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  1. PS. I suppose it depends whether you want the maximum of the day and the minimum of the night, or the max/mins of a day.
  2. The Met Office don't seem to use the 'official' method for the 'day's extremes' pages on their website, as on there, they define the time ranges as: Highest maximum temperature - (0900 to 2100 on the date shown); Lowest minimum temperature - (2100 on the previous day to 0900 on the date shown) I've been playing around with some of my weather data recently and have been using these ranges, but the problem is that on the rare occasion a maximum occurs during the night, it gets missed. On the other hand, using 0000-0000 or 0900-0900 seems to have its drawbacks too.
  3. Hi Are there standard time ranges for maximum and minimum temperatures? I believe the data through Ogimet takes the max as being the max between 6am and 6pm, with the min being between 6pm and 6am (the following day). However I'd have thought that could miss some minimums in the winter when often the minimum is just before sunrise at nearer 8am? Would 9am - 9pm for max and 9pm - 9am for min be better, or even 6am - 9pm for max and 6pm - 9am for min?
  4. The WeatherPro app has a 'Feels Like' temperature and I was wondering what formula they use to calculate it. I've found various formulas online, including one used by the Calculus software, but they produce lower results compared to the WeatherPro one. For example, with a temp of 28C, wind speed of 12mph and humidity of 44%, WeatherPro has a 'feels like' temp of 31C, but the formulas I found come out at around 29C. Does anyone know which is the most accurate formula? Preferably one that can be used at all temperatures. Thanks!
  5. Thanks, that's interesting - I'd also wondered whether there was too much 'mass' in the screen which was contributing to overheating. However, I painted the inside white and this, along with the fan running in the sunniest conditions, seems to have removed the spikes when the sun is out. The temperatures I record are very close - almost identical sometimes - to the local MetO stations (and closer than other unofficial stations). For those interested, I used the 1937 Met Office Stevenson screen spec (and used option #4 for sheathed instruments) and slightly scaled down the measurements. I think the link was originally posted here ages ago but I've re-uploaded it - https://www.dropbox.com/s/8tmm78to11a4pdk/Met Office Stevenson screen.pdf?dl=0 I also created a SketchUp model which I'll post a link to as well.
  6. Thanks for reply. I've attached pics of my screen - it's about 25x25x25cm in size. I've not yet painted the inside, but I have fitted a fan at the (north-facing) back, which blows air from outside to the inside. I think it's helped and the screen seems to perform better than my old screen, but the readings are still a bit 'spiky' when the sun comes out. Anyone got any further advice? Thanks!
  7. Hi What inside colour would people recommend for a small, wooden, double-louvred aspirated Stevenson's screen? I've read black is best as it'd prevent any light being reflected onto the sensors, but I'm worried the black surface would store heat. Also, should the fan (for aspiration) blow air onto the sensor or away from it? Thanks
  8. As with previous years, predict when and where the first 20C of the year will be! I'll go for my home turf of Writtle and 24th March.
  9. First post-5pm sunset for me since the clocks went back will be coming this week!
  10. Thanks - do you know what the UK standards are called? I'll see if I can find them - would be interesting to see. It'd also be good to see any other examples of what's considered to be falling/rising etc. in terms of pressure.
  11. I've got a program on my weather station which uses a form of the old Zambretti forecaster to generate forecasts four times a day. It relies on wind speed/direction, current pressure, pressure trend and season. I've got it set so that for pressure trend it looks back over the last 4 hours and a change of >1.5mb is rising, <1.5mb is falling and in-between is steady. For wind, it looks at average speed and gusts over last 3 hours, with an average of less than 1.3mph considered to be "dead calm". My questions are: What pressure change, and over what period, would be considered to be falling/steady/rising? What average of wind speed/gusts over a few hours would be 'dead calm'? Literally 0? Or would 0.1 be considered to be registered as wind? Thanks in advance. Would be interested in people's opinions on this!
  12. List of maximum temp by year

    Thank you very much!
  13. A while ago, someone posted a link to a list of yearly maximum UK temps and the date they occurred. Does anyone have this link please? I've searched but to no avail! Thanks
  14. Hi Does anyone know where the temperature sensor (or thermistor?) is located in the transmitter module for the Fine Offset WH1080 weather station? See attached an image of its insides. I thought it may be the white square component but that's actually for humidity. Thanks!
  15. Is this the Winter of the future?

    Have you got a link to this please? Either the actual graphic or the topic of discussion on here. Had a quick Google but can't find it.