All I could find is this:
The L. G. Groves' Memorial Award for Meteorological Air Observers, of the approximate annual value of £12 10 shillings, will be confined to flying personnel who have been employed during the year on meteorological air observer duties and will be awarded for meritorious work or devotion to duty.
The link below has the same details as quoted by spike88:
LG Groves Memorial Prize - Prize winners