So who would live in England, longest day-1, room lights on

Posted: June 24, 2013 by tchannon in weather


Weep for the poor dear PV brigade, went so dark I popped outside and noticed lights on instead of approaching 1kW/sqm and this the day before longest day of the year. Lowest moment 39W.

It was solid grey cloud, no rain, moderate wind which did a 180 degree pirouette during daylight from East through South to West, no change in wind speed.

Lidar and radar don’t tell much



I’ve not been able to find useful satellite images, nor radiosonde. Piecing together what I have gleaned we were in the middle of a mess of occluded fronts, cloud was probably stacked high, but infra-red satellite doesn’t show all cloud.

Lidar was being blocked by a dense low layer, radar shows not much cloud. I’m guessing here, I suspect there was very deep cloud but below the radar threshold for display. Given no rain I don’t see how a low cloud layer could stop that much light.

Quick scan through the plots, this year since 16th February there have been 19 reasonably sunny days, a handful really sunny.

Moderate temperature, fairly steady at 17C until the cloud cleared, then it plummeted.


  1. Tenuc says:

    Been same here, Tim, in (normally) Sunny Sussex. Seems like a time-warp back to the summers of yesteryear.

    This, along with cold, grey winters makes me long for the predicted English ‘Mediterranean Climate’ we were promised when global warming was first mooted.

  2. tchannon says:

    The good news is fairly good weather for the rest of the week but not hot.

    Bad news is their might be a touch of June frost tonight.

  3. Roger Andrews says:

    Here’s what we got at lat 20N long 103W.

    Incidentally, I quit living in England in 1964. 🙂

  4. tchannon says:

    So it’s you! You stole the sun, took it with you.

  5. Roger Andrews says:

    Sorry, but I needed it for the solar panels on the roof

  6. tchannon says:

    How about a time share?

  7. Richard111 says:

    Lovely sunny morning here in Milford Haven. Thermometer has just reached 7C. Brrr..

  8. Stephen Richards says:


    I’ll try to make you feel better. Here, in SW France we have higher average sunshine per year than the mediteranean coast AND it has been awful this year and yesterday was the same as many days before; gloomy, cloudy and a little damp. There I hope that works.

  9. Stephen Richards says:

    Incidently, anyone noted the recent steep rise in stratospheric temperature shown by satelite on Roy Spencer’s blog.

  10. Doug Proctor says:

    You show SI for sunny day June 8th @ about 905 W/m2. What is the % TOA TSI for this location (latitude) this time (13 days off solstice), this orbital position (26? days before aphelion) based on 1361.5 AVERAGE orbital TOA TSI?

    I can’t do the math, but I know the principle. With these three things we can know the TOA TSI for 8th June. With that – 8th June being (?) cloudless, we know the clear air absorption and refraction component (TOA TSI less measured SI). With a similar calculation for 21 June, we then know full cloud absorption plus reflection.

    A few such readings (and knowledge of specific TOA TSI) with cloud cover and (?) thicknesses, we could calculate reflectivity and absorption per thickness. (Though I suspect that thickness is not so important for reflection as reflection is high; if cloud cover is considered as a series of equal reflectivity layers, the amount of potential is very small within 4 layers; absorption is also minimal once the clouds are thick for the same reason).

  11. Bloke down the pub says:

    Weep for the poor dear PV brigade, went so dark I popped outside and noticed lights on instead of approaching 1kW/sqm and this the day before longest day of the year. Lowest moment 39W.

    To put a slightly different perspective on things, my pv system has already produced as much this June as of the 25th as it did for the whole of last June. When the Met office harp on about what weird weather we’re having, what they really mean is that it’s just average for the UK. If you don’t like it, do as Roger Andrews, move somewhere warmer.

  12. michael hart says:

    I also was out walking very late last night. By the time I got back inside I could see my breath condensing in the air. I had no gloves and was banging my fingers to try and warm them up.

    But more than once during the walk I also asked myself why anyone would wan’t to live anywhere else. 🙂 “Oh, to be in England, In the Summer time…”

  13. mkelly says:

    So 1361 – .3 is 953 W/m^2 times cos 28 is 841 W/m^2. Looks like you are getting approx. 64 W/m^2 more than you should. Rough numbers.

  14. tchannon says:

    Folks, there are great comments but I am not a good conversationalist or writer.

    I have a huge body of material to reveal about the history of atmospheric and solar measurement leading right up to current. The recent item about TSI was getting a side part of the story out so it can be linked in later.

    This will probably appear on my blog and crossed here as well, will get less lost over there.

    michael hart, was indeed chilly but we are fortunate plenty of humidity was up hence too much heat for a frost. Due dew.

    mkelly, lots of fun coming on this stuff. The lack of concrete information is hurting.

    bloke down the pub, fair comment. There has been plenty of broken sunshine so it adds up. Thin cloud probably makes little difference. Down here in this area of the south we have been getting a raw deal, it is a peculiarly cloudy area. Might be why Chilbolton cloud research was put there rather than sunny places.
    I’m not convinced by this (not inline image because owners are sniffy) where it might be that average hides large seasonal vagarities, it is not for cloud either.

    Stephen Richards, wait.

  15. […] Stephen Richards writes in a comment here “Incidently, anyone noted the recent steep rise in stratospheric temperature shown by […]

  16. oldbrew says:

    By 2015 Brits may not always have the option to turn the lights on, says Ofgem:
    ‘Spare electricity power production capacity could fall to 2% by 2015, increasing the risk of blackouts.’