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ECM overdoing the low - Definite On the other hand the ECM suggesting a way to pull up a pure source of hot continental air. This chart interests me as it's a evolution which will deepen and sharpen the trough and allow a proper plume event. The UKMO is also sending a low towards Iberia along the subtropical jet, again this could lead to a possible rise in temperatures. The GEM is much slower and the GFS phases the low around day 5 and has no effect later on. Given the longwave pattern, the chances of developing warmer weather is pretty high, this summer has proved that quite well as trough dominated FI charts have often been shifted westward with time. Something to watch as always. This coming week is looking pretty reasonable, never dropping to even average levels of temperature in the south and even the north seeing better conditions for a time. Like this week I suspect that any rainfall will be showery in nature as fronts struggle to make an impact against the Sceuro block. So the convective thread should be kept ticking over this week.

Although it is a messy picture today there are areas that interest me. Firstly I notice the CAPE levels indicated by GFS for this afternoon with around 700-1000j/kg being progged, this almost mirrored by the NMM although CAPE just slightly watered down on here for the same sort of time. Lapse rates are up earlier in the afternoon with the highest lapse rates transferring northward through the afternoon and evening period. ELT's also looking favorable, these two things together would indicate a possibility of hail and frequent lightning as storms mature. Although there is some deep layer shear it is probably not enough in itself to allow storm organisation but low level shear and speed shear is looking better. This creates some interest in the early to mid afternoon for the Midlands into Northern England as there appears to be a slight tornado risk should any storms organise. Shear does look to increase from the south later in the afternoon and evening but this may be too late for the highest storm risk area as it moves northward (although keep this in mind for later). Clearly convective precipitation is not in short supply with the picture looking messy. This may actually prove to work against storm potential as we may just end up with a mass of heavy rain pushing north. Another thing that has caught my eye is the NMM developing a small area of enhanced CAPE (upwards of 1000j/kg) around Gloucestershire mid-late afternoon and a subsequent thunderstorm developing and moving NE through the Midlands into the late afternoon and evening. It is a small risk but if this did happen then this will form in the aforementioned area of more favorable shear and could develop into a more organised storm cell for a time. At this same time, looking at the wind charts, you can clearly see convergence over N England, this having pushed northward through the middle of the day and another area from the Gloucestershire to Midlands area. Overall it is a very messy picture and a complicated forecast. I am probably out my depth here but putting things together this could become a day of plenty of cloud and plenty of rain with the odd rumble. Alternatively today could become another good day for storms. If storms do occur there looks to be two prime risks. The first is along a band that pushes north across the Midlands by midday and into Northern/Eastern England this afternoon. The second is a lesser but more interesting risk of more a more isolated storm pushing NE from somewhere just inland of the Bristol channel up through the Midlands. Charts provided by netweather and www.lightningwizard.com/maps

Rain certainly has arrived now,but got a couple of shots of the gust front before it started.

I'm merely stating that the general level of thicknesses, uppers and sst's at the moment over the uk area leads to higher than average surface temps. That means when we have surface features that we might expect to lead to a cool day, we see temps managing to get to average at the very least, given a limited amount of solar input. Similarly, less than inspiring charts will lead to quite high temps in reality. perhaps think of the whole summer temp pattern being shifted a few hundred miles north of where we would expect it to be. at the moment, I'd say that londons 2014 summer climate is more akin to what I would expect to see just south of Paris.

Can you support this because people might read it and think it's true? And for some reason you have omitted climate change. This is a bit jumbled but still arrant nonsense. Pumping billions of tons of carbon into the atmosphere that was stored as part of a natural cycle patently must alter the carbon and hydrological cycles. Plus of course altering the natural radiation balance. Totally irrelevant and for some reason keeps getting repeated. Lung cancer occurred prior to tobacco. Ergo there is no link.

No repeat of the yesterday's GFS 12z plume this evening, it had little support and even the hi-res are toning the uppers down for mid-week. From Monday the models continue to show a slack pressure flow over most of the UK with the Scandi ridge to the east and the trough centred around Iceland: Around late Wednesday the trough edges E/SE: Its a slow process but it does enough to put the majority of the UK under the influence of the jet; D6: A short wave and some fronts look likely to bring unsettled conditions to most. By D8 the GFS op has us under a shallow trough with the Azores a bit player for a couple of days but by D10 we are heading for another trough for 3-4 days: The control very similar to the op and maybe we are seeing the way forward. GEM is not dissimilar, it just notches up the cooler, wetter and windier scenario: UKMO strongly resembles GFS at D6: This all ties in with this morning's ECM run up to D9 where it goes off on one (cut off low) with little support from the ens: Despite the outlook I suspect temps in the SE to still be 2-3c above average on the dry days, and never too far away from warmer continental air, but closer to average in the north. Wetter the further W/NW and with high SST's there could be high precipitation totals as the cooler air moves in later next week.

Here's more pictures:

What to say, really. Not much has changed looking at the ensembles. Out to day 10, heights continue to build to our NE, with the core centred east of Finland; thus, the UK struggles to get in on the party in any great way, esp for western parts. Where the trough continues to dominate/control, up to and beyond day 10. days 4-9, 8-13 Height anom. temp anom days 7-12 GEFS height anom days 0-16 6Z GFS Ens - Belfast, NI Looking at the ensembles for Belfast where I am currently on holiday - the NW looks like staying unsettled throughout, with rain spikes aplenty and pressure struggling to rise above 1015hpa; the 6z op was a clear outlier post day 8 in terms of rising pressure, So, GEFS and ECM ens continue to show a changeable and at times unsettled outlook for the next week and beyond, most unsettled in the west, with the SE seeing the best of any brighter periods. Just to mention, this is a forecast from the models, not a hope cast. I do realise this may not accommodate most in here. But it is what it is. A forecast.

Storm & Convective Forecast Issued 2014-08-02 10:12:31 Valid: 02/08/2014 1000z to 03/08/2014 0600z THERE IS A RISK OF THUNDERSTORMS FORECAST Synopsis Slow-moving upper trough axis lying N-S across western side of the UK and down into Iberia continues to drive a cyclonic S to SWly flow across much of the UK, veering W to NWly across EIRE. At the surface, an area of low pressure over the Irish Sea will slowly drift N, to be centred over SW Scotland by 00z, associated warm lying SW from SE Scotland to Liverpool Bay will move N while cold front lying S to Dorset will moves ENE, the cold front clearing the E coast by 00z. ... ENGLAND, WALES and S SCOTLAND ... Moist airmass will cover much of England and Wales today will become increasingly unstable though the day as falling temperatures aloft from the west and daytime heating create 400-800 j/kg CAPE. Large scale forcing from falling pressure/heights and lift from surface cold front moving through will support the development of thunderstorms, which may organise near cold/occluded fronts moving E, with more scattered t-storms also developing in the cooler flow following the fronts. More organised storms maybe capable of producing marginal large hail (1-2cm), strong wind gusts and torrential rainfall leading to localised flooding. Surface wind shift/backing winds ahead of frontal zone could allow rotation with more organised storms - so an isolated tornado can't be ruled out - particularly across E Midlands and E England. Issued by: Nick Finnis

ECM hinting at some sort of background signal for intense LP storms: T216: Both ECM and GEM vary from GFS in that the latter pushes Scandi heights east whilst GEM/ECM even at T240 keep heights to the North/NE: GEM ECM: GFS The GEM & ECM effectively still hold the eastern block so the Atlantic hits a brick wall and any LP systems have the potential to initially deepen. ECM at D10 sends the heights to Iceland. I am again not convinced of this outcome: ...Not one GEFS member is even close to this and the mean highlights this: Could be wrong but probably another example why ECM D10 verification has been running at low levels for a while? Up till D8 ECM much like other models.

The sun has returned, making way for some fab clouds.

This is because we're measuring the temperature of the air. If you try to measure the temperature in the sun you actually measure the temperature of the instrument you're using to do the measuring, not that of the air. As all objects have differing albedos ( the ability to reflect solar radiation) then any thermometer exposed to the sun will not give an indication of the temperature you actually feel as human skin has a different capacity to absorb solar radiation than a thermometer. There are special Black bulb in vacuo thermometers ( a matt black thermometer in a matt black shield ) for trying to measure the temperature in the sun but even these are only comparable with each other and tests have shown that there can be significant variation in the readings of two such thermometers exposed side by side.

Tricky as supacell says.I think supacell has picked up on something with some post frontal troughing. Top level humidity charts for NMM are picking this up. Looking at satellite pictures I have a feeling the troughing will be much closer to the back of the front. The little bit of dry air aloft between bands of rain could enhance convection in the second band of rain although NMM is not that keen on it. Mid level humidity charts also show some development behind the front. Mid level vorticity charts suggest better destabilisation of the frontal band as it moves out of the midlands. I cannot help thinking that cloud cover is going to play a part in keeping temperatures down and think surface based instability is likely to be more enhanced with post frontal troughing. Low level Wind shear looks best under the frontal band, but there is moderate deep layer shear. Low level shear being enhanced a little by perhaps a convergence zone in the south west. There is a fly in the ointment for post frontal storms and it comes in the form of the potential state of the top level of the atmosphere. Particularly temperature which will tend to limit cloud height. Overall slight chance of a storm. Cloud cover generally limiting development during the morning so north of the midlands generally favoured. Some postal frontal heavy showers possible with perhaps an isolated one being more severe.

Models appear to be coming into line this morning and, funnily enough, if you'd averaged out the last 3 days runs you wouldn't have been far off. So no raging monsoon westerly, but no 'heatwave' either. Instead, many sunny days with decent temperatures and the odd shower, and one, possibly two days where the rain could last longer in places. Rain always more of an issue further to the NW and probably very little in the SE. FI recommences next weekend when a variety of options are on the table.

Tonight's Ecm 12z op run has all the right ingredients for another very warm / hot & humid thundery spell during the second half of next week with another pulse of continental conditions extending northwards across southern, central and eastern areas, especially the southeast. This is followed briefly by fresher air from the atlantic as a ridge of high pressure builds in from the southwest, eventually turning very warm again towards the southeast with high pressure close by over the near continent. For the time being, the weather looks warm and showery but with a mass of heavy rain spreading northwards tomorrow, reaching scotland later, warm, dry and sunny weather following for the south & east once the rain has cleared away but still the risk of a heavy shower. Early next week looks warm with sunshine and scattered thundery showers, longer term, the north west of the uk is likely to become most unsettled with atlantic weather for most of the time, however, it's a very different story for the southeast of the uk with a window of hot, hazy sunshine for the south and east before homegrown Tstorms break out again and storms drift north from france across eastern england..all in all, it's a very good early august for some of us.

Good to have you back Cap'n, your post is bang on as all your posts have been throughout the summer. With a profile like that, I don't think there can fail to be some heat drawn up sometime in the next 10 days.

Nice cell still rumbling to my north northeast..sure it was rotating aswell

More here:

Turning scary here Just heard thunder. I can't believe I just almost took a good picture of a lightning!!

Yes but it looks to be temporary and confined to the SE. Not exactly extraordinary given the time of year. Unsettled definitely the main theme from tonight's output.

Very unsettled run from the GEM this evening with multiple small LP systems and an ever-heading-southwards jet. May even be a dodgy run?

Dark clouds moving in here now

Just got this going overhead now... a random rumble here and there, the wind has picked up (a lot), but no rain. (Edit: The rain has just moderately started now *yay* - 13:30)

Yep thunder every minute here, nice little surprise

8mm of that was in 15 minutes, the other 8.6mm was over 2 hours. That was definitely forecasted. lol

Down here in the SE we'll be lucky to see a day (daytime max) under 20ºC for a considerable part of the month. Even the CET max last month only dipped to 19.4ºC on the 8th with most days above 20ºC. Today was a typical day down here - whilst a lot of the rest of the country had considerable rainfall we avoided this and had warm sunny spells with temps in the low to mid 20's. I suspect August will continue in the same vein.

Victoria winter wonder land http://www.heraldsun.com.au/news/victoria/its-a-winter-wonderland-snow-falls-in-ballarat-lorne-mt-macedon-as-victoria-shivers-through-winter-blast/story-fni0fit3-1227008140006

Scores now in and a lot of people were close for July with 3 of the 61 competitors within 0.5c. With 7 getting it spot on. nn2013, March Blizzard, hillbilly, stewfox, TonyH, Don, jonboy Well done to each of these. In the Seasonal comp, 2 players were .1c out last month, and spot on this month, stewfox and Don, so understandably very close for both. Dancer with wings is 3rd not far behind. Overall, no change in first Reef and 2nd The PIT with Don up to 3rd. Scores PDF July 2014 CET.pdf XLS July 2014 CET.xls

Until yesterday, everyone in the international community was laughing at this engine and its inventor, Roger Sawyer. It's called the EmDrive and everyone said it was impossible because it went against the laws of physics. But the fact is that the quantum vacuum plasma thrusterworks in the lab and scientists can't explain why. The entire idea that we have found something that seems to go against the the principle of conservation of momentum just seems crazy to me. But the fact that it has worked for two independent parties can't be denied. That's the laboratory speaking. Then again, perhaps both labs made a mistake. I'm sure this will be tested by the Russians and the Europeans too, but at least I'm glad we are working on it. But the fact that we may be witnessing something completely new, something that may push us forward into sci-fi territory once again, is very exciting. More here http://sploid.gizmodo.com/nasa-reveals-new-impossible-engine-can-change-space-t-1614549987

Very dry, warm and quite sunny An excellent Summer month with lots of dry and warm weather. The second half was very warm and sunny with the hottest spell of weather since July 2013. It was the driest July since 2006 (30.4mm) and driest month of any name since March 2012 (28mm) the total rainfall of 34.6mm being a mere 34% of the local LTA. There was a high incidence of early morning fog - 8 mornings although none of it lasted until 0900 GMT (the webcam helping considerably with early morning fog observations!) 1st – 2nd: Dry, warm and quite sunny. 3rd – 8th: Unsettled, some rain or showers with cool to average temperatures, apart from a sunny 6th it was a rather cloudy spell. However some very cool and clear nights with minima of 3.2c and 4.2c on the 6th and 7th respectively 9th – 11th: Dry and became warm and quite sunny after a cool 9th. 12th – 16th: Rather cloudy with a little rain at times, temperatures close to average 17th – 22nd: Warm or very warm, mostly dry with sunny intervals/ spells. Spectacular thunderstorm in the early hours of 18th but little rain, and again a little distant thunder heard 19th. Notably warm night of 18th with 17.8c being the highest minimum at this site in 9 years observations (previous record 17.2c). 23rd – 26th: Dry, hot and sunny, the hottest weather since July 2013. 28c exceeded each day peaking at 29.5c 25th. At least the nights got down below 15c through this hot spell. 27th – 31st: Mostly dry and rather warm with sunny spells. Temperatures returned closer to average to end the month, still some very pleasant weather and the only rain being in the form of showers 28th. 30th was a warm and quite sunny day. Showers in the early hours of the new month took the rainfall total above July 2006's 30.4mm and so it was prevented from being the driest July (SRB 2006). Total rainfall: 34.6mm Wettest day: 12.2mm 4th Rain days >0.2mm: 12 Wet days >1.0mm: 10 Days of heavy rain >10mm: 1 Mean temperature: 16.4c Mean Max: 22.1c Mean Min: 10.6c High Max: 29.5c 25th Low Max: 16.8c 4th High Min: 17.8c 19th Low Min: 3.2c 6th Estimated sun: 193hr Max sun: 14 hours 25th Days no sun: 0 Ground frost: 0 Mean RH: 81% High RH: 100% vs Low RH: 39% 25th Predominant wind directions: NNW Mean wind speed: 4.4mph Max gust 28mph 14th Mean pressure: 1016mbar Max pressure: 1025mbar 22nd Min pressure: 998mbar 5th Days with: Hail: 0 Gale: 0 Thunder: 2 Fog: 8 Fog at 0900: 0

Captured this massive thunderstorm over Bolton on the 19th of July Was quite a thrilling lightshow and biggest storm i have seen

31st reading should be 7.8 Hobart , Tasmania - July ( Second month of winter ) Continuing warmer than average, the 8th month in a row with a mean temperature exceeding 1981-2010 comparison. After 7 drier than average months in a row, this month was wet. Average daily maximum: 13.4 ( +1.1 ) Average daily minimum: 5.9 ( +1.0 ) Rainfall: 96mm ( average 53mm ) Rain days ( +1mm ): 7/from 12 High pressure centered to the north extended a settled ridge south, offering many mild days this month with winds off the continent, with only very brief cold changes cutting thru from the south-west. Light snow behind these changes, settling near 600m. A low pressure system forming over waters to the east brought the years wettest day on the 6th ( 26mm ), but easterly winds off the ocean are too mild for elevated snow. But at the end of the month, a series of very intense lows passing well to the south brought increasingly windy conditions, with embedded fronts bringing bands of rain, together with progressively colder air with snow descending to the 400m level on the 31st. Significant snow on the mountain range by nightfall in a wintry end to July. Extremes in daily temperature for July ( Records since 1882 ): Highest maximum: 17.5...3rd ( Record 22.1 in 1901 ) Lowest maximum: 7.8...31st ( Record 4.7 in 1888 ) Highest minimum: 10.9...3rd ( record 12.9 in 1985 ) Lowest minimum: 1.9...22nd ( record -2.8 in 1981)

No one being thick - me just not explaining myself properly. I don't think it's over complicated. The atmosphere in our vicinity is just warmer at the surface than you kight expect, having looked at the raw data. I suppose this puts us closer to 'plumes' than we might usually be. Certainly we have seen plumes to our east and hlb directing almost record high uppers into se Greenland. Plumes ain't what they used to be !

Meteorologists are saying that the snowfall yesterday was the most widespread in Victoria in 25 years: http://www.theage.com.au/victoria/melbourne-rugs-up-for-coldest-day-of-the-year-bitter-blast-in-the-afternoon-20140801-zz8ag.html Ballarat got a settling snowfall: http://www.thecourier.com.au/story/2457772/snow-falls-in-ballarat-city-centre/?cs=61 (114 photos and a couple brief videos) http://www.youtube.com/watch?v=ZMVKyo5_uSg Snow flurries reported from some Canberra suburbs yesterday: http://www.canberratimes.com.au/act-news/chilly-weather-brings-snow-to-canberra-20140801-zzlr6.html http://www.youtube.com/watch?v=4vSov9XP51I Snow getting as far north as the central ranges of NSW: http://www.westernadvocate.com.au/story/2459555/its-snowing-in-the-central-tablelands-photos/?cs=115 (17 photos) Including a light settling at Katoomba: (Source: Blue Mountains Gazette - Facebook) No snow on the northern ranges of NSW as precip associated with the frontal system did not make it that far north (as forecast).

Just heard thunder!

According to Netweather Radar and http://www.lightningmaps.org/realtime?lang=en there doesn't seem to be any newish activity as it tracks north ish over land

Mums reporting hailstones and possibly lightning?

Well there's not much hitting land by the looks of itOk well suddenly a flurry of inland activity lol...not seen any myself yet though sadly

Waiting for the thunder to start, but nothing happening! :unknw: :unknw:

Sferic showing on blitzortung close to here...time for a fag and an inspection me thinks

You are becoming known as an idiot from some of the remarks you have made in the short space of time you have been on the site. How about you try to post something constructive and model related in one of the threads?

Yep here's the 850's becoming increasingly warmer or the 2nd half of next week on today's UKMO

As the weekend surface low fills and moves away along with much of the showery rain a weak ridge of high pressure builds north which will bring some sunshine and quite warm temperatures, particularly further south. Fax for Monday along with a couple of GFS charts The first half of next week in fact looks quite decent for sun and warmth in the south and east quarter but the nearby trough sees frontal systems flirting with western and northern areas with some rain at times. Obviously details may change and no where can be promised any completely dry days. The general picture though seems to the usual split between the nw and se with the drier and warmer conditions further the south east you are, at least for much of the coming week. It does look like Atlantic fronts and rain make a more eastward push towards the end of the week with the possibility of heavy rain as the Atlantic air comes up against the heat off the continent. ECM showing such a scenario for next week end. that of course is a while away but something to monitor with the continental heat never far away during the coming 7 days or so. So yes a mixed bag coming up i think with some sun and warmth also rain or showers but very much dependent on location how one sees things over this coming period.

Significant snowfalls in southern Tasmania over the last 2-3 days, with snowfalls forecast to the lower hills later today. There's an event like this every year, two times a year if we are lucky, but it's been so mild this season that I never thought it'd come. Probably the best snow cover on the mountain range for 10 years ( going on sight alone ) with a months worth of cold rain in Hobart in two and a half days. Magic.... Very low overnight temperatures forecast for several days over inland south-east and east side of country.

Obviously some of you did not actually read the warnings, each one had words of this type, 'not all will see...but where they do occur...' Is it asking too much for those who have easy access to the actual text to take the time to read the outputs?

Deleted link doesn't work. But this one does.. https://www.facebook.com/photo.php?v=761205637275709&fref=nf Very close lightning strike..

Many a time I've looked at a photo and thought I wish I had taken that. This storm photo near Dallas, TX takes the cake tonight. Weather in all its glory. Via @RobKochWNTV pic.twitter.com/G4pJEDcihw

Probably not the greatest storm video as I didn't capture any lightning strikes on it, but here's an old one from 11 April 2008 at the University of East Anglia, Norwich, that I uploaded to YouTube. The thunder was remarkably frequent early in the storm, considering the time of year, and then there was a significant deluge of hail. That spell of sunshine-and-showers conditions during 6-15 April 2008 gave 3 days of sleet/snow and 3 days with thunder at the UEA. Found another video of mine with lightning captures from 7th August 2008, also at the UEA:

What's a thunderstorm?