Show HN: I built a Red Flag Warning zone-check tool for the East Bay in 48h
redflag-check.infoHey HN. I'm a high schooler in Fremont, CA. Tuesday morning I got a county-wide AC Alert text telling everyone in Alameda County to prepare a go-bag for an East Bay Hills Red Flag Warning that starts tonight at 11 PM. The text went to ~half a million phones.
The actual NWS warning polygon only covers East Bay Hills (NWS zone CAZ515). Most people who got the text don't need a go-bag tonight. Some in the hills don't realize how close they are. So I built this tool - https://redflag-check.info/ mit licensed public github - https://github.com/vedant-f-is-ma/redflag-check
It does a few things - tells people if they are in the flagged zone, and also provides a way to check if a buddy is in flagged zone and send them a text. Everything without installing an app.
I heard back from Oakland Firesafe Council director about a gap in my understanding (and the tool). To my surprise, and through feedback, I realized that you cannot assume that only the flagged area is at risk. Adjacent areas are at risk too! Fires do not follow zone boundaries! I fixed the tool.
I built this in 48 hours to close that specific gap: type your address, get a yes/no on whether the NWS polygon covers it, your Genasys evacuation zone, tonight's wind + humidity at your point, a plain-English action checklist, a per-school decision view for East Bay districts, and a one-tap iMessage buddy-check template for a hill-neighbor at 10:30 PM. Cool. You may want to explain what a Red Flag Warning is and some general details about what that means if you are in a red flag warning zone or not. I lived in the Bay Area for a while and didn't know. It would also be cool if for entering the address it did autocomplete with valid addresses. sure, so red flag warning is sort of high fire risk condition, not to evacuate but to get people ready just in case. generally they monitor things like winds, humidity, and something that they call dry fuel (actually a firefighter explained this to me as something fairly critical but no certain way to tell). when the conditions are sort of amenable to creating a fire, they flag the risk with a red flag warning so if you are in the zone some prep helps, keeping phone charged, car keys handy ... autocomplete sounds fun, i'll try I read up more - the 91 Oakland hill fire started small in one zone and pushed outside the initial zone into populated areas, so did the 23 lahaina, started inland burnt the whole town and it actually went crazy claiming over 100 lives. 25 palisades is more recent and rode the 100mph winds feels silly that I did not realize that fires do not have zone boundaries, and warnings to adjacent areas are a deliberate choice. no one knows which way the wind blows. so glad it got called by the fire expert