Read states index into a new entity

Hoping someone can point me in the right direction!

I am using a custom weather card with forecasting, but it doesn’t support integrations that don’t include specific readings (templow). The data is delivered to HA formatted in a YAML index:

  - datetime: '2023-06-05T12:00:00+00:00'
    condition: sunny
    precipitation_probability: 0
    wind_bearing: NE
    temperature: 17
    wind_speed: 28.97
  - datetime: '2023-06-06T12:00:00+00:00'
    condition: sunny
    precipitation_probability: 1
    wind_bearing: NE
    temperature: 17
    wind_speed: 25.75

I basically want to take the above, read it, then insert it into a new entity, creating the missing templow value for each entry just using the temperature reading. I am able to read the temperatures from each entry with the following by incrementing the value for each day:

{{ state_attr('weather.met_office_LOCATION_daily', 'forecast')[0]['temperature'] }}

How can I transplant the temperature readings into a new entity and create new values (templow and temperature)?