A home assistant sensor that uses the OpenWeatherMap API to return:
- Up to 30 days of history data (rain, snow, min temp, max temp)
- 7 days of forecast (pop, rain, snow, humidity, min temp, max temp)
- Current observations (rain, snow, humidity, current temp, current pressure, wind, UVI, dew point)
- Aggregate daily data by date (precipitation, min temp, max temp, date)
- Status information (remaining backlog to load, current days API count)
- Creates a weather entity exposing captured data for use in a weather card.
Any number of sensors can be created using templates.
While HA recommends using individual sensors, you can assign additional attributes to a sensor.
The data is in 24 hour time slots, not date based, but data for the preceeding 24hrs.
Two API calls are used each hour, one to collect the new history data and another to collect the forecast and current observations.
When a new locations is created:
- Two API calls are made to collect the current observations and the last hour.
- Every refresh cycle (defaults to 10 min) 24 calls (1 day) will be made to load the history data (default 5 days) until the API limit (default 500) has been reached or all data has been provisioned.
You can configure the retention of the data so while you may choose to backload 5 days you can keep up to 30 days of data. This will be accumulated until the limit is reached.
This integration was initially built to support the Irrigation Program custom component and can be used to:
- alter the watering time/volume
- alter the watering frequency
You need an API key, which is free, but requires a registration. You do need to provide a payment method, however, the first 1000 calls are free and you can set an upper limit of calls. Setting this to 1000 will prevent you incurring any costs.
Note If you have an existing key you will still need to subscribe to the One Call 3.0 API, follow the instructions above.
HACS installation OpenWeatherMap History is available via HACS.
Search for openweathermaphistory, click on it and click the download button. Restart Home Assistant.
- Define the program using the UI. From Setting, Devices & Services choose 'ADD INTEGRATION'. Search for OpenWeatherMap History.
- Add the integration multiple times if you want more than one location. The second location must be at least 1000m away from any previously configured location to prevent accidental creation of 'duplicate' weather monitoring. Be aware that the API limit is for each location. Locations are not aware of API usage by any other location configured.
Easily define sensors using the bulk sensor option.
| Key | Type | Optional | Description | Default |
|---|---|---|---|---|
| Location Name | string | Required | Instance identifier, cannot be modified | Home Assistant configured name |
| API Key | string | Required | OpenWeatherMap API key | |
| Location | location | Required | Select from the map, cannot be within 1000m of an already configured location | Home Assistant configure location |
| Days to keep data | integer | Required | Retention period of the captured data. Can be longer than initial download. Data will accumulate as collected until the limit is reached. Will default to backload days it is defined with a value less thant the backload days | 5 days |
| Days to backload | integer | Required | Days for initial population, can be increased after the initial load, a new backload will commence | 5 days |
| Max API calls per day | integer | Required | The daily API limit, the count is for one integration, if you have two instances with 500 then each can use 500 api calls | 500 |
| Key | Type | Optional | Description | Default |
|---|---|---|---|---|
| Sensor name | string | Required | Sensor name, modify using HA once created | |
| Jinja2 Template | template | Required | A valid template that will define the sensor | |
| Attributes to expose | string | Optional | A comma seperated list of valid variables to add as attributes to the sensor | |
| Sensor Type | string | Optional | Select the type to define unit of measure. A template that returns a text value must be set to None | None |
All data is captured in metric measurements.
To ensure that you see the information in your local unit of measure:
- Ensure you select the appropriate 'Type of sensor'. This will allow HA to display information in the unit of measure defined for your instance.
- If you change the type of sensor you will see warnings in the log as the unit of measure will be inconsistent, go to the developers tools/statistics page to fix the issue.
WARNING (Recorder) [homeassistant.components.sensor.recorder] The unit of sensor.current_temp (°C) cannot be converted ...
Go to https://my.home-assistant.io/redirect/developer_statistics to fix this
- You can change the unit of measure (°C to °F) for each sensor in the sensor settings.
Unit of measure is not applied to attributes only to the sensor state. Attribute values are supplied as metric values
day0rain, day1rain, day2rain, day3rain, day4rain, day0max, day1max, day2max, day3max, day4max, day0min, day1min, day2min, day3min, day4min
Calculations are performed in the native unit of measure, so all calculations are in mm, mm/hr, °C, hPa, %.
Determine the watering frequency based on temperature
{% set avgtemp = (forecast1max + forecast2max + forecast3max)/3 -%}
{% if avgtemp < 10 -%}
Off
{% elif avgtemp < 20 -%}
Mon, Fri
{% else -%}
Mon, Thu, Sat
{% endif -%}
Display current temperature
{{current_temp}}
Version 1 factor, verifying to an expected 10mm rainfall. The resulting factor can be used to reduce the watering time or volume when there has been some rain but not enough to not water at all. This example could be extended to include temperature and increase the watering if it is hotter than expected.
{% set target_water = 10 %}
{# --- Equivalent Rain, past days rain have incrementally less impact --- #}
{% set equivalent_rain = day0rain + day1rain*0.5 + day2rain*0.25 + day3rain*0.12 + day4rain*0.06 %}
{# --- (target_water - equivalent_rain)/target_water --- #}
{% set adjustment = (target_water - equivalent_rain)/target_water %}
{# make 0 if negative #}
{% set adjustment_factor = [adjustment,0]|max %}
{{ adjustment_factor }}
Factor utilising forecast rain and probability of precipitation
{% set target_water = 10 %}
{# --- Equivalent Rain, past days rain have incrementally less impact --- #}
{% set equivalent_rain = day0rain + day1rain*0.5 + day2rain*0.25 + forecast1rain*forecast1pop*0.5 + forecast2rain*forecast2pop*0.25 %}
{# --- (target_water - equivalent_rain)/target_water --- #}
{% set adjustment = (target_water - equivalent_rain)/target_water %}
{# make 0 if negative #}
{% set adjustment_factor = [adjustment,0]|max %}
{{ adjustment_factor }}
A common usecase is to show daily/monthly rainfall. Using the cumulative data elements this can be achieved with the Utility Meter sensor
| Variable | example | Description |
|---|---|---|
| aggregate{i}date | aggregate0date | the date of the dataset |
| aggregate{i}precipitation | aggregate1precipitation | Rain + Snow |
| aggregate{i}max | Maximum temperature in the 24 hour period | |
| aggregate{i}min | Minimum temperature in the 24 hour period |
| Variable | example | Description |
|---|---|---|
| day{i}rain | day0rain | Rainfall in the 24 hour period |
| day{i}snow | day1snow | Snow in the 25-48 hour period |
| day{i}max | Maximum temperature in the 24 hour period | |
| day{i}min | Minimum temperature in the 24 hour period |
| Variable | example | Description |
|---|---|---|
| forecast{i}pop | forecast0pop | Probobility of precipitation in the 24 hour period |
| forecast{i}rain | forecast1rain | Forecast rain in the 25-48 hour period |
| forecast{i}snow | Forecast snow in the 24 hour period | |
| forecast{i}humidity | Average humidity | |
| forecast{i}max | Maximum temperature in the 24 hour period | |
| forecast{i}min | Minimum temperature in the 24 hour period | |
| forecast{i}wind_deg | Wind direction | |
| forecast{i}wind_speed | Winf speed | |
| forecast{i}UVI | UV index | |
| forecast{i}clouds | Cloud coverage | |
| forecast{i}description | Weather description |
| Variable | Description |
|---|---|
| current_rain | Current hours rainfall |
| current_snow | Current hours snow |
| current_humidity | Current hours humidity |
| current_temp | Current hours temperature |
| current_pressure | Current hours pressure |
| current_wind_deg | Wind direction |
| current_wind_speed | Winf speed |
| current_UVI | UV index |
| current_clouds | Cloud coverage |
| current_description | Weather description |
| current_dew_point | Dew Point |
| Variable | Description |
|---|---|
| hourly_time | Time axis for plotty |
| hourly_rain | Rainfall axis |
| hourly_snow | Snow axis |
| hourly_temp | Temperature axis |
| hourly_clouds | Cloud Coverage axis |
| hourly_pressure | Pressure axis |
| hourly_humidity | Humidity axis |
| hourly_wind_speed | Wind Speed axis |
| hourly_uvi | Rainfall UV index |
| Variable | Description |
|---|---|
| remaining_backlog | Hours of data remaining to be gathered |
| daily_count | Number of API calls for all instances of the integration, resets midnight GMT. This will not always match between instance of the integration due to the update frequency |
Tristan created a German language video about this integration: https://youtu.be/cXtVMJZU_ho
##V2026.05.03
- Add translation, AI generated
- Add additional pre defined sensors on the bulk sensor menu
- Frost Sensor
- Forecast and history based adjustment sensors
- Updated documentation of available attributes
- add weather entity to utilise data already captured
- add tests
- Add wind direction, wind speed, UVI, clouds and description to Current observations and forecast data.
- Sensor processing to ensure deleted sensors are correctly removed from HA when removed from configuration.
Add aggregate day data, data for a calendar day (uses an additional 24 call per day) Action to run each of the 4 calls available through the onecall API
- API details and result displayed to Notifications Action to list available attributes and values to Notifications Delay the collection of data until 5 minutes after the hour.
- This is to allow corrections to be applied prior to gathering the data as there are some collection stations that are reporting incorrect precipitation readings that are corrected within a few minutes
- Add attribute to store list of times and rain, can be used to graph the data using 'plotty' a custom card.
- correct bulk creation of sensors
- Fix issue with index out of sequence when updating sensors.
- Add new feature to auto create sensors. Currently accessed from the API page.
- Modify Naming of sensors to support multiple instances more transparently
- Clear entity registry of unused sensors (no more unavailable sensors)
- Fix issue with index out of sequence when updating sensors.
- Add new feature to auto create sensors. Currently accessed from the API page.
- If you recently downloaded this Prior to 19th September 6pm AustralianEST you will need to redownload (only 10 downloads impacted)
- Some improved performance
- Handle data/option mismatch on upgrading
- change from pickle for persisted data to using HomeAssistant Store, DATA RELOAD REQUIRED existing data will not be carried over to the new data structure
- restrucure of data storage
- remove store resources when removing the configuration
- Reduce impact on startup of HA## V2.0.13
- add 'pyowm' to dependencies.
- Add api_call service to list available attribut
- Deploy custom card with the component, no need to install seperately, please uninstall the old version
- Round attributes to 2 decimal places
- Performance fixes
- Add api_call service to support testing/debugging
- Add better tests for API version
- Improve messaging for API issues
- Add cummulative rain and snow to support meter sensor
- fix issue with sensor class 'none'
- correct where some numerics are recognised as string preventing modification of the display precision
- Handle API call failure more gracefully
- Accumulate API call counts across multiple instances
- Fix strings.json and en.json for selectors
- fix daily API count reset
- Accumulate API count across all instance of the integration
- Fix issue 18 - Max days can be less than backload days
- Fix issue 15 - Daily API count not resetting
- Fix issue 16 - Sensor Type not included in translation
- Add current observation and forecast information
- Support the collection of more than 5 days of data
- Monitor API usage
- Move to config flow for configuration
- Each attribute can be exposed as a sensor
- Sensors are defined by Jinja templates
- Initial Release.