Summer Forecast Continued.

[Robbie Garrett]

Explain this to me please? Why does the Metoffice keep chaning it's forecast, first it was supposed to be a mini-heatwave then a washout. Now they are saying some rain but some rather very warmish interludes with fine days. Still unsettled but the chance to see some hot summers days? Could August turn out to be a scorcher then?

[ZONE 51]

Explain this to me please? Why does the Metoffice keep chaning it's forecast, first it was supposed to be a mini-heatwave then a washout. Now they are saying some rain but some rather very warmish interludes with fine days. Still unsettled but the chance to see some hot summers days? Could August turn out to be a scorcher then?

Weather prediction Models are changing with every run that can be up to 4 times a day, the forecasts are updated as the models change-which of course makes sense, data is collected from the atmosphere-for example, and fed into a massive data base, this then creates the model runs which then is used to create a forecast by the forecasters. if the medium range forecasts stay the same for 30days because the models are the same each run then wouldn't that be good and also boring! the ups n downs of the models and putting together the forecast is what makes things a bit more exciting.

Lots of models and different models/data are used for - short range/medium range and long range forecasting.

The heatwaves have and are really trying to sweep in, its a battle of air masses, once the heat moves in then its pushed and pulled back down south again. we once again are in a period where heat is hitting the South and some filtering North, its this battle pattern thats been on and off for a long time, there is a chance that an area of High pressure will move up and sit in the right place and bring widespread blue skies and heat for everyone, the heat in and out of the South throughout August with cool conditions further North as Lows sweep by but thats not to say heat won't arrive up here at times, but hope is not all lost for a Northern summer, its August 1st, and even september can be very warm and more chance of High pressure in that month to!

Edited August 1, 2011 by ElectricSnowStorm

[Robbie Garrett]

Weather prediction Models are changing with every run that can be up to 4 times a day, the forecasts are updated as the models change-which of course makes sense, data is collected from the atmosphere-for example, and fed into a massive data base, this then creates the model runs which then is used to create a forecast by the forecasters. if the medium range forecasts stay the same for 30days because the models are the same each run then wouldn't that be good and also boring! the ups n downs of the models and putting together the forecast is what makes things a bit more exciting.

Lots of models and different models/data are used for - short range/medium range and long range forecasting.

The heatwaves have and are really trying to sweep in, its a battle of air masses, once the heat moves in then its pushed and pulled back down south again. we once again are in a period where heat is hitting the South and some filtering North, its this battle pattern thats been on and off for a long time, there is a chance that an area of High pressure will move up and sit in the right place and bring widespread blue skies and heat for everyone, the heat in and out of the South throughout August with cool conditions further North as Lows sweep by but thats not to say heat won't arrive up here at times, but hope is not all lost for a Northern summer, its August 1st, and even september can be very warm and more chance of High pressure in that month to!

That's a bit more indepth, and sometimes these models never get it right. I've been a victim of poor forecasting - I was sitting in the aircraft at Biggin Hill, forecast (TAF) and current METAR was 'CAVOK' - and this happened https://fbcdn-sphotos-a.akamaihd.net/hphotos-ak-snc3/18771_295037488340_735173340_3482434_7168205_n.jpg

Let's hope August is a decent scorcher, I spoke to the Metoffice this time last year and they where uncertain weather or not we could break 2003s MAX temp record, it could have happened but the high and lows didn't end up where we needed them, otherwise it would have happened. http://www.metoffice.gov.uk/education/teens/casestudy_heatwave.html#p04

I am hoping this can happen. Doubt it though.

[mushymanrob]

I think we can safely say summer 2011 so far has had no shades of 1976 about it. The outlook for the first part of August looks unsettled though warm/very warm. Time is fast running out for a lengthy protracted dry hot sunny period as we saw in 1976, yes we may still see a good spell of very warm sunny dry weather- but the odds are shortening.

its not going to happen is it.... in fact the pessimists back in late june will be proven right dispite a chorus of 'you cant write summer off yet', the point is that until a pattern change occurs, you can!

i dont think that we will get a decent hot spell now, that is 5 days + of 25c+ in the cet zone. tbh id be surprised if theres 3 days...

[BLAST FROM THE PAST]

To write summer off is unwise as short periods of very warm conditions will materialise again as they have done. However, a prolonged pattern of hot sunny conditions have not and are unlikely to develop, well by the time they do if they do too little too late?. There seems to be an overrider here that has kept jetstream [yet again] on more southerly track with a tendency for -ve NAO conditions to develop. ECM for example keen to project this.

It will be interesting to hear what GP summarises as to what has overridden the analogue signal for a shade of 76 summer. It seems that certain teleconnections pointed towards this but some other influence has dominated [i have my opinion as to why ie solar/lunar driven pattern bringing longterm shift south of jetstream, perturbation cycle entered into -ve PDO/La Nina domination which is well correlated with a -ve NAO state dominating may have contributed somewhat] also maybe SST pattern has not followed suit. Similar to last winter which went wrong in latter half as the La Nina eventually took firm hold and seemed to scupper any return to a deep freeze and drove the pattern. This summer pattern has been overridden and teleconnections have not dominated as anticipated.....it happens.

BFTP

Edited August 3, 2011 by BLAST FROM THE PAST

[Robbie Garrett]

It's a shame that this is effectively our Summer, which has been very hot at times. Then again, most people wont moan if the mercury hits high 20s instead of high 30s for weeks on end will they?

I am wondering can we still break this years hottest temperature in September? Our seasons seem a bit extreme of late, maybe 30+ in September, if weather conditions permit?

[TonyH]

its not going to happen is it.... in fact the pessimists back in late june will be proven right dispite a chorus of 'you cant write summer off yet', the point is that until a pattern change occurs, you can!

i dont think that we will get a decent hot spell now, that is 5 days + of 25c+ in the cet zone. tbh id be surprised if theres 3 days...

A large portion of the CET zone has probably now had 4 successive days over 25c, and with a chance of 5, so quite a decent spell of Summer heat.

Coventry has reached 25c these past 4 days (including 28c on Monday), as I should think has most of the East Midlands.

Edited August 3, 2011 by Tonyh

[Weather-history]

Do you think anyone would notice if we slipped in a quick title edit now?

You could have one of those one arm bandits where you press the lever, the dials spin around and instead of bells, cherries etc, we have the numbers that make up a year of the past

[Weather-history]

A sobering thought, the last +ve NAO summer month was July 2006, we have had 14 consecutive -ve NAO summer months.

Make that 15, July came in negative.

And the way the charts are looking, August looks like heading the same way.

Edited August 3, 2011 by Mr_Data

[Bluebreezer54]

Make that 15, July came in negative.

And the way the charts are looking, August looks like heading the same way.

Mr Data. Your head for stats is truly impressive. I am trying to get to grips with the NAO and what it means to our weather. For the likes of me can you please simplify what the difference is between a +ve NAO and a -ve NAO ? I have tried to research this, but would appreciate the advice of some experts on the subject, rather than search all over the internet.

Edited August 3, 2011 by Bluebreezer54

[Weather-history]

Mr Data. Your head for stats is truly impressive. I am trying to get to grips with the NAO and what it means to our weather. For the likes of me can you please simplify what the difference is between a +ve NAO and a -ve NAO ? I have tried to research this, but would appreciate the advice of some experts on the subject, rather than search all over the internet.

http://en.wikipedia.org/wiki/North_Atlantic_oscillation

[BLAST FROM THE PAST]

Make that 15, July came in negative.

And the way the charts are looking, August looks like heading the same way.

Jetstream stays south of norm, storm track much further south, this is likely to continue and is becoming the 'norm' state. I remember only 4-5 years ago how this type of pattern was believed to be consigned to history by many on here, now it just won't go away.

BFTP

[Ladyofthestorm]

Talking of which are my eyes decieving me, but is the NAO forecast to become less negative and move towards positive, in the next few weeks. We seem to be right in the NAO doldrums right now.

Edited August 5, 2011 by Ladyofthestorm

[mushymanrob]

A large portion of the CET zone has probably now had 4 successive days over 25c, and with a chance of 5, so quite a decent spell of Summer heat.

Coventry has reached 25c these past 4 days (including 28c on Monday), as I should think has most of the East Midlands.

i live in the cet zone, i can assure you that we and a large part of the uk have not had 4 consecutive days of 25c+ .... why would i lie? some areas in the uk is not what i was alluding too. recent hot spells have not matched july 06, id be surprised if you could find anyone who would disagree.

A large portion of the CET zone has probably now had 4 successive days over 25c, and with a chance of 5, so quite a decent spell of Summer heat.

Coventry has reached 25c these past 4 days (including 28c on Monday), as I should think has most of the East Midlands.

i live in the cet zone, i can assure you that we and a large part of the uk have not had 4 consecutive days of 25c+ .... why would i lie? some areas in the uk is not what i was alluding too. recent hot spells have not matched july 06, id be surprised if you could find anyone who would disagree.

[Methuselah]

Is that because the jetstream has been waving south, in this part of the world, or because it's running south all over the NH?

[BLAST FROM THE PAST]

signs of a decent second half of Aug? Will the NAO state go through a period of -ve? Chances are there.

Re the jetstream, it certainly has been shifted on more southerly track here. Is that because of more amplification? Interesting point

BFTP

[The PIT]

Further south than normal but further north than the last two years hence the reduction of rain. I hope I'm right on that.

[TonyH]

i live in the cet zone, i can assure you that we and a large part of the uk have not had 4 consecutive days of 25c+ .... why would i lie? some areas in the uk is not what i was alluding too. recent hot spells have not matched july 06, id be surprised if you could find anyone who would disagree.

i live in the cet zone, i can assure you that we and a large part of the uk have not had 4 consecutive days of 25c+ .... why would i lie? some areas in the uk is not what i was alluding too. recent hot spells have not matched july 06, id be surprised if you could find anyone who would disagree.

I got your point first time around

Don't think I accused you of lying...

I believed you were trying to say that the CET zone was not going to record above 3 days over 25c, however much of the CET zone did!

East Midlands airport is another example:

Edited August 5, 2011 by Tonyh

[mushymanrob]

I got your point first time around

Don't think I accused you of lying...

I believed you were trying to say that the CET zone was not going to record above 3 days over 25c, however much of the CET zone did!

East Midlands airport is another example:

after this spell... and i do qualify a 'lengthy hot spell' as 5+ days over 25c+ . that i believe, will not happen. i said that im not expecting even 3 days of 25c+ ... that remains the case.

[mushymanrob]

East Midlands airport is another example:

how odd.... ema is c7 miles as the crow flies and recorded 27c on monday when my local long term amateur station only got 23c on monday... and ema is higher elevation... maybe the sun shone on ema for a spell... it didnt here for more then a breif glimpse.

[mushymanrob]

well who will place a bet on summer not being over? looking at this mornings runs would suggest that there will be no pattern change by the end of august, and in the cooler times its starting to feel autumnal in the quickly shortening days, the best of the summer blooms are over, the swifts have all but gone, theres that autumnal tint to the morning air, and with 3 weeks of summer to go... lets face it, the 'doom mongers' will be proven right (unfortunately).

ok, back in april i thought pattern change would happen sooner rather then later resulting in another washout summer. i was wrong. the pattern has lasted from early may, and here at least has been very dry. we missed the heaviest of the rains, streams are very low and the grass is pretty brown. so whilst i thought the pattern would change resulting in a wet summer, was wrong, i still expect that when the pattern changes it will result in a lengthy wet spell. that often seems to follow a long dry spell.

[ohno]

^{Summer is well and truely over. Once we get into this kind of pattern it goes on for months at a time. Sure we have had good days inbetween but thats just been a let up between the low's..}

[Airedalejoe]

I'd have to echo the words of Paul Hudson, never has a LRF gone so spectacularly wrong so quickly!! A bummer considering GP's past record.

I don't know how many mm's have fallen or how many hrs of sun or av. max's min's etc but suffice to say in my neck of the woods summer's been rubbish, cloudy/cool with no end in sight.

[Evening thunder]

I would place a bet on summer not being over, because as mushymanrob said in his post, there's 3 weeks of summer to go. Even if the weather isn't necessarily summery..

I'd place a bet on summer being over for me on the 1st September, though for some people this may be around the 22nd September.

[Ladyofthestorm]

Summer is over me thinks, we have had a decent June July and first part of August, which we cannot complain about. Im going to write off the next two weeks of August for the North, the south maybe a bit luckier, but that is by no means certain. September is usually a good month in terms of temps and sunshine for us up in the north, BUT so is usually May, so therefore Im writing of september as well.

Mild wet winter anyone?