Uncle_Barty
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Posts posted by Uncle_Barty
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The 2000z reading last night was 136.6 = highest since mid June 2015.
This cycle properly ramping up now.
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1700 solar flux reading 121.6, highest of the cycle so far, though this may be flare-enhanced.
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X1.0 flare around 1540z today. Looks very likely to be earth-directed.
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On 20/09/2021 at 18:31, mb018538 said:
Yep, and the 12z runs carry on in this vein. A very different end to the week than we were expecting a day or two ago, and for many it’s fine and quite warm right through to Saturday now. Up to 23c on every day now forecast.
My September mean remains at 18.0c (17.3 for August). With this outlook, I just wonder how much that average will come down.
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Favourites
Mid-May to Mid-August. High summer, or the promise of.
April. Things starting to grow, days properly lengthening.
Late Feb/Early March. That feeling of knowing the worst of the winter darkness is behind us.
Worst.
November. Clocks have gone back, it's getting dark and dank, and you know you still have the whole of bloody winter ahead of you. Hate it hate it hate it.
December/Jan. Winter. Enough said. Just the feeling of wanting to get through to spring without too much weather disruption, footy fixtures getting buggered about with and so on. Though if a nice fat Bartlett takes up residence, things arn't so bad. 1988/9 winter was quite bearable in that regard
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3 hours ago, Tamara said:
There is nothing to change this thinking. Not even the bizarre 'law of sod' methodology which overtakes this thread.
So, to the diagnostic.The GWO, subject to 2 day lag, has been orbiting to low angular momentum phases, circa Phase 2, following the downward momentum drift that began in late July - not coincidentally the time that the fine, very warm spell broke down in the UK and other parts of NW Europe.
The 40 day phase plot clearly depicts the ascendency of momentum during the first half to two thirds of July, and the steady improvement from the unsettled start to the month to that late month breakdown.
Despite this, there remains the opportunity for a third fine summer spell c/o ridging into the last phase of this month for NW Europe to see official summer out in a way that it began. As suggested in the previous post, its a case to what extent the high frequency tropical wave can, temporarily, diffuse the underlying Nina-esque standing wave which continues to develop as the Pacific maintains upwelling effects of cooler water to the surface.
Is this a reference to the MJO moving through Phase 3 into Phase 4? Or perhaps I have the wrong end of the stick, as this still suggests a lack of convection over the E Pacific (cold SST anomaly/Nina) confirming the pattern rather than temporarily diffusing it?
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On 11/08/2021 at 17:46, Singularity said:
Worth noting that we now have a big negative mountain torque underway, following a big positive one.
Whats the difference between a negative and a positive nountain torque event?
I'd just assumed mountain torque events in general tended to contribute to a lower AAM.....
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6 hours ago, Tamara said:
Olá, tudo bem
This extract from previous post still seems good for continuity purposes. That intra-seasonal signal discussed in the post looks to provide another phase of eastward temporary migration of the Atlantic ridging and a rinse and repeat of the mid to late July pattern as angular momentum tendency responds to eastward propagation of tropical convection through the Maritime continent in the last third of August
The GWO holding around weak Phase 8 to no discernible signal (Phase 0) in the short/medium term which retains greater Atlantic ridging element.....
....but with a westerly wind burst beginning across the Indian Ocean and propagating towards the Maritime continent this should start to correspondingly adjust the rossby wave pattern eastwards as active tropical convection and thunderstorm activity replaces suppression in this region - and then on into the Western Pacific.
The net product of this likely to orbit the GWO back to Phase 4 (greater downstream ridging) before the low frequency walker cell reclaims ascendancy and Pacific re-amplification re-sets the wavelength back to the downstream ridging in the Atlantic.
However, before all that, a good chance for some fine, very warm later summer weather for NW Europe during the last third of August. In the immediate term, heat is building down here across southern Europe. 30C locally today and tomorrow (around the August seasonal daily maximum average) rising through the latter part of the week with 36/37C likely by Saturday - edging back to 32/33C by Monday. Further inland still ,towards and over the Spanish border and through the Portuguese Alentejo and Algarve regions, values of 40C or more look very likely
ECMWF 14-day ensemble weather forecast for Fazendas de Almeirim | Meteologix.com
Screenshot
Thank you Tamara.
Quick Q - where does one find the GWO charts? Looks like NOAA have stopped publishing them.
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On 04/08/2021 at 17:15, Tamara said:
The very few cloudier days get a discussion going down here!
The last rain that fell was about five or six weeks back, and with a few thundery showers before that earlier in June, so close enough to the theme of a Mediterranean summer even though there has not been any true sustained heatwaves of 35 to 40C (and upwards) beyond a couple of brief spells in July.
Its no guesswork involved that the two periods, so far, of this summer, that have seen a departure from the changeable cooler and sometimes very wet pattern that UK and other parts of NW and central europe have seen have coincided with momentum shifts upwards between the tropics and extra tropics. The first being in the opening ten days to fortnight of June and more recently the mid to latter part of July. The downturn from mid June to the first part of July, and the latest one on-going, being a result of the high frequency tropical cycle returning to mirroring an underlying increasingly Nina-esque standing wave once again and associated generally rather lower than average atmospheric angular momentum tendency.
The Global Wind Oscillation phase plot, (a depiction of wind-flow inertia within the atmospheric circulation which gives a useful diagnostic guide to jet stream behaviour) and also the angular momentum anomalies themselves (that the GWO mirrors in its orbits) both illustrate those two relatively short upward cycles within otherwise supressed tendency. Its a deliberately simplified illustration (with rather pedestrian hand-work) but it does provide a mirror for correlation purposes.
In synoptic terms (for summer wavelengths) this ebb and flow pattern revolves around the movements of a stronger than average Azores high sub tropical ridge (the one that gives the stable sunny and very warm/hot conditions to southern europe). However, with tendencies for this to retrogress its influence across more northern parts of europe due to upstream wind-flow inertia decelerating c/o rossby waves amplification occurring across the Pacific when tropical connection suppression takes hold across this section of the tropics and sub tropics.
The net effect of recurring Pacific amplification is to keep re-setting the downstream pattern to a trough/ridge/trough pattern - with the final ridge /trough arrangement being across the west/central atlantic and north western european sectors respectively. As suppression briefly wanes across the pacific, c/o (1) eastward passage of the high frequency tropical cycle increasing wind-flow across the Pacific and sending the (2) amplifying rossby wavelength downstream, then the trough over UK/NW and central europe is replaced by ridging for the temporary period that this interference with the background base state exists.
Its hard to see a break to this pattern cycle rut at present, and with signs that a La Nina-esque hold on the wider hemispheric pattern may strengthen again heading into autumn. This makes it likely that Atlantic ridging will continue to dominate proceedings overall, though as per the previous post, its worth watching out to see how tropical storm activity intervenes if, following any recurving tropical storm (from within the Equatorial Atlantic) another intra-seasonal kelvin wave crosses the tropics and a further temporary rise in angular momentum occurs. This maybe more likely late this month and perhaps into September. Other than this, any hotter spells and more southerly winds (for UK/NW Europe) seem harder to come by and restricted to breakaway ridging transferring eastward ahead of main troughs and associated advection of brief plumes. Though again, this sequence could be further amplified or augmented if any tropical activity gets caught up in such a sequence.
Lots more lovely sunshine and customary warmth to come down here ( nothing likely to top up the water bore-hole for some time yet), but a case of making the most of the drier, warmer and more settled spells when they come for the majority interest of the forum in the UK
Thank you once again, Tamara.
Just to aid my understanding here.. from your post above:
(1) Are you referring to the MJO here?
(2) This is a reference to the waving jet-stream?
Is a Kelvin wave (atmosphere) connected to the MJO, or are they different processes?
I am assuming that the La Nina pattern is driving the default Atlantic ridge/ NW Euro trough, with a reasonably strong MJO event (and/or other factors) temporarily disturbing that pattern? I also read in past years that there may be, at times, a "decoupling" of the atmosphere from the ENSO state.. what drives that?
Thanks
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Matt Hugo pouring cold water on any suggestions of a better outlook on Twitter.
Tropics MJO/La Nina pointing towards a "disctintly average - poor" August.
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47 minutes ago, davehsug said:
The problem with means is that when the operational are so bad, the mean will almost always look better. I've spent many years of seeing people post "not to worry, the mean is much better". Means are by definition an average, and with so many ensembles, they will tend to produce average weather charts.
exactly this. Better to look at the clusters. I usually pretty much ignore the mean.
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Of course, what could well happen is that the Scandi high is corrected east with time, and if the Azores ridge amplifies into the Atlantic, we'll be left with the limpet trough over us.
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Matt Hugo on Twitter trying to pour cold water on those hoping for much of an improvement going forward...
"Caution required over this signal for high pressure to build into the British Isles from the W through late June...We are still about to see a trend towards a -ve AAM regime. A more changeable/unsettled pattern still remains more likely towards months end/early July..."
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12 minutes ago, B87 said:
Was 1987 not one of the worst summers of the 1980s? The stats for London at least show it as a very cool, cloudy and quite wet summer.
It was quite mixed here. Very poor June, decent first half of July, then the rest of the summer was quite mixed. Got a lot worse the further north you went, IIRC
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1 hour ago, DiagonalRedLine said:
Of the 00Z runs, the ECMWF continues to show a build of heights and High Pressure over us from next weekend onwards (168+ hours):
Ideally, the High could still do being a bit further East (room for that to happen). Is still a welcome change. North-Western and Western areas would likely see the best of the sunniest spells in general.
Do hope the ECMWF is on to something, though, because, weather-wise, am getting bored of this November
last November: Mean max 12.9. mean min 8.1 Mean 10.5 Rain: 58mm
This May to date: mean max 13.9, ,ean min 7.7, mean 10.6. Rain: 64mm
Not too dissimilar with one "freak" day of 18c this week helping the mean max.
At least there looks to be an upward trend in the models.. perhaps the background signals hinted at by Tamara a few days ago are starting to have an effect.
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In 25 years of keeping records, I have NEVER failed to reach 21c / 70f before the end of May.
That record definitely under threat this year.
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13 hours ago, Snipper said:
Been wondering about this thread. Read for a while from the start but for the uninitiated the football score reporting of many of the posts with no comment or observation makes it rather obscure concerning what is going on. Is it possible for someone to give an updated review concerning what is going on and potential both good and bad in the future.
This thread http://skywavesdx.org/viewtopic.php?f=53&t=7925 will give some information. Wikipedia and other sources can also give more info.
As for the effect on the weather - some are of the opinion that low solar activity = more blocked / colder winters. I'm not convinced, personally.
If anyone has any more questions, I'm happy to answer them.
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Updated the Solar Cycle Progress thread, including Jan and Feb data, here
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50 minutes ago, James Maidstone said:
I think there is other stuff coming into play here such as:
- the underlying warmth of the ground from last week which is still not that cold
- solar heating in the day from when the clouds clear in the afternoon. I think even under colder uppers such as minus 20 you can still get partial melting in the day due to solar activity. Someone please correct me if I am wrong?
We had a dusting today. Where I work, the dusting just disappeared yet no sign of melting.
Google "sublimation"......
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42 minutes ago, MattStoke said:
-7’C 850hpa temperatures or lower on the ECM in a flow from the continent. More than cold enough for snow. I often see snow in a north westerly flow with 850hpa temperatures of -2’C. I know I have a little bit altitude and I’m not in the far south but it’s not like I’m on top of a Scottish mountain. If the latter can bring me snow, the former sure can bring snow to those lower down and further south!
I've had rain down here on several occasions with uppers of -8.
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3 minutes ago, Alexis said:
ECMWF at 144h - I'm calling that a victory for the GFS and UKMO and a defeat for the best model.
It is foolish to call a victory for one model over another at 6 days out in this setup. FI probably at 72h at the moment.
Wait till it verifies.......
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11 minutes ago, Tim Bland said:
Did you move to Bournemouth for the Snow? . Jokes aside there is a chance of some for you this weekend whichever model you look at
I don't actually enjoy cold weather at all. Give me a nice fat Bartlett and a blowtorch SW'ly all winter long so far as I'm concerned. A big freeze always interesting from a weather POV of course.
As for snow this weekend... looks very likely to be the wrong side of marginal down here, except well inland.
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Indeed... unless the heights around Iberia shift, it's very difficult indeed to get cold air over the southern part of the UK at the very least.
Not seen a flake of snow yet this winter in these parts.., not expecting that to change any time soon.
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1 minute ago, Stu_London said:
Lots of uppers angst again today.
There are reasons why -8C would be more likely deliver this time, whereas it didn't last time (although uppers in the south east were generally a degree or so below -8C in the last spell in any event)
However until the overall pattern is decided, it isn't really worth sweating over. I think it could be as late as Friday or Saturday until some sort of model consistency is achieved for next week.
If we get a low stagnating over us that starts off on the cold side, it will likely only get colder over time at this time of year.
I don't think snow chances can be written off for anyone, though in my locale it will always be marginal at best.. yet to see a flake of snow this winter.
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Solar and Aurora Activity Chat
in Space, Science & nature
Posted
Not a chance!
1800 reading today: 142.4