Jordan S

Whilst higher pressure than we've been use to for last week of April is still favoured along with occasional brief wetter conditions especially from our south, there is obviously a lower possibility that the evolution below takes place which I was going to post on yesterday but got completely sidetracked, would take us to square one and my previous posts then being too ambitious shall we say of drier weather than we've been use to by then. Thankfully the synoptic pressure pattern being low though around 30% Not worth worrying about at this stage, with a fine few days to come further south at last in the meantime. Will try and do an in depth update later in the week, especially in regards to late April, but mental health isn't doing me well atm so may post less often. Take care.

Afternoon Just want to quote a couple of parts of my previous update for this upcoming drier trend around mid month, the outlook is fairly close to what looks like transpiring as we head past the 11th. Definitely looks somewhat better than we've been use to for a long time.. High pressure back on the scene, but unsettled interludes as expected, particularly in the north, but now with conditions not particularly warm at first and rather cool at times in the north/northeast with wintry precipitation on some high ground occasionally, driest weather tending to be in the south/southwest through the mid month period. Now as for last week of April onwards.. taking a snippet from my outlook for the end of April and through May.. I stick by this quoted post of mine below for now, It is more likely to be drier than we've been use to with higher pressure a more frequent visitor to the UK, but the potential for occasional but very wet/thundery spells from our south/southeast, causing potential flooding for brief periods. We'll see how this plays out.

Just a quick one today Yes @WYorksWeather A surge of unusually high upper air temps for Friday/Saturday in the southeast/east of England. An impressive low pressure system for April set to move north to our west later Friday and into Saturday party responsible for the surge in upper air temperatures, the low spreading heavy rain northwards through western and northern parts of the UK where it will be cooler, with over 3 inches possible in some areas exposed to the southerly wind, southern and eastern England generally drier though some outbreaks of rain could occur at times especially from a cold front on Saturday, very windy with gales in the west and north. Quite cloudy in the south and southeast of the England with surface temperature in the east of England upto around 19-21c in any sunshine, a bit less warm in cloudier parts of the east, though these drier conditions brushed away eastwards by that cold front, some drier weather at times on Sunday before a low pressure system brings more rain for many at times early next week, thunderstorms possibly following behind weather fronts into the south of England with the risk of hail.

Quite extraordinary model outputs atm, for example an ensemble model that I'll show below as a gif from last night of many models together, shows the UK being a low pressure magnet for its entire 16 day run, it's a typical synoptic that has taken place for a long time now. In these set of charts, barely a ridge of high pressure over the UK for the majority of the times with no high pressure cells setting up over the UK even for several hours, never seen that on this chart before, it's clear that unsettled or even at times very unsettled weather is likely to feature upto 10th April at least, for the majority, with confidence rating of 90+% of this occurring, less unsettled possibly at times after 11th-12th April particularly the south with increased temps for southern UK, but by and large higher pressure although closer to the UK to our south/southeast, not having much or any influence in the UK weather in terms of drying us out for any length of time before and over mid April and that hasn't changed from previous thoughts when I did my previous post. Part of the reason this unsettled weather has continued so long is partly due to a slightly self feeding mechanism this wetter period we are stuck in and have been stuck in for several months has produced. Saturated soils and landmass generally promote more instability/lower pressure, whilst bone dry ground will generally have the opposite effect without the presence and influence of wind direction shifts/water sources/significant background synoptical changes further afield. Works a similar way to heat domes/ frozen landmass under snow cover. It's uncommon to see sudden flips from long lasting extremely wet conditions such as the one we are in currently, to fairly or very dry sadly, though certainly not impossible, and what tends to happen if a drier spell is likely to develop for a more significant period of time (from natural variability of weather inevitably at our latitude and changes from further a field that are very pronounced) is more and more ridges of high pressure are "thrown" over a landmass particularly wet more and more frequently over a period of several days or weeks, this largely applies to areas such as the UK where synoptics can move along very quickly. In theory you'd say the longer this wet spell continues then bigger and bigger shifts in weather patterns further afield would be required to shift the pattern enough to change the weather conditions to dry but many smaller scale things changing at once would of course help produce a similar outcome, of course the pattern will definitely change to something dry and that's why as never ending as these lows are, there will be a shift to a more typical UK weather pattern or sustained high pressure, but perhaps not for a while yet.. If I am to really take an educated guess as to when this relentless barrage of low pressure systems may begin to change to a more significant and longer term degree and move more to our northwest and produce less intense weather fronts and higher pressure have a more significant frequent, larger influence over the UK, then I'd be inclined to think last week of April onwards, BUT like I said above from the 13th-14th April increasing incidences of drier conditions perhaps presenting themselves especially for southern and eastern areas, with unsettled weather more likely for the west/northwest of the UK by this time, for a short time, and that does link to my previous two updates suggesting the possibility of this outlook for this time.. BUT I mean less unsettled overall, with a few more drier days, not likely to overall be settled and dry nationwide for any more than a day or 2 I'm afraid given the lows continued proximity to the west of the UK, but perhaps somewhat better than we've had and will have in the next few days to 10th April if that plays out for mid month onwards. The latter part of April and especially into much of May, (may) generally be more likely to have more frequent occurrences of dry or drier days than we've been use to for some considerable time, partly given the time of year and warmer temps (higher evaporation rates) but I wouldn't be surprised to see frequent quick breakdowns to thundery/wet conditions particularly from our south/southeast, with the potential for these to cause further flooding problems where they do occur and that does seem more likely before it clears up for a few days at a time with warmer temps, indeed this thundery and overall less unsettled synoptic pressure pattern over Northwest Europe and UK is more realistic and in fact could easily remain for the Summer period in its entirety, but if this where to take place as per what I'm suggesting, then we would be more likely to have a thundery/ fairly, though not very or exceptionally unsettled first few weeks to meteorological summer, certainly less unsettled than what we've had upto now, with a shift to a much drier pattern later in the summer with higher pressure being the dominant player. As for temperatures more uncertain, could be much cooler than average or warmer than average tbh, I'd favour a cooler first part to summer in the south especially, then warming up later in summer to above average, perhaps significantly so. Whatever happens this unsettled spell will break at some point obviously, small chance we see a sudden flip to high pressure dominated dry and warm conditions late April onwards but I don't think so, looks like we will have to wait for a few weeks yet for any sustained long lasting high pressure systems over the United Kingdom. For the next 4-7 days though, very wet and that has flagged for a long time on my posts so not worth going into too much detail on this but 30-50mm is likely to accumulate widely, especially parts of England and Wales at first, locally a bit more, and upto 150mm on mountains. Take care.

It's rather clear now that this synoptic possibility quoted above that I deemed slightly lower likelihood around 40% is closer to the mark for the second week of April. Wetter conditions continuing, especially further south and then western UK later on, confidence rating in this being 70% A widespread drying trend from the northwest is less likely now for week 2 of April as a whole, would deem this 10% Upto 10-11th April, but still expect possible further wintry showers/longer spells of wintry precipitation on occasion in north and still it overall looks less wet than south at first, the wetter conditions favour the northwest/west for a time later week 2. Potentially still warmer by mid April in the south as the blocking shifts around slightly with a southwest to northeast elongated trough/areas of low pressure over us and especially to our west/southwest with higher pressure still over close to Greenland, heights also build to our southeast over central Europe but any drier than average spell over the UK and northwest Europe most likely from end of week 2 at the earliest, most likely for far north/ and or the south/southeast of England if it where to happen but the signal only loosely favouring a proper drying trend by then for now, with unsettled weather the main theme before then. Causing potentially large rainfall totals. Take care.

Models are in good agreement over the deep low and the positioning just to our west and that's been the case for days. Anyway.. The outlook quoted above from mine from the 18th and indeed the other updates I've done recently is largely very much still accurate in regards to the general synoptics and weather conditions expected for Easter and then through first week of April.. most unsettled central/southern England with generally drier and slightly colder conditions in the northwest in early April with wintry precipitation with high to our northwest, that is still most likely and that's been a theme in my post updates from the 15th March! although could be some longer spells of rain/snow for Scotland depending on how far north frontal boundaries reach at times, wind direction largely expected to be as my previous posts have mentioned, more northeasterly in north for a time and more variable in south with thunderstorm risk and very wet weather distinctly possible at times here with only very low risk of wintry precipitation on high ground in central/southern UK. In terms of Easter day itself it may actually be mostly dry in some areas with sunny spells bar some heavy showers and areas of cloud in some areas, wintry precipitation in parts of the north. Again an increased chance of drier conditions more widely through second week of April courtesy of higher pressure to our west/northwest moving in, but model output itself for this evolution and signal is rather weak at the moment. So as for confidence of said outcomes.. Confidence rating of a colder and less wet transition in north/northwest and unsettled first week to April overall for many further south, especially in south with temperatures around average/slightly below here 90% Confidence rating of a lengthier drier spell for the UK as a whole through second week of April courtesy of those heights to our northwest well advertised by me in previous updates, with temperatures around average at least at first? 60% Around mid April 13-15th and their are hints we could see a synoptic pattern evolve that results in our first generally very warm spell over England and Wales accompanying a lingering possible drier spell in the south, with a south/southeast wind, this quite typical of how blocking highs can align themselves after a colder spell but any particularly warm spell unlikely to last beyond a few days before either wetter, cooler and windier conditions may move back into southern or western UK or colder air is filtered within an anticyclonic drier pattern over the UK. In fact by then so around and even after mid April a more traditional synoptic pressure pattern for the UK may try to finally take full control over the UK building heights to our south with the Jetstream returning to the usual northerly positioning with variable conditions day to day in north, wettest northwest/drier south but too far out for any more detail on that. A lower chance that southerly tracking lows continue right through the second week to mid April and beyond, continuing the wetter than average theme for southern UK in particular and continuing the exceptionally persistent pattern that has effected the UK since July last year for the most part, worrying if that where the case and would raise questions as to just what this could mean for the rest of Spring, especially as I don't expect the wet weather to continue all the way to mid April and beyond, but the first week of April definitely likely which is problematic in itself, again especially in southern UK at times, but for those wanting late season snowfalls then there is interest in that regard further north if the lesser likely outcome further into April materializes, as well as the expected wintry precipitation at times in north early April mostly in form of showers/ especially high ground. Take care all.

Ecmwf showing the slightly warmer air signal attempting to move into the south though it’s very unsettled as expected so just slightly warmer rain This drier northwest UK likelihood I mentioned also certainly still looking a decent possibility with higher pressure trying to move into northwestern areas as we go through the first week of April but central/southern and southeastern areas still likely to remain more unsettled and even in the north, probably not completely dry atm. The drier signal I still believe is slightly more likely than not through the second week of April more widely atleast for a good few days with more sunshine than we’ve been use to although probably not warm at first… We will see.

Summer8906 I would say any lengthier drier spell from a high coming from north/northwest would be most likely given the overall pattern likely to take place but wouldn’t rule out a ridge from the southwest on occasion but this probaby further into second week of April because even into early April low pressure probably dominating our part of the world. But the hint I mentioned of perhaps more widespread drier weather in the second week of April from yesterdays post being from the exact evolution I’ve just said above let’s hope those slight more lengthy drier conditions do turn out correct for the second week.

Cambrian Really good post Cambrian I was also about to comment on the comments mentioning models only reliable to 5 days or 3 days etc, it’s actually more often than not a rather inaccurate statement otherwise for example I wouldn’t bother with my outlooks past day 3 but I see why they may think that with operational runs (excluding the ensembles) There is genuinely high predictability (if you are knowledgeable in reading and interpreting the model output) at days 6-10. Less reliability between days 11-15 ofcourse but the broad pattern has more often than not been accurately estimated/forecasted that far ahead and enough that you could on average get correct at least 25% of the time, I think the furthest ahead in time “ceiling” of being able to forecast (computer models/ human input) area of local parts of country precise details being around day 8-9. With relatively accurate broadscale hemispheric patterns and what they could entail for our part of the world excluding teleconnections being around 3 weeks time. For anyone interested I highly recommend those Noaa 500mb height anomaly flow charts that are posted every now and then, really useful forecast method I’ve found, even though I’ve only started looking at them as part of my outlooks in the last few weeks, they aren’t 100% accurate but they are accurate way more often than they aren’t but more for a general overview than any specifics in a location of course and that’s for the human to take apart and forecast from it. Easter still looks most likely unsettled in central/ southern UK and a bit colder and less wet further north with snow risk (probably mainly on high ground).

Morning, Just a quick one today, must of been half asleep when I typed this part there are north/northeast winds albeit brief along with colder temperatures, though nothing unusual with a few wintry showers in the north/northeast possible, especially on high ground. The latter frames of the models recently are typical of the extensive northern blocking that is set to build and dominate further, with any brief spells of drier weather most likely in the north/northwest during Easter and indeed early April as said previously, though unsettled is the main theme for the UK as a whole, cool for the time of year out of lengthy sunshine in the north with wintry showers a continued possibility but quite typical for the time of year, very unsettled conditions still more likely to move in from our south/southwest over Easter and beyond for southern and western parts in particular, only a remote chance of any snow here, just potentially again very wet with slow moving fronts, northeast/easterly winds especially in the north a high likelihood, more variable/southwest/southeasterly for the southern part of England, potentially some thunderstorms in the far south. Temperatures around or slightly below average overall in the south is favoured but could see slightly warmer air clipping the east/southeast for the Easter Period, this is a very consistent possibility in my recent posts but precise timeframes being different, but with how unsettled it’s likely to be, it may not be of much benefit with a large amount of cloud possible. Gfs update this morning seems to show the high to our north slightly too east, further west is more likely. Overall it’s a similar outlook to the one I did about a week ago. After first week of April there maybe a slightly increased chance of lengthier drier conditions developing further for the UK although temperatures may not be particularly impressive from neither a cold/warm point of view, but sunshine totals may be somewhat above average. Have a good day.

Addicks Fan 1981 An unsettled/very unsettled end to the month evident on the second chart from noaa, with less unsettled few days in the south then changing to a cyclonic one, heights over Greenland. Air not particularly warm nor cold but northern hill snow risk as is entirely normal for the time of year and ties in with my thoughts since 8th March, though perhaps less wintry aspect than I thought may be the case, would give widespread cold and snow risks no more than 10-20% chance for easter period. Could be dealing with very slow moving fronts parked over UK, as stubborn heights may reside over central/Northern Europe for a time, then that weakening into first week of April with a possible drying trend for a time in the north and northwest, and continued unsettled south/east UK though with winds east/northeast certainly possible for a time.

Well there’s the briefest of north/northeasterlies if you ever see one.. The key change from the quoted post of mine above being the northeasterly that looked a possibility in the third week of March, wont take hold with blocking to our north proving weaker than expected at first, this also means northwestern areas wetter overall than southern areas. In the next few days after a continuation of wetter conditions widely, there is a stronger attempt from high pressure from our southwest to settle things down somewhat over southern UK especially, early next week, but staying more unsettled in the north at times though throughout, nothing exceptional and even here may see some drier days , these drier though not necessarily completely dry conditions may even persist in the south until the 21st or 22nd but like my previous post mentioned, any settled periods rather brief, no more than 3-5 days. Slightly colder and more widespread unsettled conditions return over most or all of the UK in the last week of March, with renewed risk of snow on northern hills atleast at first but may fall to some lower levels in the north by Easter, with an increased northerly and more especially northwesterly a decent likelihood, the risk of snow further south very low now but not to be discounted. Confidence rating of a more drier few days in the south with only occasional small amounts of rain for a few here? 95% Confidence rating that widespread unsettled and colder conditions return to all areas in the last week or so of March and most likely from our northwest rather than north with snow on hills in the north? 80% Confidence rating of a notably warmer than average spell moving north atleast once before end of March, has recently lowered to around 20-30%, there is a small chance of a brief southerly from a cut off low either over Spain/Portugal or just to the west of the UK/Europe around 23-25th and higher pressure over central and Northern Europe for a few days helping to draw very warm air north. In any case unsettled conditions would follow behind it and like I said before, it’s fleeting. Higher pressure is still liable to be close to over Greenland especially late in the month.

The couple of updates I made recently on those northeast winds after mid month over the UK looks “nailed” on.. lol ofcourse not, and no doubt will show a different theme by this afternoon (that won’t alter outlook thoughts in this post though) but the Gfs update this morning highlights the anticipated Greenland heights, very mild/warm air trying to establish from our south and colder conditions trying to establish from our northeast very well past mid month. The synoptics over the UK unlikely to look as extreme or as south shifted in terms of cold air and wintry precipitation as the Gfs is currently showing in reality and my updates recently have eliminated southern UK being in with a chance of wintry precipitation after thinking this could happen just after mid month when I did an update in the first couple days of March, but for northern UK, there is still a reasonable chance of colder (though not exceptionally cold) northeast winds trying to establish past mid month especially post 18th March to put a bit more detail on it, which is my 25th birthday. Due to the very cyclonic/unsettled nature of the weather over southern UK and across the “southern portion” of the Atlantic Ocean that looks to still feature throughout the second half of March and likelihood of high pressure nosing into western and Central Europe on occasion this is what will probably prevent colder than average conditions for the most part in central and especially southern UK, very wet at times still and that’s been highlighted well but with much more of the showery unsettled variety than the winter obviously due to increased convection so rainfall totals may actually vary somewhat from place to place here but could see some big showers developing, these wintry at times in the north, shower risk is though highest in the south with that ever strengthening sunlight especially in cooler upper air temperatures that look to be a feature behind southerly tracking lows that bring very mild air ahead of them either close by or over southern regions of the UK. Thought I’d add a confidence rating to my posts now so you can have an idea how confident a weather event or forecast per day may be to me atleast.. Confidence rating for the post mid month period attempting colder spell development in north UK: 50% so moderate confidence, most of the excess uncertainty coming from how much influence low pressure has in the north,high pressure more often than not largely close by here and that has been the consistent signal but there will be unsettled interludes in the north of the UK too with a continued risk of wintry showers along with dry drier days. Highs over/close to Greenland a 90% chance of that occurring at frequent intervals for the rest of the March. Confidence rating of 75-80% for southern regions seeing the wettest conditions overall and a bit milder with a consistent cyclonic pattern with low pressures moving mainly west to east being anticipated but also on occasion northwest to southeast and south to north through the rest of March bar fleeting high pressure systems that swiftly move across the country settling things down on occasion trying to form blocks elsewhere across our part of the northern hemisphere. Confidence rating of 60% that the synoptic pattern over west Europe will allow a temporary much warmer than average spell of temperatures into France and southern and southeastern England atleast once before the end of March, overall they look to be fleeting. The very end of March the Greenland heights may move and weaken slightly south and in the process bringing much colder upper air temperatures south across the whole of the country and into France, bringing the risk of a brief spell of below average temperatures with a bit of sleet/snow in places potentially including the south. Confidence rating for the very end of March potential colder than average blip nationwide, 30-40% with the main uncertainty being time frame given this is 3 weeks away, but to a lesser extent on exact trajectory of potential brief north/northeast air streams widely and whether they stay east of not around end of March. Have a lovely day

Morning guys, Subtle changes to the quote above here being the low out west more influential just before mid month (not talking about the lows in the next few days) but was highlighted as a possibility in my previous update, when high pressure tries to stay in charge of the UK just before mid month still but low to our west possibly interrupting an attempted developing anticyclonic pattern, spreading possible rain northeast across western and northwestern areas with snow on much higher ground possible. The Gfs seems to want to go with this above quote to a large degree in its latter frames, with the increasing chance of northeast winds into the north with snow showers and the risk of more persistent wintry precipitation once again being possible from advancing weather fronts moving northeast into northern areas from the south, with higher pressures tending to float around to our immediate north/northwest ie more Greenland as said previously, the wettest weather which will probably be all rain still looks to be for southern UK overall, with very mild air trying to establish further north into the UK aswell still likely, on the whole it does still look like often being drier in the north with some pleasant spring sunshine in the latter part of March but some colder nights could be a feature in any absence of winds from our south, potential is still there for southern and southeastern areas to tap into some warmer than average temperatures after mid month in an otherwise cyclonic wet spell, but there will be some drier days even here ofcourse, so yes looks wetter than average for March here but not as much as February. Very low chance <10-15% of widespread very cold northeast winds and wintry showers in south and snow persistent snow showers in north beyond mid month, this would be fairly akin to an update I made I think about a week ago for the same period highlighting that perhaps being more likely, ofcourse risk lowered now. The noaa chart below again shows the outlook anticipated well with heights likely to be prevalent near/over Greenland with any unsettled weather largely over southern UK and especially further south slightly still.

Ecmwf again today a good example of the above, before the Atlantic lows begin to make their move across particularly southern UK post mid month.