Rainfall Data
Rainfall data is available for England for the past year from the Environment Agency API https://environment.data.gov.uk/flood-monitoring/doc/rainfall additionally hourly historic data is available on request. Hourly data stretching back to 2010 has been combined with daily updates for each rainfall station and is available to download by clicking the link.
ERA-5 reanalysis
The ERA-5 satellite network records a huge number of parameters. These are post processed (reanalysis) and compared with ground measurements and compiled for each 0.25° of latitude and longitude. Hourly data for each grid square can be downloaded by clicking the grid square.
NOAA met stations
The NOAA provide access to data from weather stations around the world. This can be accessed using the worldmet R package: