Micro / Minor
Alerts within 100 miles of the epicenter. These are often felt locally but rarely cause damage.
ALERT RADIUS BY MAGNITUDE
Bigger quake, wider alert radius.
Alert radius scales automatically with magnitude — small local tremors stay local, major quakes go nationwide.
Minor to Light
Alerts within 150–300 miles. Felt by many people, may cause minor damage near the epicenter.
Moderate to Strong
Alerts within 500–1,000 miles. Capable of causing significant damage to poorly constructed buildings.
Major to Great
Alerts sent nationwide. These are serious seismic events that cause widespread damage and can trigger tsunamis.
How It Works
1
USGS Records the Quake
The US Geological Survey operates a nationwide seismic network. Within minutes of a quake, USGS publishes data including magnitude, location, and depth.
2
StormCast Checks Every 10 Minutes
Our server polls the USGS GeoJSON feed every 10 minutes. New quakes are matched against each device's GPS location using the Haversine distance formula.
3
You're Notified Once
If you're within the alert radius, you receive one push notification. You'll see the magnitude, a plain-English description (Minor, Light, Moderate…), the reported location, and how far away it was.
Frequently Asked Questions
What magnitude earthquakes does StormCast alert for?
StormCast monitors USGS for all earthquakes M2.5 and above. The alert radius scales with magnitude so smaller quakes only alert people nearby, and major quakes alert everyone.
How fast does StormCast send earthquake alerts?
StormCast checks the USGS feed every 10 minutes. Alerts typically arrive within 10–20 minutes of the earthquake being recorded — faster than most news alerts.
Will I get duplicate alerts for the same earthquake?
No. Each USGS earthquake ID is tracked in our database. You'll only receive one notification per quake, even if it's updated by USGS after initial publication.
Does it cover earthquakes worldwide?
Yes. The USGS GeoJSON feed includes global seismicity. Major quakes anywhere in the world will be detected — and if you're within the magnitude-scaled radius, you'll be notified.
Can I use this if I live in an earthquake-prone area?
Absolutely — StormCast works well in California, the Pacific Northwest, Alaska, Oklahoma, and anywhere else earthquakes are a regular concern. Your location is used automatically.