I've been watching the temperature reading for the last hour or so and it looks like I can confirm that the high reading I saw yesterday is down to sunlight falling on the thermo/hygro transmitter. Here's the readings I've got so far this morning (comparing my Maplin unit and a local personal station with my WS3600 — note that I'll be updating this as the day goes on).
|Sun hits thermo/hygro transmitter|
|Sun no longer hits thermo/hygro transmitter|
Given this I really am going to need to try and find a better location (hard to do) or try and sort out some sort of extra screen.
File Under: Personal Weather Station, WS3600, Temperature Problems.