Blessed Weather

Many thanks both. Well I've just removed all cookies associated with Twitter and Netweather, plus cleared my cache, and still only seeing the text in tweets. I guess we're running out of options? It's the intermittent nature of the problem that's weird. Why do the pics/charts appear one minute and gone the next??

TWITTER PROBLEM The intermittent problem with posted tweets not displaying pics & tweets (just text) is still occurring. This morning I tried using MS Edge instead of my usual Firefox browser, but this made no difference. I have tried all the helpful suggestions made by @Summer Sun with the exception of clearing cookies (which I'm reluctant to do). The fact that this problem is occurring with another member @Bring Back1962-63 who uses two other browsers (Chrome and Internet Explorer) suggests to me that this either a Twitter or Netweather problem. Any comments please Support Team? Many thanks.

A very confident forecast from Weather Co Europe!! Note the highest precipitation is down the eastern side of the UK..... snowfall on easterly winds!

Thanks again SS. At the mo I'm seeing tweets OK (and it's the on/off nature of the problem that's puzzling). But next time they won't display I'll switch to MS Edge and see if they work with that browser.

Thanks SS. I've checked my Firefox settings and I've no extensions added, but do have 3 plug-ins (see screen grab). Seems remote, but do you think it's one of them? @Bring Back1962-63 David - do you use Firefox?

Hi Team. Sorry if this has already been raised, but there seems to be an issue with tweets. The pics/charts in tweets seem to disappear leaving only the text. Then later on the pics/charts re-appear again. Of course the lack of the supporting visuals can completely alter the value of a tweet, leaving readers puzzled. Is it a forum issue or maybe a browser issue? Many thanks.

This might be useful - a complete list of SSW's from 1958 to 2014 from a paper titled: A sudden stratospheric warming compendium by Dr Amy Butler et al, published in Feb 2017. The list is in Section 2.2. https://www.earth-syst-sci-data.net/9/63/2017/essd-9-63-2017.pdf

Hi Interitus. Thanks for your comments and pointers to other reading material. I was planning to read up and maybe come back with any comments or questions, but as usual with these scientific papers they refer out to other research, so I'm still in reading and digesting mode! I'm particularly interested in understanding the various precursors (and sequence) leading up to SSW events, so if I do have any further points to discuss I'll come back in due course if I may.

In his updated weekly blog Dr. Cohen has a go at predicting the impact of the imminent SPV split based on 'best fit' analogues and a recent study. I would say that the best analog was early January 1985 (central date of January 2) followed by early February 1991..... The temperature response across northern Eurasia was more consistent including Europe. For both January 1985 and February 1991 cold was widespread across much of Europe...... We showed in our recent BAMS study that the temperature response to significant PV disruptions similar to the one predicted this week is most robust across northern Eurasia. I include Figure 4 from the study in Figure i. Cold temperatures are widespread across northern Eurasia including Europe. Figure i: Finally in an earlier version of the BAMS study we had an alternate plot to Figure i where we present the NH temperature anomalies for the three weeks following a significant PV disruption broken out by week, which I present in Figure ii. Figure ii: Full blog (note: updates each week): https://www.aer.com/science-research/climate-weather/arctic-oscillation/

Here's an animation of the Polar Vortex split as forecast by the latest GEFS run (0z Mon 5th Feb). At the start of the run (5th Feb) the PV u-mean zonal wind at 10 hPa 60N is running at 45 m/s. This goes negative (reverses to easterly) on 12th Feb and by 14th Feb hits -21 m/s. Then a slow recovery so by the end of the run is -4 m/s. 5th - 20th Feb: As a graph: Upcoming deterministic runs awaited with anticipation as models get to grip with the impact down here on the ground! Charts courtesy of http://weatheriscool.com/ P.S. I notice recent tweets that have been posted in this thread, including mine, have lost any pictures/charts that were originally included and are now displayed as just text, completely losing the impact. Does anyone have any idea what is happening? Thanks.

A dusting of about 1cm here, just to the west of Ipswich. Temp +0.3C but dewpoint showing as -2C. The snow/sleet showers not making it far inland on the NE'ly flow.

Hi Interitus. As a learner I'm now left a little confused about whether MT does or doesn't impact the SPV. I have your post (above) but then @chionomaniac in the intro to the thread says: One warming event that can occur in the stratospheric winter is a Sudden Stratospheric Warming (SSW) ......... SSWs can be caused by large-scale planetary tropospheric (Rossby) waves being deflected up into the stratosphere and towards the North Pole, often after a strong mountain torque event. And this post (below) from The Weather Centre in 2013 says: As the animation shows, the last few days have seen a big jump in stratospheric temperatures in Eurasia as a result of a persistent rise in mountain torque values. Without going too in-depth, high values of mountain torque in certain regions of the world (in this case, East Asia) can lead to sudden stratospheric warming (SSW) events. http://theweathercentre.blogspot.co.uk/2013/10/stratospheric-warming-event-commences.html And then this research paper titled "The effects of mountains on the general circulation of the atmosphere" says: "In the model stratosphere, mountains increase the amplitude of stationary disturbances partly because they enhance the energy supply from model troposphere to the stratosphere". Extract: Full paper: https://www.gfdl.noaa.gov/bibliography/related_files/sm7402.pdf Which to me sounds like it's saying MT does impact the stratosphere? Which I therefore presume is a source of disturbance that can disrupt the SPV? Any further thoughts on this most welcome! Thank you.

This just isn't fair.... can we have some on the south coast of the UK please!!

Encouraging that the forecast imminent SPV split is expected to have a similar impact to the January 2009 event in terms of surface cold anomaly for Europe:

Lol. Dr. Butler clearly enjoying this ECM chart!!

Interesting tweet and associated report from the RAPID team monitoring the Atlantic Overturning Circulation. Report abstract and tweet: The North Atlantic Ocean is in a state of reduced overturning Abstract The Atlantic Meridional Overturning Circulation (AMOC) is responsible for a variable and climatically important northward transport of heat. Using data from an array of instruments that span the Atlantic at 26°N, we show that the AMOC has been in a state of reduced overturning since 2008 as compared to 2004-2008. This change of AMOC state is concurrent with other changes in the North Atlantic such as a northward shift and broadening of the Gulf Stream, and altered patterns of heat content and sea-surface temperature. These changes resemble the response to a declining AMOC predicted by coupled climate models. http://onlinelibrary.wiley.com/doi/10.1002/2017GL076350/full

Tweet from Dan Holley who works for Norwich based weather company Weatherquest and is also a weather presenter on the BBC Look East news.

Looking terrific up on Meall a'Bhuachaille above Aviemore this Friday morning, 2nd Feb!!

What an interesting week coming up! For now I'll hold myself back and just take a quick look at the first opportunity of this Region seeing some snowfall - which is overnight Sunday into Monday. The only 'high res' model that goes out far enough at the moment is Arpege and here's what it's showing. First of all - streamers coming into the east coast. Don't take the position too literally but merely indicative! With 2m temps slightly above freezing nearer the coast Arpege precipitation type showing it falling as rain: But if we look at the 850 temps (-6C) and dewpoints (0C to -1C) they are more supportive of snow, so I hope we could see a surprise or two, especially on any higher ground. Finally, for interest here's the current sea surface temps and anomaly in the North Sea. It's not far off the long-term average temp of 6C to 7C. But the temperature contrast with the 850 temps of -6C is enough to generate convective showers (streamers). So the Sunday into Monday set-up is rather marginal, but hopefully will give us a covering somewhere. Then further (better) opportunities Monday into Tuesday, but let's get nearer before looking at that in detail. Anyway, I've got everything crossed!

What a great post and a great read @Bring Back1962-63. Thank you. May I ask a question please. In your analysis of the MJO situation you say "This time it looks like the much stronger positive AAM tendency and the weaker Nina signal will allow the MJO to play a greater role." So..... with AAM finally heading into positive territory for the foreseeable (thanks to near-term +ve FT and - as @Tamara posted in the Mod thread - hopefully +ve MT "delivers something of an icing on the cake from mid month"..... and the ENSO signal is predicted to trend neutral as we move forward..... why are the models forecasting the MJO amplitude to nosedive when it reaches Phase 8?? With the background signals I would have expected amplitude to remain high?

It's looking very promising for you Reefseeker! Me thinks you're going to have a cold and snowy holiday so get the thick fleeces ready to pack!! And good to see colder temps and snow arriving in Filzmoos tomorrow. Snow-forecast.com (who use GFS data) is forecasting 50cms + at village level and 65cms + at mid-mountain over the next 5 days, so the village should look very pretty when you arrive on the 7th Feb. 5 day forecast for village at 1,057m Obviously subject to change at this range, but here's the current Netweather Alps forecast temps for your arrival on Wed 7th. I've shown approx where Filzmoos is on the first chart. Lovely and cold! 12.00 21.00 snow-forecast.com link: http://www.snow-forecast.com/resorts/Filzmoos/6day/bot

GEFS ensemble mean going for a zonal wind reversal around 14th/15th Feb. Presumably this was today's (Wed 31st Jan) 06z run.