smoke, and on the days the sky looks worse than the number, it’s smoke still sitting aloft, above the monitor.
Not the map, not the forecast
An alert is neither the live AQI map nor the forecast. The map already shows today’s current reading; the forecast shows what’s coming next. An alert instead speaks once, the moment a chosen threshold in a chosen city gets crossed. Readings are pulled from EPA AirNow and this project’s own pipeline.
That interactive air quality map is where to check AQI near me, on the national AQI map or under its PM2.5 map layer. An hourly forecast, and the longer air quality forecast past it, cover the days ahead.
What actually triggers it
An alert fires when a tracked city crosses the number set for it. Nothing runs on a fixed schedule. Nothing arrives because a day was quiet. Track more than one city — work, family, travel, whatever crosses more than one place. Each city keeps its own threshold. No promised delivery window, no subscriber count to advertise — just a trigger tied to the number someone picked.
Why this matters more than it sounds
An alert closes the gap between buying mid-emergency and buying ahead. One r/AirPurifiers shopper, November 2024, bought an air purifier with the air already stinging and the store’s selection picked over. A r/Portland poster, months ahead in March 2023, urged buying “now instead of waiting until July and panicking because they’re all sold out.”
An alert is the gap between those two people. One bought at the worst possible moment. The other already knew.
Signup checklist
- Threshold crossings for the cities picked, at the number set. Nothing else.
- No address gets sold or rented to anyone.
- One click to unsubscribe. No account, no phone call, no form.
Data-handling detail lives on the privacy page, not repeated here. Find a city on the state-grouped index, or check what each AQI band means on the scale decoder first.