> ## Documentation Index > Fetch the complete documentation index at: https://aisa.one/docs/llms.txt > Use this file to discover all available pages before exploring further. # Historical Weather (ERA5 Archive) > Historical reanalysis weather for any coordinate, with data back to 1940. Retrieve historical reanalysis weather (ERA5 / ERA5-Land and related models) for any coordinate. `start_date` and `end_date` (both `yyyy-mm-dd`) are **required** and define the interval; data is available from 1940 to the near-present. Request fields with `hourly` and/or `daily` variable lists, and set `timezone` to localize daily aggregates. The response returns the resolved grid-cell metadata and `hourly`/`daily` blocks, each with a `time` array, one array per variable, and a matching `*_units` object. Example: `GET /apis/v1/openmeteo/archive?latitude=52.52&longitude=13.41&start_date=2022-01-01&end_date=2022-12-31&hourly=temperature_2m,precipitation&daily=temperature_2m_max,temperature_2m_min&timezone=Europe/Berlin`. **Billing: \$0.00015 per call (150 micros USD), metered per request.** All Open-Meteo endpoints are GET pass-through — authenticate with your AIsa API key as a bearer token (the same key used across every AIsa `/apis/*` endpoint); AIsa handles provider access. ## OpenAPI ````yaml openapi/openmeteo.json GET /openmeteo/archive openapi: 3.0.3 info: title: Open-Meteo Weather API version: 1.0.0 description: >- Open-Meteo weather data routed through the AIsa gateway: forecast, historical, air quality, marine, ensemble, seasonal, climate, flood, geocoding and elevation. All endpoints are GET pass-through to Open-Meteo (open-meteo.com); AIsa handles provider access. Flat pricing of $0.00015 per call (150 micros USD), metered per request. servers: - url: https://api.aisa.one/apis/v1 security: - BearerAuth: [] paths: /openmeteo/archive: get: summary: Historical Weather (ERA5 Archive) description: >- Historical reanalysis weather (ERA5 / ERA5-Land and related models) for any coordinate, with data back to 1940. `start_date` and `end_date` are required. GET pass-through to `https://archive-api.open-meteo.com/v1/archive`. Billed $0.00015 per call, metered per request. operationId: get_openmeteo_archive parameters: - name: latitude in: query required: true description: >- WGS84 latitude of the location. Multiple coordinates can be comma-separated. schema: type: string example: '52.52' - name: longitude in: query required: true description: >- WGS84 longitude of the location (negative for the Americas). Multiple coordinates can be comma-separated. schema: type: string example: '13.41' - name: start_date in: query required: true description: Start of the interval, `yyyy-mm-dd` (ISO 8601). schema: type: string example: '2024-01-01' format: date - name: end_date in: query required: true description: End of the interval, `yyyy-mm-dd` (ISO 8601). schema: type: string example: '2024-01-07' format: date - name: hourly in: query required: false description: >- Comma-separated list of hourly variables to return. Common values: `temperature_2m`, `relative_humidity_2m`, `dew_point_2m`, `apparent_temperature`, `precipitation`, `rain`, `showers`, `snowfall`, `weather_code`, `pressure_msl`, `cloud_cover`, `wind_speed_10m`, `wind_direction_10m`, `wind_gusts_10m`, `shortwave_radiation`, `visibility`. Also includes soil temperature/moisture variables. schema: type: string example: temperature_2m,precipitation - name: daily in: query required: false description: >- Comma-separated list of daily aggregation variables to return. Requires `timezone`. Common values: `temperature_2m_max`, `temperature_2m_min`, `temperature_2m_mean`, `precipitation_sum`, `rain_sum`, `snowfall_sum`, `weather_code`, `sunrise`, `sunset`, `sunshine_duration`, `wind_speed_10m_max`, `uv_index_max`. schema: type: string example: temperature_2m_max,temperature_2m_min,precipitation_sum - name: elevation in: query required: false description: Manual elevation (meters). Defaults to a 90m DEM. schema: type: string example: '38' - name: temperature_unit in: query required: false description: Temperature unit. Default `celsius`. schema: type: string enum: - celsius - fahrenheit default: celsius - name: wind_speed_unit in: query required: false description: Wind speed unit. Default `kmh`. schema: type: string enum: - kmh - ms - mph - kn default: kmh - name: precipitation_unit in: query required: false description: Precipitation unit. Default `mm`. schema: type: string enum: - mm - inch default: mm - name: timeformat in: query required: false description: Time output format. Default `iso8601`. schema: type: string enum: - iso8601 - unixtime default: iso8601 - name: models in: query required: false description: >- Comma-separated reanalysis models, e.g. `era5`, `era5_land`, `ecmwf_ifs`, `cerra`. Default best match. schema: type: string example: era5 - name: timezone in: query required: false description: >- IANA time zone name (e.g. `Europe/Berlin`) or `auto` to resolve from coordinates. Defaults to `GMT`. schema: type: string example: Europe/Berlin - name: cell_selection in: query required: false description: Grid-cell preference for the coordinate. Default `land`. schema: type: string enum: - land - sea - nearest default: land responses: '200': description: Historical weather for the interval. content: application/json: schema: type: object example: latitude: 52.5 longitude: 13.4 generationtime_ms: 1.2 utc_offset_seconds: 3600 timezone: Europe/Berlin elevation: 38 hourly_units: time: iso8601 temperature_2m: °C precipitation: mm hourly: time: - 2022-01-01T00:00 - 2022-01-01T01:00 temperature_2m: - 3.1 - 2.8 precipitation: - 0 - 0 daily_units: time: iso8601 temperature_2m_max: °C temperature_2m_min: °C precipitation_sum: mm daily: time: - '2022-01-01' temperature_2m_max: - 4.5 temperature_2m_min: - 1.2 precipitation_sum: - 0.6 components: securitySchemes: BearerAuth: type: http scheme: bearer bearerFormat: AISA API Key ````