@KristerJohansson. According to your description, based on my understanding, this is an IoT solution in which a data collector receives weather data from some devices with sensors and stores this data for analysis and reporting. I think there are some key fundamentals that need to be considered as variables that determine the amount of data, such as meteorological columns, data format, sample rate, number of devices, etc.
Therefore, for scaling and big data, in my experience, as reference information, I believe that the best practice is to use IoTHub to process communications and use Stream analytics to extract and store data from IoTHub to Blob storage. After years of collecting data, you can use Azure Machine Learning to read this data from the blob for analysis and reporting.
Any concern, please feel free to let me know.
source share