Lightning Fast Alerts

By Jordan H. Ferenz

Elevator Pitch

It sounded like a simple task - alert clients about lighting strikes. But then the product requirements arrived… This is the story of how we created a highly customizable, resilient, and scalable lighting alert system. Oh, and it’s blazing fast! Clocking in under 30ms.


Lightning is an extraordinary phenomenon of naturally occurring electrostatic discharge. It is very photogenic but can be very dangerous.

ClimaCell set its mission to help people and organizations manage weather-related challenges with the best information and insights. Unfortunately, it’s very difficult to forecast lightning strikes. Therefore, ClimaCell chose to alert about approaching lighting storms.

Clients can define locations to be alerted on, and buffers (radiuses) for identifying approaching flashes of lightning (either C2g or C2C or both). After a configurable amount of time without any lightning flashes in a certain buffer - an all-clear message is sent. Alerts are sent to recipient groups in whichever medium each recipient prefers: SMS, email, Slack, WhatsApp, or webhook.

This talk will describe how we built a resilient, customizable, and fast lightning alert system to provide accurate, relevant, and direct lightning alerts at scale. The new system is built of six orthogonal services running asynchronously to keep latency as short as possible. Processing time gets as low as 30ms.