[Blog] Glastonbury Forecast 6 - 7th June

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Forecast Number 6 - Issued 7th June

Pressure

There is High pressure to the SW of the UK and also towards the NE, however there is a mini trough towards the SW with pressure expected to be slightly below average. This is consistent with the trough expected in the South West approaches for the mid part of next week, so this may account fore the lowish overall pressure to the SW of the UK. This is definitely a concern, however these charts also allow for pressure to rise again towards the end of the month. .although concerning, pressure towards the end of the month may be slightly higher.

Again there is High Pressure to the SW of the UK and also towards the NE, but this time with slightly above average pressure for the UK.

Between the two this indicates, the UK very much between two pattern, which should allow for a mixture of weather for the UK, a typical British summer in other words.

Temps

Both months have temps above average for much of the UK with the exception of the SE corner, temps above average across the UK, between 0 and +1 for the Glastonbury region for both months, with bigger positive anomalies for Northern parts of the UK. However each forecast for June has seen the above average anomaly reduce so now it is only just above 0, for Glastonbury.

Rainfall

The CFS forecast for June has rainfall around or slightly above average in the Glastonbury area [100-110%], a bit of a higher anomaly towards the Midlands again.

The CFS forecast for July has below average rainfall for the Glastonbury areas [90%] and for areas toward the South West , but above average for the Midlands [140%], this is much better than last weeks update, but still worth baring in mind the rainfall projections would tend to concentrate rain in the Midlands, so the 90% may be slightly understated.

Unfortunately the above doesn't really give that much clarity to the situation, or real information, one way or the other.

CFS Daily runs

Pressure / Synoptics

Date........... Runup to Festival ...........................................................Start / During Festival

30/05/2013 Deep Trough over UK for a week before festival.......LP to NE slowly being edged away by HP ridging up from SW.

31/05/2013 Largely settled but pressure lowering ........................Trough over UK at start, settling down again from S later

01/06/2013 HP for all of June, LP edging up on Mon 24................HP ridging in from South West

02/06/2013 LP week before remains at start .................................LP slowly edges away to NE

03/06/2013 Trough to SW UK ...........................................................Slowly weakens over UK

04/06/2013 Low Pressure in run Up ...............................................HP builds slowly from South West

05/06/2013 Trough over UK ..............................................................HP builds slowly from South West

06/06/2013 Trough over UK...............................................................Trough to NE cover most of UK, showery for SW

Rainfall / Temperatures

Date...........Temps............................................................Rainfall

30/05/2013 Yellow to Orange........................................Wet run-up to festival, mostly dry for festival itself

31/05/2013 Orange/Deep Orange................................Rain at start, dry from Friday onwards

01/06/2013 Orange........................................................ Odd shower, perhaps more general on Friday, and maybe Sat

02/06/2013 Green / Yellow / Light Orange................... Rain most days, wet festival, not washout festival, but mud bath possible due to rain before festival

03/06/2013 Yellow/Light Orange.................................. Wet in build up, damp/wet over most of the festival, possible mud bath

04/06/2013 Yellow/Light Orange.................................. Periods of rain pushing east across UK

05/06/2013 Yellow/Light Orange.................................. Rain/ Showers in build up, drier over weekend

06/06/2013 Green / Yellow / Light Orange................... Wetish in build up, wet/damps start, drying Up

Of the 7 forecasts above, none go for an entirely dry festival, 3 go for a very wet festival, and 4 for a damp, mixed festival, Not particularly good news, but that's what the models say.

UK Outlook for Saturday 22 Jun 2013 to Saturday 6 Jul 2013:

Indications currently show that the weather is likely to be rather changeable through the end of June and early part of July, with westerly winds allowing weather systems to push in from the Atlantic, bringing spells of rain at times. Southern areas look likely to become a little less unsettled later in the period. Temperatures are likely to be a little below average for the times of year, especially in western parts, whereas rainfall amounts look to be close to average in most places.

Again not the best news from the latest Met Office thoughts.

Current Outlook

Currently we are in a settled spell of dry (or mostly dry) weather, which has given some decent conditions across the South West.

However it is set to turn much more unsettled from the West / South West next week.

This is the current GFS run, which tries to ridge High Pressure from the south and minimise the unsettled nature of next week.

12 and 15 June

18 and 23 June

If we look at ensembles

The GFS op run is drier and has higher pressure than the majority of the ensembles next week. Pressure drops next week according to the ensembles to an average of 1010mb, this steadily rises close to 1020mb by the end of the run and precipitation rates falls a little.

No question that the GFS offers a glimmer of hope for southern areas as we lead towards the Glastonbury festival.

ECM has suggested a more unsettled outlook. Charts to follow

NOAA Upper charts

6-10 day outlook this has a trough to the SW of the UK

8- 14 day outlook has a trough to the SW of the UK

Both show a very unsettled next couple of days and ahead of Glastonbury we don't really want an unsettled pattern the week before, one as it would leave the ground wet but it may also start a pattern which may be hard to shift.

Overall Summary

A lot of analysis tonight, which has shifted to the more reliable models. Overall not the best of news, hints of a unsettled period of weather in the run up to the festival, and for those wanting a dry festival, we want the trend of a ridging Azores High, otherwise a trend towards an unsettled festival seems likely. I think a mixed festival is the most likely at the moment, and weather like we have seen over the past week the least likely option.

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