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Latest angular momentum budgets nicely underpin the shorter term modelling as last discussed on Sunday - but with further added interest. There is enhanced phase tropical forcing across the Western Pacific (MJO related) predicted in current models which adds westerly momentum to the planetary weather/climate system and if verified would further increase upward tendency in relative atmospheric angular momentum (to the base state) The strength of MJO waves impact on global weather patterns by interfering with the dominant ENSO base state and any eastward moving high amplitude tropical forcing will act 'destructively' on the on going cooling SST profiles across the Pacific . Positive frictional torques are still sustained and continue to lead the way for mountain torques This also supports the overall continuing trend of calculated momentum tendency (torque plus tropical forcing budgets) heading upwards - more especially any +ve mountain torque event which adds more atmospheric westerly momentum to the extra-tropical budget than +ve frictional torque. Feedback lags from mountain torque events are up to 10 days - which underpins future amplification and height rises in modelling These changing tropical and extra tropical elements need to be assessed against a total angular momentum budget that has been running through much of July and into August at between -1 and -1.5 SD - reflecting a modest low level global atmospheric angular momentum state (GLAAM) Putting all this together, the signature expression of the Global Synoptic Dynamical model (the Global Wind Oscillation) reflects the increasing momentum by heading from low AAM phases 1,2 and 3 back into Phase 4 once more . Taking into account the +ve global torques and indicated increased tropical forcing both adding further westerly additions to the atmosphere, there are good grounds to see a rise in total angular momentum. GFS model suggests that the GWO has already moved into weak Phase 5 (high momentum state) before indicated orbit back to low Phase 8/0/1 signal. Usual disclaimer - don't take forecasts at face value. These are especially subject to changes day to day. But could any higher AAM signal hold long enough to force a meaningful pattern change from the summer default? It is a Nino like GWO Phase 5/6/7 orbit signal that holds the key to any holding high pressure synoptic in the further outlook period. The summer so far has been prohibitive of UK/European upper ridge synoptics because of the atmospheric circulation being pre-disposed to a low angular momentum Nina type. This point has been stressed repeatedly in each post as a means to try and help manage expectations. So I would still be cautious of drawing conclusions from face value intra day modelling. They will be highly sensitive to the balance of GSDM (GWO) modelling. Sustained upward tendency of AAM is required to push the total atmospheric circulation into a less Nina like signature. Until that happens, any modelling which tries to extend the Azores High north across the UK and Europe continues subject to some backward adjustment. However, providing we see the predicted higher amplitude tropical forcing in the Western Pacific, then there is a reasonable chance of an anti-cyclonic spell - at least for a time and more especially further south and east. No IMBY considerations at all here - simply a refection of how I think things stand. Assuming tropical activity forecasts verify, an eye also needs to be kept on a sudden and immediate retreat from MJO Phase 6/7 as this will indicate that the SST processes in the Pacific which reflect potential Nina conditions establishing through the autumn are gaining ascendency through too much easterly wind additions to the atmosphere - despite the current indicated attempts of the atmosphere to add westerly inertia to it (and create eastward and northward propagated ridges). Such a retreat and death of active tropical forcing will result in a fast reversal in any AAM spike - and accordingly any fine weather synoptics will revert to retrogression of the pattern back to a more withdrawn Atlantic Ridge and return of the Iceland/Scandinavian trough. So for the balance of reasons and evidence given, I'm rather inclined for the time-being towards a half way house and wait to see how signals evolve further. But for now at least, the medium term is looking a bit more promising than it has done recently

Umbrellas could feel rather lonely over the next two weeks if the 00z ECM is right

Yes the overnight ens are still trending towards a nice spell towards mid-month. We can see on the gefs charts how gradually the jet starts to track further north compared to the near term. Compare days 4/8/10 as last night's gefs showed,the Azores high extending ne and with time stretching across the UK towards Scandinvia. The ECM mean is a promising chart too at day 10 hopefully this upbeat trend continues but the signs are there that the Icelandic trough shrinks north as the Azores high noses in quite strongly going in to the second week of the outputs.

A UK centred high from the middle of next week then settled. ..Please make it so!

Morning all Plenty to cheer fans of settled conditions, especially in the south, on the morning OP output. All the models are showing, after a brief hiatus early next week, an extended spell of anticyclonic conditions as the Azores HP moves in close to or over southern Britain. I'd go for warm or very warm rather than hot based on what I'm seeing as the main airflow still comes off the Atlantic. GFS further into FI hints at the core of HP shifting north or north-east and that could import some hot air from the near continent but that's a very long way off and far from certain. It's also possible the HP regime will slowly relax back into the Atlantic as a more traditional North-South split takes over and retrogression isn't a completely lost cause either. All that being said, it looks increasingly settled from the middle of next week onward, especially in the south but improving north and west with time. Warm or very warm by day but pleasant.

Summary of charts this morning: A decent weekend away from the north, cooler air with a weak front and showers progressing south Sunday/Monday, then a cooler airstream Tuesday till Thursday but mostly dry with just a few showers or minor troughs, most significantly on NW coasts I suspect. Then Thursday/Friday onwards for the rest of the runs, High Pressure is dominant over the UK, lots of calm, settled, sunny weather; temperatures recover to warm or possibly very warm, the only significant unsettled weather being for the far NW but they will join in with fine weather often. Good agreement between GFS/ECM/UKMO on these details.

If you look at the 500mb pattern now and at 240h on the Extra link, you can see how it is predicted to change. https://www.netweather.tv/secure/cgi-bin/premium.pl?action=gfs;sess=60060447a8a2d3a3d5d864616c095105 It is looking like this may be the pattern that devekops in the 6-10 day time scale as the synoptic idea fits the 500mb anomaly charts. So maybe we are about to have one of the short term ridging set ups that I think Tamara commented on? http://www.cpc.noaa.gov/products/predictions/610day/500mb.php http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html The upper ridge and higher +ve 500mb heights being predicted seem to suggest the upper high and thus probably the surface high will be pretty much over the UK? Even the 8-14 NOAA chart still has some indication of +ve heights in the UK area although no actual 500mb contour ridge over the UK This is quite a change from the Atlantic ridge-Scandinavian trough upper pattern predicted up to 2 days or so ago.

These GFS +210 charts will warm the cockles of many Netweather users hearts. For the first time in a long time, the jet stream seems to be heading north where it traditionally belongs in summer... ..leading to a big high centred over the UK.

A Uk centred high would be a real joy..let's hope it comes to fruition we've waited since the beginning of June for this!

Very good 6z Op run with high pressure in control from the middle of next week until the end of the run, the only rain of any signifance away off in the Outer Hebridies as the jet is forced North East. Could be a very very good end to the Summer across most of the country.

A very happy GEFS 00Z ensemble set too. 17 out of 21 members have no trough influence for the UK at all between D7 and D10. The other 4 can hardly be called unsettled either - the south stays pretty good on all 21 members. (I haven't posted the link as the whole set will change in an hour's time!)

The GEFS 12z mean shows an increasingly fantastic spell of summery weather once we get through the cooler blip early to mid next week. The Azores high becomes our Best friend, a friend who wants to stay through mid august and even longer! This would be most welcome in a misfiring summer so far with a nationwide increasingly warm & anticyclonic extended outlook..from what I've seen today, the future is looking very bright for the uk with hopefully the best of this summer still to come!

It's a bit like the models have Rollerblades on right now? The ECM in particular has gone absolutely round the houses on the outcome for the end of next week, from Arctic northerly to continental southerly - absolutely massive pattern changes in just a few days. GFS has been much much more consistent - just hope it isn't consistently wrong! I think we need to wait a couple more days to see what kind of HP build we get into the UK. I can't quite believe the GEM and ECM can demolish a North Atlantic block so destructively that it doesn't even topple into a UK high, at least temporarily.

Yes Karl according to the GEFs apart from a few showers the next couple of weeks; although starting rather cool,look quite decent as we head towards mid-month. Something of a change in the pattern is on the way with a transient northerly toppling into a +ve height anomalies across N.Europe/UK in week 2. Day 5 and 10 charts if that verifies we could see a nationwide Summery spell,a rare thing this Summer.

Only the Best mean charts of the summer, hope this summer has saved the best until last...I'm starting to think it has!

Dec 2010. Quite simply a month that will never be beaten. We didn't get much snow in Cannock in relation to other places, but the depth of the cold was remarkable. Not getting above -6c on Christmas and Boxing Day with a few inches of snow on the ground. I don't think any of us will see cold like it again in this country with a warming climate.

Yes, just thinking the same myself. A great Saturday to look forward to

I completely glossed over the fact that this weekend looks very nice across most of England and Wales with a good deal of strong August sunshine and temps between 23/25c tomorrow, feeling very warm tomorrow due to light winds. Sunday looks much windier but temps still around 24c so no complaints further south..most of tomorrow looks pleasant further north before an unusually deep depression sweeps wet and windy weather across Scotland with westerly gales on sunday with sunshine and blustery showers across the w / n of scotland including the isles.

On the plus side we have a terrific Gefs 12z mean longer term, you couldn't ask for better mean charts than those in a British late summer but the Gem 12z is a let down and to a lesser extent, the Ecm 12z which looks decent for the south beyond the cooler changeable blip next week but absolutely pants further north and isn't it about time we had a nationwide warm anticyclonic spell?..yes of course it is!

Is it not more the case that a spot which would have been counted as one back then is now looked at in fine detail and is actually a cluster which is counted as a number of little specks rather than one bigger spot.

Morning gang, apart from Tuesday this week's weather had not been bad at all here! The "cold" snap for next week look like a fart in a thunderstorm before warmer conditions build in. And still.. Some people with a brain the size of a pea want the cold conditions in august and even colder. Not realising clearly the implications to crops up and down the country which of course has a serious financial cost to both the farmer and consumer! All because they want some poxy cold weather, be patient till it's the season for it!!

The Ecm 12z shows next weeks cooler incursion becoming shorter and weaker, it's being shunted further east, it does become cooler for a while next week but not that cool. Pressure soon starts to rise from the southwest during the second half of next week and its really all about the Azores high (ridge) building in and then rebuilding in with increasingly fine and warm weather, the run ends very encouragingly.

The Gfs 6z op run shows a fine warm weekend coming up across most of England and Wales, unsettled and cooler further n / nw and then a glancing blow northerly next week from monday with temps briefly dipping below average and some rain and showers but with sunny spells too but some unseasonably cold nights with slight frosts in rural northern areas before the cool supply is cut off by a ridge of high pressure building NE into the uk..and from there, it just gets better and better during low res which shows the summer we have been missing this year, scandi height rises, link up with the Azores high bringing sustained beautiful warm / very warm and anticyclonic nationwide bliss!

or roll on winter

Your making me jealous! "Autumn" in Blighty is now fast becoming 1 long hot Indian Summer interspersed with mild Atlantic mush and the odd toppler or/and Inversion Cold snap, with true autumn patterns (storms!) now only arriving in "winter" and "spring" with scarcely even any Inversion Cold or topplers! I wouldn't read too much into the August decline post 2004. We always seem to get these quirky exceptions to the greater changes effecting other months. Remember the cool 1960s? This decade actually was the warmest decade for both June and October at least until the 2000s. June and October then cooled into the 1970s and didn't start warming dramatically again until the 2000s. The cool but very changeable 1970s was also the warmest decade on record for December. The very cold December 1981 also masked an otherwise very mild decade for December in the 1980s which was again another cool but very changeable decade for the other months. December also erratically cooled from 1990 through 2010 which of course was an otherwise very warm period for the rest of the year. On the other hand the very mild 2010s seem to be masking the exceptional cold of December 2010 and March 2013 so far. 1 thing that can really shake things up in August is the paths of former Atlantic Hurricanes. The often reviled August 2014 had good potential to be very warm as with the rest of 2014 however an abrupt and rapid shift in the path of Ex-hurricane Bertha from Iceland southeast into France caused a complete but temporary flip in the otherwise stubborn Mid-Atlantic Trough/Eurotrash Ridge pattern with northerlies and cold zonality westerlies giving us our coldest August since 1993 only for the Mid-Atlantic Trough/Eurotrash Ridge pattern to return once August was over. In a similar vain the southerly tracking Ex-hurricane Charley in the August Bank Holiday of 1986 played a key role in maintaining the very cold North Atlantic Blocking and southerly tracking Jetstream pattern which had dominated most of 1986 thus giving us a very cold August and very cold September to round off the cold for that year. On the other hand August 2004 was very wet but also very warm due ex-hurricanes taking a more sluggish northern track through Britain.

In 2012 there was a large area of broken and fragile ice sticking out from the central pack toward the Bering Strait around this time. Then there was a big storm, called GAC 2012, Great Arctic Cyclone of August 2012, which wiped most of that ice away over the course of a few days. We had a drop of over 1,000,000km2 in 7 days, the largest 7 day drop in August on record, by a long way. Now we're already behind 2012 and it's just about to lose over 1,000,000km2 of extent over the next week so it's hard to see how we can keep up, let alone lose more than it. The upcoming weather doesn't look great, but I don't think it's enough to challenge 2012.

Tonight's GEFS 12z mean shows a short-lived cooler incursion from the nw / n next week but it's quickly shunted away to the NE by a ridge of high pressure building in from the southwest during the second half of next week and really from then on its good news as the Azores high becomes increasingly influential with largely settled and warm / very warm weather with temps into the mid to upper 20's celsius across the southern half of the uk.., looks warm and settled in the north too with low 20's c. As mean charts go, these look very encouraging through mid to late August.

All over the place though, isn't it? For next week, the ECM alone has progressed from heatwave, to arctic blast, to mid-Atlantic toppler, to UK High and back to a high pretty similar to what we're going to get this weekend! I'm wondering now if the Atlantic is actually going to flatten the pattern further and we'll end up back to square one within 10 days with an encroaching trough to the NW. Let's hope not - let's hope the models have final settled on the right outcome as it would be very welcome further north I suspect.

Fingers crossed Phil, encouraging signs for the rest of this summer today.

I actually lived through those times and my remarks are based on my impressions at the time. During a previous part of my misbegotten life I was involved in research and actually collected raw data. I saw at first hand how stats can be manipulated to suit the requirements of a sponsor. My recollections of the 1950s and '60s are extremely keen - there's a reason for that. That's why sunshine stats are meaningless - most of this sad excuse for a summer has been overcast with any sunshine recorded occurring in the small hours when the majority are asleep.

Manchester Summer Index for the summers of the 1960s. 1960 217 1961 203 1962 197 1963 194 1964 197 1965 189 1966 192 1967 223 1968 215 1969 234 Those figures are not as bad as suggested, infact 1969 is a very respectful figure. Compare 2008 with 168 and 2012 with 164. I point out that summer covers June to August. How many memories of summers at school are distorted by just remembering the school holidays? For instance a superb August may give an impression of a wonderful summer overall when infact June and July were mediocre. Also vice versa, with a poor August. The Junes of the 1960s were not on the cool side overall. June 1962 was a dry month for England and Wales, it's the 5th driest June on record.

Another superb Gfs 12z in low res, again thanks to scandi height rises and a really blocked pattern with no Atlantic filth possible, I hope the gfs is on to something here. High res shows a fine warm few days ahead further south but sunday brings strengthening westerly winds associated with a depression which pushes wet and windy weather across northern Britain late saturday and overnight. Next week shows an increasingly watered down Northerly incursion but even so, temps drop below average with some rain and showers around and chilly nights with mid to upper single digits celsius but high pressure cuts off the cool air with a warm and fine end to the next working week, a bit of a less warm / less settled blip at the end of next week before things become as peachy as the earlier 6z..it's what we have been missing through this patchy summer so far.

Not especially weather related but certainly seasonal:

Guys....For God's sake will y'all stop moaning! I recall the school holidays back in the Swinging Sixties: sunshine on the day we broke-up, sunshine on the day we went back - and endless days' cack in between. What has changed?

Gavin, can I make a request that we don't give Exacta Weather publicity? Up to you whether you agree or not but I don't think they should be included in discussions, they are not legitimate forecasters and IMO are fraudsters. Madden is an attention-seeking charlatan.

The GEFS 6z mean shows a glancing cooler NWly flow for a time next week but it's soon shunted away by high pressure building in from the southwest from later next week onwards and further ahead the Azores high is increasingly influential across the UK with largely settled and warm weather across at least the southern half of the uk..August would turn into a good month further south if anything like this occurs.

GFS 06Z continues to blow away the northerly at an increasing speed - just 2 or 3 cooler days midweek now before this. It may end up a really good week if you like sun but don't like it too hot, no deluge of rain around that I can see.

This weekend looks lovely the further south you are according to the Ecm 00z with increasing warmth and humidity, in any sunshine temps should respond with mid to upper 20's c on sunday and monday in the s / se. For southern & southeast England it's a cracker!

Thats a decent ECM this morning! Very brief northerly before the azores high ridges back in, OK nothing overly hot or warm but after a lovely 2 or 3 days and a cooler few days its back to high pressure in control-

The ukmo 00z shows high pressure still influencing the south by next midweek, not bad at all further south, it does become cooler and fresher but nothing dramatic. The very cool plunge hardly even reaches the far north!

No sun today in happy hounslow?

Here it has delivered 2 cool, wet and overcast days, and 1 average day.

At Keswick, my local Met Office station, the August average to 2005 was 19.9c since 2005 the highest mean maximum has been 19.8c, so in effect every August since has been below average. This has actually knocked the 30 year average maximum temperature down 0.5c to 19.4c just because of the Augusts 2006-2015.

16c 16c 17c 17c 16c 15c 14c 14c 14c is the forecast maximum temperatures here for the next 9 days whats the point in waiting for the inevitable?

What has happened to August? Nothing, it is still in the calendar. I made a post before in the summer 2016 thread on other periods where August was a poor month.

August is 3 days old. Come back in a couple of weeks and ask the Q.

I was on the One Show last night talking about long-lying snow on the Cairngorms. You can find it here (if you're interested): http://bbc.in/2aOzBjV

I'm not sure if this is a weather question, but it's something that's been on my mind for a long time. When ice ages occur do they happen in both hemispheres?

Ice Ages tend to occur when the tilt of the Earth reduces a couple of degrees which leads to summers being markedly cooler as the total insolation near the summer solstice (for each respective hemisphere) then drops by 10% or more, other things being equal. This leads to a situation whereby snow that has fallen in the winter persists over a wide area (because of less incoming insolation) and this snow-cover continues to reflect much of the Sun's heat so that large areas of the sub-arctic and Antarctic remain much cooler. Snowfall the next winter falls on already snow-covered ground and new ice-sheets can build up over land at astonishing speed with the ice-sheets reflecting most of the slightly weaker summer sunshine. Over the years as the ice-sheets thicken the top of it is exposed to cooler air higher in the atmosphere and this eliminates summer melting further so the ice sheets thicken even more. As the sea-level drops a little (due to so much water locked up in the ice) and cold airmasses flow off the ice into mid-latitudes winter and summer, this cold and the effective higher elevation of mid-latitude land areas means more snowfall in these areas in winter which could persist through the summer. Hence the ice sheet spreads into lower latitudes and even more of the Sun's heat is reflected back into space encouraging further global cooling. This leads rapidly to much more ice and the Earth plunges into a severe Ice Age. One of the Milankovitch Cycles works to bring about opposite changes in solar input in each hemisphere: The Earth's orbit around the Sun is not totally circular but forms a bit of an ellipse. It means the Earth is closer to the Sun at a certain time of the year but further away six months later. In the past the ellipticity of the Earth's orbit has been such to cause the Solar Constant to vary by up to 25% over a year. Ice Ages happen when the Earth is at the farthest point in the Northern Summer which makes summer sunshine over the entire Northern hemisphere wide area 10% or more weaker and this allows snow that falls in winter (over the Arctic and mountainous areas of North America, Europe and Asia) to persist throughout the summer reflecting the Sun's heat and encouraging cooling and the spread of ice. In winter in the Northern Hemisphere the Earth would be closer to the Sun in this situation but with the Northern Hemisphere tilted away from the Sun in winter the Sun is low in the sky and so the warming effect of being closer to the Sun is mitigated by the fact that the Sun is low and so a 10% increase wont add a lot of heat. In any case a little more warmth in winter in higher latitudes means more moisture in the air which leads to heavier snowfalls where the air is still cold; thus this development encourages the rapid onset of new ice-sheets in high northern latitudes. But in summer, when the Sun is high in the sky and up for many hours each day a 10% drop in the Solar Constant has a massive impact and so the net effect of an elliptical orbit with the Northern Summer at the furthest point is a strong net cooling of high and mid-northern latitudes. The Southern Hemisphere in this situation would have its summer with the Earth closest the Sun and in this situation the Antarctic ice-sheet would start to melt with the Sun being stronger. That said, the Northern Hemisphere with its greater land area and mountain ranges would have snow accumulating on them over a much wider area than the melting going on at the edge of Antarctica- so the net effect of the Northern Hemisphere summer occurring when the Earth is furthest from the Sun in an elliptical orbit is likely to be a sharp global cooling leading to an Ice Age. Usually though, it is the changing tilt of the Earth that tends to trigger Ice Ages- by weakening the spring and summer sunshine in mid and high latitudes in both hemispheres. Decreasing the tilt of the Earth also means a little more sunshine in winter, so it would (initially) make winters less cold and, it must be said, more able to carry moisture leading to heavier snowfall in areas where the high-latitude land areas still get cold enough: More snow in winter and less melting in summer means rapidly-increasing ice-sheets that reflect away the Suns heat bringing about an Ice Age in the space of as little as 100 years. This happens simultaneously in both hemispheres as Earth's tilt decreases.

I just wait and see whats forecast, or if it happens I drive out and try and chase, don't use anything technical, just eyes and ears