Jump to content
Snow?
Local
Radar
Cold?

Leaderboard

Popular Content

Showing content with the highest reputation since 03/04/24 in all areas

  1. A nice send off around 1:30AM this morning before I go to the U.S tomorrow, storm chasing for 6 weeks. Gravesend, Kent.
    37 points
  2. A very active night of thunderstorms for southern parts, I was definitely happy I headed south to be a part of it. My evening started with confusion as I sat near to Maidstone in Kent. Most of the models were pinpointing Kent as a sweet spot but an MCS moving northwestwards from France looked likely to hit further west. After much pondering I decided to head south towards Hastings as opposed to the Kent coast. On reaching Hastings I could see distance flashes to the south, but if the flashes were to the south (and not south east) then I assumed they were going to miss Hastings and so headed westwards to end up settling in Eastbourne. From here I got to see a great show. There was little in the way of CG or IC lightning (although there was some) but lots and lots of strobe lightning out to sea and eventually right over the town. I did not capture any of the CG's I saw, and most of the IC's were directly overhead high up in the clouds. The lightning was accompanied by a constant elevated rumble of thunder along with the odd louder crash mixed in. It reminded me a bit of the Worthing storm last year in terms of lightning frequency and thunder, but did not match up to that storm in terms of wind and rain, although there was some heavy rain for a time. EDIT: Forgot to mention, some good cloud structure on the incoming storm too, which was easy to see with the very frequent lightning flashes. After staying in Eastbourne for probably and hour to 90 minutes I headed west further as lightning flashed to my west and south. I could see another storm was moving in from the Channel and looked likely to hit Brighton, and so I stopped as the storm moved close by. This one did not come overhead, it actually hit closer to Worthing I think, but was again producing a lot of lightning, and this time I could see and capture some of the IC's too as I had that bit of distance. As I was driving between the two places there was a period whereby I was in fog but with lightning flashing amongst it. An eerie experience that I have not witnessed often. As the storms rumbled away to the northwest I decided to start the journey back home. It was just after half 2 by this point and my sat nav expected me home by just before 6am. I would not end up making this as I was greeted on the way back by another thunderstorm, which was part of a line of storms that had developed and were moving from around Essex, through London and just north of the M4 corridor. I actually caught them near to the M25/M40 junction but was unable to find anywhere to stop and so just drove through them. The lightning in these storms was less frequent but I did see (not capture) a close CG and heard a huge bang of thunder. The rain was also absolutely torrential and had caused quite a lot of big puddles on the roads, making it rather hazardous to drive in. This was still not the end of it. As I continued my journey around the M25 I noticed more cells moving through London, this time a bit further north and these were also likely to hit me. I was able to get onto one moving into Watford. By now it was getting light but the lightning was still very visible, just the white/blue flashes were now replaced by bright pink flashes. This storm did not have as much lightning as the others, the energy appeared to be diminishing, but it did have some quite gusty winds on it as it moved through. I am home now and ready for some sleep! All in all it was an enjoyable night of storm chasing. It was the kind of storm chase I like, where the storms are not hard to find. There was so much activity last night that I nearly ran down two batteries on my camcorder! A great start to the season.
    31 points
  3. ChannelThunder Thanks for the heads up and letting me know that one of my photos was on the main BBC news feed, I had no idea it had been featured, it was a nice surprise. So what can be said about last other than what a crazy evening it ended up being, especially after a day of checking the latest models to see which areas stud the best chance of seeing storms, but of course there was a lot of chopping and changing going on with the various models. There were a few niggling doubts in the back of my mind which got me thinking about throwing in the towel and calling it a day, But in the end, the chance of seeing a thunderstorm was too hard to refuse, so I decided to head out just before midnight and travel to Portsdown hill, which was around an hours drive away and the storms weren't forecast to arrive until after 1am so off I set. Once I arrived, I only had to wait around half an hour to 45 minutes before lightning could be seen in the distance to the east. At the beginning it was just sheet lightning but as the storm got closer I started seeing a few CGs thrown in, but they were definitely in the minority, almost all of the lightning was of intra-cloud, and another positive was that the thunder was quite small loud. I was expecting it to be a little bit meh because of the elevated nature of the storms, but that wasn't the case at all. Anyway I could ramble on and on about last night, but i woke up at at 6:30 yesterday and haven't had any sleep since I have a bit of video footage from last night that a need to look through and edit, that can wait for the weekend, but here are some photos from The early hours of this morning. All in all, an epic start to the convective season, with more chances to come! and with any luck, other parts of the country that have so far missed out, hopefully you will get your turn in the not too distant future! SS
    29 points
  4. Eagle Eye Thanks! Keep the Faith, your time will come! This is actually The first time I've captured a bolt hitting the Earth, hope no damage was caused. For this one picture alone it was totally worth the drive
    29 points
  5. Convective Outlook️ Overnight on Wednesday, severe thunderstorms look fairly likely to hit parts of the south coast bringing the risk of frequent lightning, low-end severe hail and some flash flooding risk. Before that, some daytime showers are possible across England and Ireland with 200+ J/KG of SBCAPE possible. The daytime risk looks fairly limited on the lightning front without much energy but a few lines of showers may grow strong in Ireland whilst lacking in much lightning threat along a PV lobe. Forced ascent into clusters along convergence zones in Ireland and less organised showers across the midlands ahead of and connecting to the approaching frontal system. Generally weakening into the evening as surface energy weakens. Then the main risk is the likely linear system evolving overnight. Initially forming in a large theta-E pool east (ahead in this scenario, or rather being upglided next to the warm front) of the warm front, perhaps connecting into the warm front itself. That may weaken the western portions of the system, but only over time and unlikely to make it's effect too much before the coast. Most of the energy is associated with the eastern extent of the system where the severe risk is as well, with development into the system acting as momentum inducers. Also, bringing the risk of elevated Supercellular development given hooked deep-layer shear and strong energy. If so , then the severe hail risk is very much there because of the increasing severity of updrafts associated if a Supercell does form, as they take up more energy into the storm than non-Supercelular storms do, and given the buoyancy available, the threat for 1-1.25 inch hail is there despite not particularly amazing background signals such as the mediocre lapse-rates and the strong low-level shear. With the MCS itself, winds are unlikely to be severe but 200+ J/KG of DCAPE may risk some strong wind gusts but it's not particularly looking severe on the models. However the below cloud winds do suggest that they will take away somewhat from the hail risk. Initial development of the MCS should take place in the evening over upper central portions of France, the exact positioning still contested about. With surface storms evolving into an elevated MCS as night falls and they enter 1000+ J/KG of MLCAPE associated with the intensifying trough and moisture convergence towards the MCS as an inversion undercuts the surface-850's portion of the system and the moist but cooling air beyond the inversion takes advantage of the ejecting Theta-W plane upgliding along the warm front. Dry air entrainment into the mid-levels means that the saturation weakens past the surface towards 50-70% which is more than enough for frequent lightning to take place as the saturation signal doesn't interfere with it. Dry air forces itself behind the MCS leading to moisture diverging away from the surroundings and converging into a tight band wrapping up into the MCS itself and increasing the 850's lift and ascent occurs rapidly as this occurs in the evening or overnight depending on speed, near the northern France coast. This is where severe weather is likely to be at its strongest but some severe weather may linger into southern England as I said earlier. Exact alignment is still very poorly modelled, however, the steering currents tend to align with any Belgian or northern France developments hitting the southern coasts, with a more Belgian development perhaps having more energy to feed from but will move more WNW rather than the NW of northern French development, but that's generally the difference between the SE and southern parts of east Anglia being hit full on or relying on new storms forming further east in the channel which has been a scenario on a lot of models, likely because of the sheer amount of energy eventually out-strengthening the convective inhibition on some models, but we have decided not to extend the moderate into the SE, because of the large model split over Belgium MCS development or relying on further channel development. Convective height looks unlikely to be an issue with 10-12km of cloud height development and given the previously mentioned kinematics such as forcing and deep-layer shear, it may become even taller. With most unstable ascent being -8 LI's on some soundings. Very rare for the UK and hence the severe potential. As it hits the south coast, there is a pool of 100+ J/KG of 3CAPE extending across most of the south coast and that could well force surface storms ahead or within the system itself and an increase in strength again. Very interesting surface conditions with sea level pressure falling ahead of the trough of itself forcing that surface energy, which whilst it may take up some of the MCS's energy, this is a different pool of energy and rather the MCS is moving with it's separate energy pool so I find that an unlikely bust scenario. However, very limiting lapse-rates means that the lift is suppressing convection in this area and I don't see it overcoming the surface inversion. There are some models that are still limited in it's width development andor whether it can properly cross the channel itself. Hence why it's currently a moderate risk and a rather small one at that based off not particularly expected strength as most places hit by this, especially on the eastern extent in the south and southeast should get frequent lightning, but rather the most likely place to be hit. Given the moisture that is available, there is risk of torrential rain. and hence the flash flooding risk. Some of that may evaporative with the distance between surface and cloud base and limit that to another low-end severe risk though. The main risk is frequent lightning currently. The general movement of this appears to be along the south coast across all the way to Wales by 6 am on most models. However, weakening as they do. There may be a few re strengthening attempts in local areas based off kinematics in certain areas but that's very difficult to forecast so a slight generally covers that. That'll do for now. A very weird scenario as I keep saying. This is only my best attempt at a discussion.
    27 points
  6. A look at the 500 mb predictions THREE weeks since last did in depth check!! Sunday 28 April NOAA first then ECMWF Well at long last little signal for Upper ridging CLOSE to the UK but still very much in evidence in polar regions. Small +ve showing where the major winter trough usually resides (ne Canada/sw Greenland. Very slack flow into the far northern UK from s of west whilst almost nil for the major part of the UK. Main signal for contour troughing is around 40W and 40 N; (the remains of the major winter troughing perhaps?). By the 8-14 and the chart, to me, shows what we should expect for mid spring from the far west across into Europe? A very small +ve anomaly showing over nw Iberia. Turning to the ECMWF output for much the same 6-10 day NOAA set of charts, actually 4-8 May, It starts with the ridge just ne of Scotland extending sw with troughing still showing over ne Europe. During the period the 500 flow becomes a more general westerly over the approaches and the UK itself into Europe with the trough moving east with it showing north of the Black Sea and Turkey by the 8th May. So pretty similar really to the flow at 500 shown on the NOAA outputs. Not exact of course but one could say about on the same pages! As they are fairly similar, and from occasional peeps over the last few days, the pattern seems to have evolved fairly sequentially, I would imagine the upper flow will not be too different in the 6-10 period and beyond. This is likely to see, at least, a decrease in what seems like the UK’s own monsoon season for many to a, not completely, but drier interval. Also with some local variations (sorry East coast effects at times), somewhat more seasonal temperature values than the late January sample many have had recently. As to any specifics then possibly still more ppn for southern parts at times but I feel the ppn will be more likely to affect other areas also. Whether thundery developments develop is beyond this brief peer into what may happen. Good luck, sometimes this use of 500 MB flows does give a good idea of the next 2 weeks at that height but minor day to day variations can and do play havoc with attempts at predicting what the bottom 18,000 ft of the atmosphere can turn up!
    26 points
  7. BREAKING NEWS:- The first Nationwide dry spell , for 9 months ,predicted by the end of this week.....!☺
    24 points
  8. Convective Outlook (tomorrow afternoons risk to come tomorrow) ️ An upgliding theta-E ejection on the east side and parallel to a northwestward moving warm front should allow for an MCS to approach the south coast overnight with Supercellular activity possible mainly with feeding cells on the eastern side of the storm. Frequent lightning, 40,000 feet tall storms, some severe hail and some flash flooding are all possible. Linear development should take place after initial surface development over France evolves from surface to elevated during the evening. With dry warm air, or on slightly less capped models a warm nose, intruding at the 925hPa level, a surface inversion layer forms and without surface heating as night falls, convection is very likely to transition to elevated well past the boundary layer where significant ascent begins to be forced with the development of stronger lapse-rates and a potential vorticity lobe stretches out to help with development into a full on linear MCS. As it hits the south coast, the far eastern extent of the MCS may develop more significant potential with slightly lower LCL’s and energy pushing in more from the southeast into the Kent and Sussex coast generally on most but not all models. Some models have the eastern extent a lot further west between Brighton and the Isle of Wight, but those models are beginning to become outliers compared to most. This is where 3000+ J/KG of MUCAPE is possible for the development of these cells and the eastern extent is more likely to see frequent lightning given more depth of MUCAPE and more MUCAPE generally. The movement from northern France is northwest towards the central south to be hit first by the first part of the MCS but that appears to split or attempt to detach from what becomes the main MCS and weaken over the channel as it gets embedded into the warm front but may remain as thundery rain. That is not the main risk and occurs late in the evening. It is also not guaranteed to become much and may just be a feature of the warm front itself. Whereas the overnight risk comes next with MCS development further SSE, orientated less parallel and more head on towards the south coast moving northwestwards from northeastern France andor Belgium towards the central southern and southeastern coasts. Then it should move NW and further inland towards southern parts of the Midlands. With very lightning favourable saturation and significant MUCAPE, likely 1500-2000+ J/KG and cloud heights possibly up to 12km as it appears likely to hit central southern and southeastern coasts. This is where most risk comes from. The AROME and UKV are very strong on this occurring with pre-MCS cells forced with the change in wind direction forcing wind convergence in a line between Belgium and the SE on a few models and if this does occur, then very strong energy is available for pre-MCS cells to form and frequent lightning is very much a possibility along with severe hail especially as it eventually combines with the MCS. The most unstable buoyant layer has lifted indexes of around –9, which is extremely rare for UK risks and show the vigorousness of convection, hence the only reason why this isn’t a high risk is because of the worry over where the MCS hits. It would be in the SE but the Swiss models refuse to back down and they have been some of the best models, instead they focus on the central south with some convection extending east past Kent once it gets towards London way. A large inflow layer with significant energy and large buoyancy means that despite strong low-level shearing, hail is possible between 1 and 1.5 inches. This especially evident where cells feed momentum where they combine or if a Supercell does form. Rainfall totals could also be fairly upwards of 30mm in places and a lot of that falling in a short amount of time with a lot of moisture available. Therefore there exists risk for flash flooding. Overnight, initiation may occur north of the MCS as a forcing band develops perhaps due to gravity waves as the very tall potential of these storms gives that risk. Similarly, storms could trail behind to the south and east if the MCS is particularly strong enough. Some of which may last well into the morning because of the significant energy available. Eventually it should weaken wherever it is around 4am to 6am into thundery rain. This is where the potential weakens and any trailing cells are the main risk but only really on the UKV. There is still a lot of difference between the models but frequent lightning they almost all agree on. Along with some severe risk and generally quite significant storms. Along with the upscaling into an MCS at least of sorts on pretty much all of the models.
    23 points
  9. The undulatus this morning is quite something!
    23 points
  10. I was going to wait until the morning but there’s something very appealing about posting on the cusp of the month itself. And May is typically a lovely month of the year. Lovely long evenings, but rarely too hot, and relatively free of buggy insects nibblin’ at ya! Another motivation was that today’s 12z EPS charts are the most compelling for a fair while in terms of setting up positive synoptics for a properly settled spell. Here at day 9, the same slow moving 5-wave hemispheric pattern that has held us for a protracted spell under the influence of a trough now with clicking forward 45 degrees very much becomes our friend, with a firm build of heights shown in the anomaly shading and a most handsome ridge displayed in the contour lines, 569-576 gpm a convincing signal for a meaningful build in surface pressure. This is actually evident a day earlier with a 1028+mb high pressure at day 8 on the MSLP charts, slap bang over the UK and Ireland and there through to day 10 at least, impressive for an ensemble mean product at that range. To look beyond that stage is always a bit ambitious, but a swift return to below average pressure from there looks unlikely. May looks to be shaping up. That the projected pick up doesn’t fall for us for the bank holiday weekend is neither here nor there for the quality of the weather itself and its impact on nature. The fact that it coincides with the second week of May, at a time when the rate of seasonal warming is at its most rapid - bringing the potential, if it transpires as indicated, for a meaningful spell of fine weather as the days get long, the sun becomes strong and the land responds in earnest to the warmth - after the last couple of months in particular, will be very welcome indeed.
    23 points
  11. Keeping abreast of the models, here’s a notable pair of ECM means, in near perfect hemispheric symmetry around day 9 / 10, persistent heights reinforcing the cleavage. The sheer indecision of it all - sure to be amongst the abiding mam…oops, memories of spring 2024.
    23 points
  12. A plume of very warm theta-e 850hPa (>40c) will destabilise and track NWards across northern France behind a broader warm front tomorrow. Initially surface based, these storms will become increasingly elevated as they track northwards into southern England. 800-1000J/KG of CAPE combined with 30-35kts of deep layer sheer will allow storms to become organised & sustained as they cross the English Channel. Locally severe weather is possible across northern France with severe wind gusts, heavy rain & large hail associated with possible supercell storms and a broader tornado risk. For the UK, the elevated nature of storms suggests a reduced severe weather risk however heavy rain & frequent lightning can be expected. There remains a lot of model variation on where these storms will track. SE/CS remains the most likely outcome with landfall probably east of the IoW but west of Folkestone as a rough estimate. Some modelling (UKV in particular) suggests a much further westward track into SW England/up into Wales but this remains on the extreme western end at the moment with models such as AROME/EC remaining consistent with a more eastern track.
    22 points
  13. Hey guys,...you missed me!!! i see tentative signs of things settling down as we go through mid month,...i asked mystic meg,yeah right but i will try to be informative... latest cpc looks predomantly south of west so milder than of late how far can the Azores rigde push north to settle things down is yet to be determined so stay tuned P.S ,i have missed so much in here that i will not go back on reading all the post's and the reason beeing is that my OH is ill and could end up in a wheelchair soon but i hope not,she is suffering ATM from (not comfirmed) MS or sciatica,so bare with me and i will post when i can good night all and take care,you don't know what is next around the corner,...just saying P.S next up,...summer is coming,i am fed up of all this rain it is crazy,...a flip of fortunes to better weather can't come soon enough. good summer to all.
    22 points
  14. 21 points
  15. A storm passing the south end of Milton Keynes birthed a weak funnel cloud, lasting for a few minutes just before 5pm. Rotation in the cloud leading up to it was very evident!
    21 points
  16. Three things stand out this morning from gfs. A drying trend nationwide, that must be the most important thing that stands out. Secondly, a chilly airmass enveloping the UK, bonus plenty of sunshine, especially southeastern Britain. Thirdly, Frost ,will be problematic for just about all nationwide. A lot to cheer about, now the rain train is coming to a halt ,some pleasant Spring like weather on the way, ,no heavy rain , No gales , and bright cheery weather to be had , what's not to like about that! ☺
    21 points
  17. Quite possibly an elevated Supercell and some of my favourite photos I've ever taken. It was incredibly menacing as it moved it. Lots of striations showed themselves occasionally.
    21 points
  18. Blimey. What a night... Whilst it wasn't the most severe storm I've ever seen, the lightning frequency and longevity of it was truly something to behold. The first flashes became visible at around 22:20, with the initiation of the new cells ahead of the french MCS. It then quickly ramped up in frequency, reaching an astonishing hour long peak between 00:30-01:30. In that time frame, the sky was lit in a solid arc from the WSW all the way to the ESE, with additional flashes emanating from outflow cells that were in inland East Sussex- We were effectively surrounded. Rudimentary counting between flashes became futile, as each flash had less than a second between them. Most of the time the flashes were IC, but occasional CG's and C-Cs provided louder booms and more substantial camera footage. Some amazing structure was visible for a short while, with a long and tall roll cloud present within the line. Another thing we noticed was the constantly shifting wind direction and brief fluctuations in temperature; It was apparent that the storm had strong inflow, and as it moved closer there was a brief surge of outflow winds too. The first arc moved WNW over Eastbourne and surrounding areas by 01:45, and after that another 'finger' of rapidly organising convective activity seemingly followed the same path, with almost the same intensity. This slowly trundled it's way towards Eastbourne and beyond, and by 02:30 only distant flashes and cloud top reflections remained. We (me and @Electricmumma) then called a taxi home, tired but smiling! Overall, based on different factors, this storm gets a rating of 8.75/10 from me. Could have been much closer to 10, had the beefy looking cores on radar gone overhead rather than skim the coastline. An extremely impressive display for so early in the season, and the lightning amounts were up there with some of the greats in my lifetime!
    20 points
  19. This is at Norwich at 3.45pm just had some big lightning and hail from this heavy shower.
    20 points
  20. Looking at the next ten days, which cover the middle third of April, t’s good to see the relevant part of the annual cycle, in the form of the springtime waning of the PV, well underway. It is happening a bit later than the last couple of years, but is striking nonetheless, here on both the 0z ECM operational run and ensemble mean, day 1 - 10 animations, the PV very much on the wane, being nibbled away by evolving mid-latitude ridges, with the core PV diminished and returning from the Siberian Arctic to the pole. This leaves us with a solidly meridional 5-wave hemispheric pattern by day 10, shown nicely on the op and mean anomalies, ridges by then through western North America, up through the eastern seaboard, Western Europe, Kazakhstan up into Siberia, and the far east of Russia. The picture for the UK and Ireland alternates from seeing a shallow ridge over the next few days, to being under the influence of an active low pressure system passing through with the trough around days 5-6, before the arrival of a better amplified ridge by day 9-10 as the more meridional pattern firms up. Day 10 provides a convenient juncture for the UK and Ireland for showing the potential for something more settled getting a bit further north to be more widely shared, op and mean again. However, it looks very much like it’s a snapshot in a slow but steady revolution of the 5-wave ridge / trough pattern around the pole, with approximately 4 days appearing to be the current phase for the ridge to trough transition, hinting at a period of drier, brighter spells of 3-4 days alternating with more changeable spells of 3-4 days. A much more normal and much more pleasant a pattern on view as spring more clearly shows its hand.
    20 points
  21. Close up of my only CG last night as far as I know.
    19 points
  22. A cracking set of runs this morning. Once we get the weekend trough out of the way, it's high pressure all the way through the rest of next week. GFS: ECM: UKMO: GEM:
    19 points
  23. I'm not a mod, but if people can refrain from using the word 'bust' (if actually applicable) until at least the scheduled time of the storms, that'd be great! Just a little pet peeve from previous recent events...
    19 points
  24. Convective Outlook️ Wednesday (day 2) Wednesday night a shortwave trough advancing east of a frontal system should allow for storms to form over northern France potentially moving NW into southern parts of England. There are however uncertainties over positioning still so much so that they could instead be centred over Belgium and move into eastern parts of England, slowly weakening moving NW/W into the midlands. This is limiting the confidence over where to place the risk currently given lots of difference between the models. However, away from the modelling issues, this a high-end potential event but with a few bust risks as most do to be discussed later. A theta-W ejection from mainland Europe will either be centred over Germany and move NW into Belgium or further west on the border between Germany and France and hit northern France, and storms will likely initiate in one of those two areas. As they do, large upscale growth by deep-layer shear is likely into an MCS is likely with forcing being very high compared to a typical risk becoming very favourable for clustering into a system of storms, unless there's a downtrend in the forcing, this seems a very likely solution. Given the high theta-W airmass and surface inversion that appears to hold in place, a transition to elevated storms towards the evening as surface energy over northern France and/or the border and Belgium area weakens appears likely. With the remaining mid-level energy appears to be high as these storms move into a new area of what appears to be separate energy held in the mid and upper levels of the atmosphere slightly further north in the late evening. And this is where the transition upscaling into an MCS appears likely as well. The initial surface based convection over land becomes its own system as the trough forms with dry air undercutting the trough and driving the band of moisture convergence, influxing energy towards the trough itself and taking in energy from the surroundings. It's a very important part of the MCS development and also the potential to survive the channel, without the moisture convergence becoming centred around the developing trough, or becoming centred too early, it won't reach the UK. Currently most models are adamant that despite the multitude of scenarios with timing possible, the trough develops just late enough into the evening for the MCS to develop as an elevated MCS, rather than surface based and what shows that is that on some models without the whole storm being forced along the trough, the parts not on it fall apart as the surface energy weakens. This trough also brings in significant ascent beyond the boundary layer with buoyancy more typically associated with surface storm days in the height of summer with -5 LI's at the 850 hPa height. Therefore any convection could well force a vigorous updraft capable of significant hail just past an inch in diameter but mostly limited to that given the strong low-level shear in place that will take away some of the hail's strength. So despite favourable hodographs with a strong inflow region, along with widening updrafts because of combining cells and energy strong enough for quick updraft speeds, the hail is still limited to the lower end of the severe potential. This forced ascent should also help with quick upscale growth once the shortwave trough helps rapidly increase it and therefore most surrounding cells will be brought into the MCS likely as constructive mergers for momentum inducing events, so watch out for larger hail and more significant storms where these mergers take place, should the storms reach the UK (assuming they form which looks very likely despite the capping in place) and a small tornadic chance but the elevated nature of the MCS will likely keep that very minimal. Surface energy may still linger crossing the channel on the eastern side of the trough, along with strong deep-layer shear becoming more guided towards a hook there as well. This has lead to 50+ J/KG of 3CAPE with 1000+ J/KG of MUCAPE possibly forcing a Supercell for a time on the eastern side of the MCS or detached from the MCS itself, risking stronger hail and again a small tornadic chance. There could also be an elevated Supercell linked in with the actual MCS itself. The hodographs are fairly favourable for that, the actual MCS upscaling is more of an ascent nature than a speed shearing nature. 400+ (m^2/s^2) of SRH certainly shows the significant potential of this event but that depends on the shape of the hodograph which varies a lot from model to model as they tend to do at this point in the forecast. The higher end do have a very Supercell and hail favourable highly streamwise flow with a large inflow region though. However, there's still a weak tornadic potential with the surface lift just not being conductive on almost all models as the surface based Supercell looks very unlikely, just a small potential, most likely elevated if one does form. Lightning risk does look to exist fairly well with this, saturation doesn't seem much of an issue aside from a few areas on soundings. It's not great but strong energy and often I find lots of momentum builders as there are in MCS's can counteract that as long as there's enough energy, there does seem to be some sort of threshold past about 1,000 J/KG where the saturation can become less of an issue. This is mostly based off experience and modelling though. Saturation does appear to be quite good on the central southern coast on the models that go for the northern France initiation and also the ones that go for a Belgium initiation, hence that is the highest risk for lightning at the moment on the models. The more widespread lightning event currently modelled appears to be the Belgium initiation that the ECM is currently adamant on, but an uptrend in the northern France risk wouldn't take much to do the same. There's a fairly high-ceiling for this event, but it's still complicated in it's expected evolution and the surface based storm transition to elevated timings. Saturation could also become more of an issue if the models start trending that up.
    19 points
  25. Tonight we seem to not have a great outlook in the short to medium term. After we get the current cool cyclonic period out of the way over the weekend (unfortunately a pretty dreadful one for most), into early next week we have a warmer pattern developing for Tuesday and Wednesday, but nothing particularly impressive. Raw maxes of 17C on Tuesday and 20C on Wednesday, perhaps in practice 18-19C and 21-22C. Exact figures probably dependent on timing of cloud and rain. Wednesday possibly a new warmest day of the year, but nothing out of the ordinary for the start of May. However, further into May we have a significant pattern change on the GFS tonight. In the extended range, the 12z at around day 12-14 sets up a high over and to the east of the UK. It's not the strongest, but especially eastern areas you would think stay mostly dry under that. The temperatures are nothing spectacular to be fair as the core of the resulting heat plume is away to our south, but a number of days with very pleasant afternoon temperatures in a row. Of course, this is a long way off. In terms of the ensembles, the GFS still isn't that interested, but it has mostly erased the cooldown after the initial warmup around the middle of next week, and a bit of a signal to follow the GFS OP later on to a lesser extent, so I guess already an improvement on what was showing 2-3 days ago. Summary Still a long way from any sort of heatwave or anything particularly notable, but the pattern on the GFS 12z OP would be pleasant enough. Certainly a welcome improvement. From a personal perspective, I'll be paying close attention to forecasts for May Day and the following week (commencing 6th) as I've booked it off work.
    19 points
  26. It seems some are in denial. The mean for Manchester has highs barely in double figures for most part. It’s certainly a cool outlook with winds frequently coming from northerly direction with cool air aloft. A bit milder this weekend with high covering UK briefly, then it looks to re-centre further NW. it’s a very poor outlook if you’re looking for warmth. If only if it was winter comes to mind.
    19 points
  27. Just like to the 10 days before Easter the models were in full agreement of a deep Atlantic low just to the west of the UK, now we have solid agreement of an Atlantic high setting up to the west, and maybe shifting east to sit over the UK. Nothing particularly warm in sight at the moment but definately an end to the constant deluge is now pretty much guarenteed...Thank God!
    19 points
  28. The GFS 00z ensemble has now fully eliminated the cooldown in the mean - temperatures now looking consistently near or above average. Looking at precipitation it seems like we'll struggle to keep things entirely dry though - a fair few precipitation spikes. But certainly nothing there screaming extremely wet pattern - the mean rainfall is pretty low which suggests it'll be dominated by infrequent showers rather than heavy frontal rainfall. Sea level pressure tells the same story as well - mostly on the rise after this weekend's dip. All in all - not too bad. It's also interesting how the number of warm outlier runs is beginning to increase again - an odd run taking the temperatures above 25C, like P20 of the GFS, with a broad area of high pressure over the UK and centred to our south east. Also looking at the dam lines a very strong high for the time of year - the 584 line into the SE of the UK. By the end of the run some very hot air just to our south as well, so the pattern may have continued beyond the end of the run. The first heatwave run of the year - taking into account a usual under-read of 1C or so many areas would surpass the Met Office heatwave thresholds with this. Again, only one option and a very long way away, highly unlikely to verify. But as many of us have been saying we need to be on the lookout for these very warm outliers and see whether they gather any further ensemble support. Most of the time they do fall away again but sometimes they keep gathering momentum...
    18 points
  29. Some from this afternoon. A fab day for some cloudspotting, about as classic of an April sunshine & (hail) showers day as it gets. Although a little chilly for my liking, the very strong sunshine makes up for it! Also some mammatus looking at the Coventry Airport cam when I didn't have the chance to capture them:
    18 points
  30. As the great man himself promised, Kathleen is being taken back home again, to be reabsorbed within the PV by day 5, here on the 0z ECM operational run. As a result, for the UK and Ireland, a vastly improving picture over the coming week as heights build northeast from the Azores, temperatures picking up by the end of the week for a while too if the T850s are anything to go by. Before exiting east, Kathleen ejects some energy westward to help the next system along, this one passing east further north through Iceland, to set up over Scandinavia from day 6 through to day 10. The bulk of Kathleen has by then rejoined the PV from the Siberian side, helping it pivot to be elongated down towards the Norwegian Sea, fuelling the dropping of the trough down through Scandinavia, bringing the UK and Ireland into a cold northerly flow for several days. After this rather dramatic phase (following three inches of snow in west Wales last week and three days of gales in the west of Ireland this week!), Kathleen looking to help ultimately deliver something for everyone - a storm, briefly something a bit warmer, followed by some clear Arctic air and the possibility of a quieter, more standard meridional pattern as we head into the second half of April. So I guess it’s only fair to leave the man have the last words: “And when the fields are soft and green I will take you to your home Kathleen”
    18 points
  31. Convective Outlook️ During the afternoon, a convergence line will form within the SLGHT zone forcing intense showers & thunderstorms to develop. Instability is transferred to this area from the early hours intense storms, with cape sitting around 500-1000J/KG. In the late afternoon/ early evening, thunderstorms should start firing up bringing frequent lightning, hail & intense rainfall. We are slightly unsure how todays line of storms will form and how much lightning there will be, however if these storms do form, they can bring frequent lightning.
    17 points
  32. Thank God the 00z runs are moving towards HP having more influence from mid month. It's hardly stopped raining since October in the North west....absolutely appalling 6 months of Atlantic dominated weather.
    17 points
  33. Just looking at this morning’s clusters T192-T240: There are six clusters, spot the odd one out! Clusters 1,2,3,4,6 all have a ridge of high pressure taking hold in the region of the UK. Cluster 5 - which contains the ECM op and control - does not. As it only has 6 members, I think I’m inclined to discount the ECM op solution this morning in favour of the other models, supported by most of the clusters.
    16 points
  34. Little point ducking the issue. A quacking weekend in store… 0z ECM op for day 4, as another low pressure system finds us with impressive timing! Further ahead, some more positive signs - once we start seeing this type of “super-meridional” pattern - ambitious building of heights up through the Atlantic and more spectacularly, through all the S’s - Sahara-Sweden-Svalbard-Siberia-Seguam like here at day 6 on the 0z ECM op… …it’s only a matter of time before we start seeing the trough becoming over-extended with the cutting off of the low at the base of the trough, it sinking south, the heights linking up through the UK and Ireland like here at day 8… Yes, add Skegness and Sandymount to your list, spectacular super-meridional S thing! After that, a weaker version of the trough tries to reassert itself from the northwest, which the GFS op has been keenest on, though looking at the 0z ensemble mean, the pressure never really falls away again, a steady rise to a respectable 1020mb for Birmingham by the end of week 2… …which is consistent with the ECM charts and the pincer movement of heights weakening the polar trough at its stem - so though nothing wall to wall by any means, the chance of a somewhat more promising setup emerging into early May. I’ll post again around then. All the best.
    16 points
  35. Shiver me timbers! Looks like we have a retrogressing high before our very eyes, ha ha haar (and other pirate noises) - even before it’s properly arrived. Whether ‘twill be as shivery as 6z GFS op at day 9, where it withdraws far enough to the northwest to allow a proper cold blast down the frontage with some snow a fair way south, and settling on the hills… or holds close enough nearby to keep the old lunger a bit further east like on the 0z GEM op at day 10 (beware that sea serpent beyond the pole, haar)… the retrogression and European trough are definitely looking to be features of week 2 - ‘tis here too on the 0z EPS at day 11. Aar. The CFS weeklies (weeks 1-3) show the Euro trough by week 3 being reinforced by its maritime buddy that’s come romping through the Azores in weeks 1 and 2, while to the north, the Atlantic heights hint at wobbling back east, a tad back our way again… …the big concern for us island landlubbers looking for something to warm our jellies is that rather than a generally quiet but cool outlook, the pattern in the event all heads just that bit further north bringing us back into chilly cyclonic influences that just judder your rafters. More pirate noises….
    16 points
  36. Eps mean is strongly keen on higher slp in two weeks which is v notable at such a range gefs not too different About time !
    16 points
  37. The GFS 10-day accumulated precipitation shows a bit more of a traditional NW to SE split tonight. Still some very high totals for W Scotland, NW England and N Wales, but away from those areas, it really doesn't look all that bad, certainly compared to recently. As we move towards the longer range, it's always a dangerous game making any predictions, but the mean signal is still for any cooler NW / N interlude to be on the short and not too severe side of things. As a final note, worth commenting on that absolutely insane GFS control run in deep FI. Couldn't let it go without saying something of course! At around day 12, things look relatively normal - chilly in the north and relatively mild in the south. But what's that over North Africa? Stepping forward to day 14, the plume launches northwards. And this is where we end up at day 15. 20C isotherm just clipping the south coast. 25C possible in London, over 30C in France.
    16 points
  38. No comment on the models this morning? In a nutshell, we have a nasty little feature tomorrow that'll give many of us cool, windy and damp weather. After that, pressure builds to the south and SE, bringing sunshine and temperatures up to 20c across these areas by Thursday and through the weekend. The ECM then makes more of that NW'erly blast, bring cooler temperatures again by early next week, but the GFS doesn't make too much of that and quickly rebuilds pressure from the west, settling things down nicely. The UKMO only goes out until next Sunday, but looks similar to the GFS in that it looks a lot less primed for a NW'erly in the way that the ECM shows. Step by step, this is what each run shows for tomorrow: Then later this week with the build of pressure to the south and south east: Then towards early next week, here's how each of them deal with the chillier NW'erly: ECM: UKMO only goes out to Sunday: GFS - keeps any NW'erly very brief, with a quick rebuild of high pressure: What about the means: Less bothered about 850's at this stage, so looking at pressure, the GEFS has a short dip before pressure builds again by the middle of next week - graph is for London: ...and for Manchester: The ECM mean unfortunately is less keen on a quick rebuild of high pressure and keeps any rebuild fairly weak: So we can confidently say that tomorrow looks awful for many, then much warmer, sunnier and drier across the south/SE midweek onwards and into the weekend, less so further north and west, then uncertainty over the potency and longevity of the NW'erly and how quickly and to what extent high pressure rebuilds into next week.
    16 points
  39. Attempting to piece together (as we are inclined to do!), emerging trends of the outputs from different models, here the 12z GEFS and UKMO at day 4: And then, taking it through to day 7: That is one very welcome surge in heights from the southwest early next week, resulting in a 1030mb+ high pressure cell making a visit on the UKMO. A tad optimistic perhaps and probably not that long-lasting in the event, but the contrast is striking and very good to start seeing all the same. Have a good one.
    16 points
  40. All the best looking strikes from his stream in one post. It seems he was in Worthing instead of Eastbourne. Then drove west to Portsmouth I think last (4 pics). He's still streaming but i'll probably be heading to bed now. Night all!
    15 points
  41. Well after the mixed bh weekend where there will be rain about but also some sun to be had the signal from the gefs for settling down next week still strong from the 0z this morning... ..quite a pronounced high there.. ..although no heatwave there is scope for low twenties in favoured spots i would think.. ..the op going for higher pressure lasting a bit longer... ..as usual orientation crucial...ecm 0z op while also showing the high its placement not as favourable.. ..although south western areas would do ok temps generally bit lower..gfs 850s and ecm.. ...nice to see high pressure on the charts after what seems ages...while the upcoming bh may well be disappointing for many areas ( as per bh usual it seems) ..we can hopefully look forward to some fine or better weather after for at least a while with the usual caveats of hp orientation to be confirmed... ...misty here this morning but the air feels warmer and...kinder...have a good day...
    15 points
  42. Some great posts in here today and it nice to see the thread come alive so early in the season! Also thanks @Eagle Eye for your amazing contributions to this thread, the effort you put into you forecasts is much appreciated and I'm sure I speak for many of us on here, good luck for tomorrow night, but not too much of course, as that would mean you'd be stealing CS England's storms but seriously, I hope many areas can join in the fun tomorrow if all goes well.
    15 points
  43. It looks like there will be snow on Saturday, in my area and in part of the rest of Finland. Next week more snow or sleet is perhaps coming, this time of the year, it is not necessary anymore. Hoping that Summer months June/July is something like showing reanalysis, not like lastest summers. Sorry My bad english.
    15 points
  44. If you’re talking to me at least @ me thanks. In what way I have done that? All I’m saying temperatures are indicated to be well below average for late April, no one has mention snow and freezing temperatures and what can be expected at this time of year. You said about me being antagonistic, I think you should look at yourself, all you do is purposely try to undermine messaging, if anything cool is mentioned, it’s a repeated pattern from you. It’s as if it upsets you personally, I find it very odd it is just the weather.
    15 points
  45. Some pretty intense hail showers have been hitting here
    15 points
  46. Wet snow falling early this morning at 2c not settling but inland on moor road a few inches at 0c according to car. Saw one car off road bu.mried in bushes with lights still on.
    15 points
  47. ECM settles things down across the south from the middle of next week: ECM pressure mean for the SE looks OK, better than it has been for some time, at least temporarily: GFS similar: GFS mean also looking good later next week for the south:
    15 points
This leaderboard is set to London/GMT+01:00
×
×
  • Create New...