# SYNTHORA Historical Weather

> SYNTHORA Historical Weather is a paid API for AI agents from api.hergertsynthora.com, paid per call via x402, $0.03/call, status unknown (last checked 2026-09-15).

Returns verified historical weather data (tmax, tmin, precipitation, max wind) for any location and date from 1940 to ~5 days ago using ERA5 reanalysis data.

## Facts

- Endpoint: POST https://api.hergertsynthora.com/v1/historical-weather
- Price: $0.03/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synthora-historical-weather-5ba33a4d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_68Ti42jc6Ea8U7fsdQU7B

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability synthora-historical-weather-5ba33a4d -d '<json body>'
```

Example prompt: What were the daily high and low temperatures, precipitation, and max wind speed in New Orleans on August 29, 2005? I need verified ERA5 historical weather data for that specific date and location.

## When to prefer this

Use this endpoint when you need verified, ERA5-quality historical weather data for any global location going back to 1940, especially for climate-market backtesting, insurance claim verification, or any application requiring authoritative reanalysis data rather than station-based or modeled forecasts.

## Known failure modes

- Date out of supported range (pre-1940 or within last ~5 days) returns an error
- Ambiguous or unresolvable location string may return an error or incorrect geocoding
- Malformed input string causes a parse failure
- Network timeout or upstream Open-Meteo archive unavailability
- Payment failure via x402 protocol blocks the request

## How this service works

SYNTHORA historical-weather: verified historical weather for any place and date (1940 → ~5 days ago) from the ERA5 reanalysis — tmax/tmin, precipitation, max wind. For climate-market backtesting and claim verification. Source: open-meteo archive, free, no key. $0.005 USDC x402 Base.

## Output

Returns ERA5-sourced historical weather metrics for the specified location and date, including daily maximum temperature, minimum temperature, total precipitation, and maximum wind speed, sourced from the Open-Meteo archive.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "input": {
   "type": "string",
   "description": "SYNTHORA historical-weather: verified historical weather for any place and date (1940 → ~5 days ago) from the ERA5 reanalysis — tmax/tmin, precipitation, max wind. For climate-market backtesting and c"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synthora-historical-weather-5ba33a4d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.hergertsynthora.com](https://www.zero.xyz/host/api.hergertsynthora.com/llms.txt)