Glastonbury Forecast 2010

[J10]

This is the last update before the festival starts. However I will still be doing forecasts for the remaining days, especially for the weekend, which is looking the part of the weekend which might be the most troublesome.

Wednesday

As previously mentioned a weak weather front is set to push in from the west, but higher pressure will mean it keeping dry over Glastonbury, and the cloud is not set to push in before the sun sets in the evening.

So a dry day, and mostly bright or sunny with temps reaching as high as 23-24c.

Thursday

The weak weather front will push south west during the day, bringing a lot more cloud overnight, for the morning and early afternoon. There may be small light drizzle during the morning, but really not amounting to that much. As the front clears away to the South East during later afternoon and early evening, some brighter or sunny spells should develop. Temps pegged back a little at 22-23c.

Friday

Pressure tend to build back up from the south, and this should settle things down again. A bright day is very likely with long sunny spells, but probably not unbroken sunshine. Temps might hit the 25c mark during the afternoon. So as previously warned, make certain you take your sun cream.

Wednesday to Friday Summary

Very high confidence of 3 essentially dry days, with warm temps and the only blot some cloud (and perhaps light drizzle) early Thursday, so very much on 1 on the Glasto meter.

Saturday

The general pattern is for the pressure to be around 1015mb, which is in not really dominant high pressure but also no area of low pressure, as such the weather is slightly in between. To start the day, the weather is looking promising, it should be dry and bright or sunny an quickly temps warming up.

However as per the charts below, CAPE levels rise with the chance of some thunderstorms, at the moment, Glastonbury is not a direct hit according to the CAPE charts, but they cannot be rule out at this stage. So a 15-20% chance of a thunderstorm in the afternoon or evening, with temps around 23-25c.

Sunday

In many ways Sunday is similar to that of Saturday, with no dominant weather pattern. Again is should be a dry and bright or sunny start, but temps quickly rising, and more quickly than on Saturday. However as per the charts below, CAPE levels rise and to more widespread across the UK compared to Saturday. There is a greater chance of a thunderstorm, probably around 25-30% of one hitting Glastonbury. It could be a scorcher on Sunday with temps possibly hitting 26-28c.

Weekend Summary Some hot sunny weather but an increasing chance of a thunderstorm over the weekend.

In conclusion, if you are setting off for the festival, enjoy it, take sun cream and an umbrella just in case for the weekend, and try to keep in touch both here and elsewhere for updates for the weekends weather.

[Fussy Onion]

Thank you!

Sunny clothes packed along with wellies and waterproofs as always.

[Neil the Macc lad]

Thanks for everything this year Jackone. As ever your forecasts are invaluable!

[gizmoman]

Thanks very much Jackone, your efforts are much appreciated, it's looking like it could possibly be my first totally dry one (on my 9th attempt!) though after 2005 the threat of thunderstorms is a worry!

[J10]

From relatively afar, it seems like a good start to Glastonbury, with a good deal of sunshine. So onwards for the rest of the festival.

Thursday

Cloud will increase during the early hours, as a weak weather front edges South East. Some patchy rain or light drizzle is just about possible tomorrow morning but really not amounting to that much. As the front clears away to the South East, it should turn steadily brighter and sunnier for the late afternoon and into the early evening. Temps pegged back a little at 22-23c, but feeling pleasant generally in light winds.

Friday

Pressure tends to build back up from the south, and this should settle things down again. A bright day is very likely with long sunny spells, but probably not unbroken sunshine with perhaps more cloud in the afternoon. Temps are likely to reach 23-24c mark during the afternoon.

Thursday to Friday Summary

Very high confidence of 2 essentially dry days, with warm temps and the only blot some cloud (and perhaps light drizzle) early Thursday, so very much on 1 on the Glasto meter.

Saturday

The general pattern is for the pressure to be around 1015mb, with no dominant pattern as was suggested yesterday. To start the day, the weather is looking promising, it should be dry and bright or sunny with temps rising very quickly.

However as per the charts below, CAPE levels rise with the chance of some thunderstorms, at the moment, Glastonbury is not a direct hit according to the CAPE charts, but they cannot be rules out at this stage. So a 15-20% chance of a thunderstorm in the afternoon or evening, with temps around 24-26c.

Sunday

Lower pressure seems to be advancing from the west, and although not really pushing that far east, it does increase the chance of a thunderstorm developing.

Again a dry start is likely with some decent sunny spells, but CAPE levels rise during the afternoon more generally covering Western areas, and with Glastonbury in a high risk area.

At this stage the chances of a thunderstorm is around 30-35%. Temps are set to rise to make a sultry day, and temps may reach 26-28c, especially if it stays sunny.

Weekend Summary Some hot sunny weather but an increasing chance of a thunderstorm over the weekend, with with Sunday the most likely day for a downpour.

[danbailey80]

Thanks again JACKONE... Sounds fine to me...Am I right in not being worried about these thunderstorms? If they do strike, are you thinking they would be heavy and dramatic but only for up to 10/ 15mins approx? Because if so, this won't do anything much and Glasto would be dry again in an hour or so..OR are we talking heavy for an hour plus..? Cheers again...

Edited June 23, 2010 by danbailey80

[J10]

Thanks again JACKONE... Sounds fine to me...Am I right in not being worried about these thunderstorms? If they do strike, are you thinking they would be heavy and dramatic but only for up to 10/ 15mins approx? Because if so, this won't do anything much and Glasto would be dry again in an hour or so..OR are we talking heavy for an hour plus..? Cheers again...

Impossible to tell, they are very difficult to pinpoint, a day ahead, let alone 4. Not need to get worried, but certainty worth keeping an eye on.

Also worth noting that Ian's blog on the BBC, has similar thoughts for the Sunday.

http://www.bbc.co.uk/blogs/weather/ianfergusson/

[J10]

This is the latest update, for the remaining 3 days of the festival.

Friday

For several days, this has looked a settled day, dry with long sunny spells and nothing has changed in the models with regard to this view.

Temps are likely to reach 23-24c mark during the afternoon, feeling very warm in light winds.

Saturday

Over the past couple of days, there has appeared to be a small risk of thunderstorm on Saturday. CAPE levels are set to rise, but this is largely restricted to Mid Wales and the West Midlands northwards, as such the risk of thunderstorms over Glastonbury has further diminished since yesterday to around 5-10%.

So to start the day, the weather is looking promising, it should be dry and bright or sunny with temps rising very quickly. Although a shower cannot be ruled, it should stay dry and bright or sunny. Temps reaching 25-26c.

Sunday

Lower pressure seems to be advancing from the west, and this is set to being frontal rain for North Western parts of the UK. There remains a chance of a thunderstorm, as shown by the CAPE charts below, however these seem more concentrated on SE England, so for a second day running, Glastonbury may escape. However there is still a greater chance of a thunderstorm on Sunday compared to Saturday, at around 20%.

A dry start is likely with some decent sunny spells, and this should continue into the afternoon, thunderstorm risk pending, Temps are set to rise to around 25-27c.

Weekend Summary Some hot sunny weather but with a slighlty diminishing chance a thunderstorm for the weekend, the risk mostly for the Sunday.

[J10]

Looking at the BBC report from Glastonbury earlier, it seems the weather there has been glorious today. Well what is likely for the weekend, will the sunshine and warm or hot weather continue or will the threatened thunderstorms hit.

Saturday

Over the past couple of days, there has been a diminishing risk of thunderstorms for Saturday, as the elevated CAPE levels have become concentrated in an areas to the West of the Midlands and fringing East Wales. There remains a very small risk of a thunderstorm on Saturday afternoon/evening at around 5-10%.

So a sunny start to the day is likely, and temperatures are set to rise sharply to reach around 26-27c by mid afternoon. A good deal of sunshine is expected also during the afternoon, so don't forget to put on sun cream. Temps reaching 25-27c.

Sunday

Lower pressure seems to be advancing from the west, and this is set to being frontal rain for North Western parts of the UK. However much of England and Wales is set to be bathed in glorious sunshine to start the day. Temps will rise sharply once again.

As a result CAPE levels will rise, but this is concentrated in South Eastern England, where the temps will be at the highest. However as per the GFS 12Hz below, CAPE levels are quite high in a area around Glastonbury. So a thunderstorm is possible, although unlikely, the risk is aorund 20%.

Overall Weekend Summary

Generally looking excellent over the weekend, and the odds are very much in favour of thunderstorms missing Glastonbury throughout the entire weekend, so enjoy these conditions, they don't happen that often around the Glastonbury festival.

[conor123]

Lucky sods, i wish i had gone this year

[J10]

Just had a quick look at the GFS for tonight, and it seems that the chance of a thunderstorm at Glastonbury has further diminished. It is looking hot and sunny with temps around 25-27c.

[stuboy]

Returned early this morning, and what can I say about the weather? I thought last year was good, but 2010 tops it all. Amazing.

Thanks Jackone as always for this thread, always an informative and very useful read!

[Jezzer]

Back at work after spending a wonderful time at Glastonbury, the weather was stunning, we couldn't have asked for any better.

Just glorious! Many thanks to JACK for the help over the last few weeks:clap:

[William of Walworth]

the weather was stunning, we couldn't have asked for any better.

Just glorious! Many thanks to JACK for the help over the last few weeks:clap:

Great weather summary Jezzer ...

All thanks to JACKONE duly seconded -- THANKYOU!

I have had next to no net access since very early on Sat 19th, and we only got back this afternoon (Tuesday 29th)

We had pretty much nothing else but very sunny, and very warm to hot weather throughout - there was some very light rain the night of Friday 18th, and some more, very light, showers the night of Monday 28th, by which time all the punters and a a good number of the crew had gone.

Otherwise, wall to wall blue skies and sunshine in the daytime, started off warm at the start of the week and became very hot by Saturday and Sunday. We were there 10 days with next to no rain, and none at all over he festival period proper, how rare is that?

The downside was that there were many many cases (well over 1000) of people suffering from heatstroke and dehydration, having to be treated by the site hospital or by the roving paramedics, who were stars. Also, not everyone remembered to use the suncream enough, the combination of lobster 'tan' and England shirt (up to 5 pm Sunday anyway!) was a high combination ... on the Info stalls where I worked, we often ran out of our free suncream which was heavily in demand -- but sometimes too late for the more cider challenged!.

Me, I was sensible though, and I now have niely brown arms, legs and face now, and a battered old straw hat was the daily necessity for me ...

Some of the nghts were warm enough to stay in shorts and a thin shirt til after midnight ... others were a bit chillier but with clear skies and a midweek full moon displaying to best advantage..

This year saw the best, and more importantly, most consistently good Glastonbury weather since at least 2003, and in many peoples' estimate, 1993 to 1995. All three of those 90s classics (I missed 1993, sadly) were warm, sunny and dry -- 1993 and 1995 were hot).

So you never know, we just might move back into to a 90s-ish pattern of successively good Glastonburies next year.

After reading this thread's updates leading right up to the festival I can fully appeciate the difficulties dueing messy and ever shifting synoptics for forecasters. Pinning down exact detail until very near the time muct be very hard. Like last year (2009) but even more so, down in Somerset we seem to have benefitted from a very late but very welcome upgrade.

In consequence, one of my best ever and this one was my fifteenth. Debbie is more heat averse and had to shelter more, with which I did sympathise honest .... luckily we had crew access to some shady and half empty backstage bars.

But for myself, I loved it all! Best holiday ever ... I hope others had as much fun and games.

[Deepsky]

Do you have the temperatures from glastonbury festival? Be interesting to see just how hot it did get

[William of Walworth]

Do you have the temperatures from glastonbury festival? Be interesting to see just how hot it did get

Sadly not, and I wish I had. Unreliable-ish newspaper forecasts suggested ca 27C or 28C daytime for the Saturday and Sunday, and it certainly FELT as hot as that over those two days. Monday at the end too.

Prior to the Saturday, 23C or 24C or 25C seemed more realistic, Wednesday to Friday. At the start of the week, onsite before the festival opened, I'd hazard 21C.