The temperature in the bedroom tracks the ambient far too well - when we had the hot spells in summer, it regularly went over 30°C, up to 34° or so on the hottest days - fortunately, there's a (small & noisy) air-conditioner in there, which managed to get the temperature back down to bearable after a couple of hours of running. Now we're having a cold spell, and the temperature in there was 16°C this morning. This house does have central heating, but it's not as effective as we'd like, due to the above mentioned tent-like insulation, and the design of the house - the lounge area has a double-height ceiling, and upstairs a balcony overlooking this space connects the bedrooms. This means that all the heat entering the lounge at ground level goes straight up and seemingly straight out of the house, making it quite hard to warm up the place.
So ... roll on June 30th.
 Glaswegians & other Scots reading this may now smirk, snicker, and laugh, as "cold spell" around here means maximums around 14-18°C with patchy rain - to be fair, though, we are the second stop for the Antarctic-chilled 40kt wind after Tasmania, so it feels rather cooler than that.