> ## 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.

# Seasonal Forecast

> Long-range seasonal forecast (ECMWF SEAS5) out to roughly six months (about 183 days ahead).

Fetch a long-range seasonal forecast (ECMWF SEAS5 / EC46) for a coordinate. Request `daily` aggregates (e.g. `temperature_2m_max`, `temperature_2m_min`, `precipitation_sum`) and/or `six_hourly` steps (e.g. `temperature_2m`, `precipitation`); interpolated `hourly` variables are also available. Extend the window with `forecast_days`.

The response returns grid-cell metadata and the requested `daily`/`six_hourly`/`hourly` blocks, each with a `time` array, one array per variable, and a matching `*_units` object.

Example: `GET /apis/v1/openmeteo/seasonal?latitude=52.52&longitude=13.41&daily=temperature_2m_max,temperature_2m_min,precipitation_sum&six_hourly=temperature_2m,precipitation&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/seasonal
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/seasonal:
    get:
      summary: Seasonal Forecast
      description: >-
        Long-range seasonal forecast (ECMWF SEAS5 / EC46) out to roughly six
        months (about 183 days ahead), delivered as daily aggregates and
        6-hourly steps. GET pass-through to
        `https://seasonal-api.open-meteo.com/v1/seasonal`.


        Billed $0.00015 per call, metered per request.
      operationId: get_openmeteo_seasonal
      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: six_hourly
          in: query
          required: false
          description: >-
            Comma-separated 6-hourly variables. Common values: `temperature_2m`,
            `precipitation`, `wind_speed_10m`, `weather_code`.
          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: hourly
          in: query
          required: false
          description: >-
            Comma-separated list of hourly variables to return. Interpolated
            hourly variables (optional). 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`.
          schema:
            type: string
            example: temperature_2m
        - name: forecast_days
          in: query
          required: false
          description: Number of forecast days to return (0-274). Default 0.
          schema:
            type: integer
            default: 0
            example: 7
        - name: past_days
          in: query
          required: false
          description: Number of past days to include (0-92). Default 0.
          schema:
            type: integer
            default: 0
        - name: start_date
          in: query
          required: false
          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: false
          description: End of the interval, `yyyy-mm-dd` (ISO 8601).
          schema:
            type: string
            example: '2024-01-07'
            format: date
        - 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: 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: Seasonal forecast for the coordinate.
          content:
            application/json:
              schema:
                type: object
              example:
                latitude: 52.5
                longitude: 13.4
                generationtime_ms: 1.5
                utc_offset_seconds: 0
                timezone: GMT
                daily_units:
                  time: iso8601
                  temperature_2m_max: °C
                  precipitation_sum: mm
                daily:
                  time:
                    - '2024-01-01'
                  temperature_2m_max:
                    - 4.5
                  temperature_2m_min:
                    - 1.1
                  precipitation_sum:
                    - 0.3
components:
  securitySchemes:
    BearerAuth:
      type: http
      scheme: bearer
      bearerFormat: AISA API Key

````