After entering via reception, the amazing floor to roof atrium, we first went to the Library (open to the public with an appointment).  Displays of various old and important instruments, eg clockwork driven recording barometers and the original instrument that first measured the "ozone hole" over the Antarctic caused by CFCs (eg hair sprays, and leaking/scrapped fridges and freezers, etc).  Rows of racks of historical documents including weather reports from all over the UK and elsewhere ‑ it was 54°F, partial cloud and a SE breeze on the day I was born.

Next we went to see their 2 supercomputers ... or at least peer through the door at the grey boxes.  At the first supercomputer we could see a long grey box that stored all the metrological data used for weather forecasting, climate prediction and research (24 Petabytes or a Giga of Gigabytes – an awful lot of SIM cards).  The other is in a different room and offset from the first so a plane using Exeter Airport wouldn't hit both if it crashed on the building.  Those boxes have purple lights on them.  Both rooms have the same equipment; we just saw a different aspect of the boxes.  They also have a third supercomputer in the Science Park the other side of the M5.

Next we visited the Research Workshop which maintains and builds instruments.  We saw a new pair of modules, each the size of a large tea trolley, with a long foot-wide tube sticking out of one module for measuring "nucleation centres".  All clouds,  rain and snow starts with water accumulating around "nucleation centres" such as dust particles, bits of insects, volcanic ash, ice crystals, etc to form clouds.  This instrument, basically a tube acting as a fridge, with a laser scanner at the bottom, determines if it's dust ,ash, etc and how many of them and their size.  It's to be flown on their Cessna research plane later this year.  A previous mission over Iceland in winter showed the clouds were mostly forming round water droplets and not ice crystals as expected.  So this new instrument should improve our understanding of why and how clouds form.  Obviously it's critical to weather and climate forecasting.

Finally we went outside to the enclosure where they develop, test and calibrate instruments such as sunshine and total radiation recorders, and wind speed/direction meters, etc.  It sounds pretty basic but these ones are digital, so can be read remotely, and with no moving parts to go wrong in harsh conditions.  They also want each instrument to give the identical readings to the others – eg to 1/100th of a degree or better. The Met Office's supercomputers use as much electricity as the rest of Exeter.  So they have at the back of the Met Office a plant to recover the heat from them and use it to provide air conditioning, heating and hot water for the site.  As the enclosure is right next door they can't use it's measurements for weather forecasting – "unseasonably warm".