June 11, 2026
Hot maps, hotter takes
Show HN: I built a Red Flag Warning zone-check tool for the East Bay in 48h
A 48-hour fire warning helper has locals saying, ‘Wait... the danger zone isn’t a wall?’
TLDR: An East Bay maker built a free address-check tool in 48 hours to show who’s under a fire-weather warning and which evacuation zone they’re in. Commenters loved the idea but the big reaction was a sobering one: fires don’t stop at map lines, and the site should explain that clearly for everyday people.
A fast-built East Bay website that lets people type in an address and check whether a Red Flag Warning applies tonight has struck a nerve, because the comments quickly turned into a mini public-safety reality check. The tool pulls together weather alerts, evacuation zones, and simple what-to-do advice, and the maker even adds a blunt warning: these official shapes on a map are not magic borders that stop fire. That line hit hard.
The biggest reaction? A mix of praise and alarm. One commenter basically had a full-on revelation, pointing to the 1991 Oakland Hills fire and the deadly Lahaina disaster as proof that fires do not politely stay inside neat little warning areas. The mood was very much: “Oh wow, this is more serious than people think.” That gave the project a surprisingly emotional edge for a scrappy Show HN post.
But of course, the internet wasn’t going to let it stay purely wholesome. Another commenter jumped in with the classic usability drag: cool tool, but what even is a Red Flag Warning for regular people, and why doesn’t the address box help you out with autocomplete? Translation: useful idea, but don’t make stressed-out residents play guessing games with their street name. The low-key drama here is between urgency and polish: people love the mission, but they also want the site to hold panicked users by the hand. Even the funniest undertone had a grim edge: several reactions boiled down to the meme-worthy realization that fire does not care about your polygon.
Key Points
- •The article presents a free East Bay address-check tool for Red Flag Warning applicability, recommended actions, and evacuation zone lookup.
- •The tool requires no signup.
- •Its listed data sources are the National Weather Service, the US Census, and Genasys.
- •The article states that NWS Red Flag Warning polygons are advisory and should not be treated as hard fire boundaries.
- •It advises readers during fire season to keep a go-bag ready and treat fire-season nights as fire-weather nights regardless of polygon status.