Every 10 years the Met Office updates its 30-year standard LTA data. The present 30-year standard is 1981-2010. These data are calculated for each square kilometre using their national grid-based model for the entire country. The following data are generated for each square:
maxtemp
meantemp
mintemp
grassmin
soiltemp30cm
airfrost
groundfrost
rainfall
raindays0.2mm
raindays1mm
raindays10mm
sunshine
snowfalling
snowlying
windspeed
These data are provided as monthly means, quarterly (seasonal) means, and annual means (ie 17 numbers per variable).
During our site visit to Eskdalemuir last month I asked about the availability of these data, and was told by Mike Stewart (MO, Edinburgh, mike.stewart (at) metoffice.gov.uk) that we had but to ask for them for our own sites. I duly requested them for my site and, true to his word, he has provided them.
So if anyone else would like the official LTA data for the square kilometre in which their site is located, write an email to Mike and I'm sure he will oblige.
Rob