Jump to content

All Activity

This stream auto-updates     

  1. Past hour
  2. More snow to hit Sweden after temperatures drop to new record cold WWW.THELOCAL.SE The lowest temperature of the winter season was recorded early on Thursday and more harsh winter weather is on its way, national...
  3. Must be getting fairly close to a below average month? (if anyone knows the stats so far)? Don't recall very much if any mild weather during November at all (and don't look like warming up rest of the week either)
  4. 6.9c to the 12th 0.9c below the 61 to 90 average 1.6c below the 81 to 10 average __________________________________ Current high this month 10.6c to the 1st Current low this month 6.9c to the 12th
  5. The norm for early SSW events is actually for the stratospheric vortex to be strong in late winter (though small sample) so it may be that it simply expects Jan-Feb to revert.
  6. Met office yellow warning for ice NE and E Scotland Wednesday and Thursday. Yellow warnings for rain for parts of England Wednesday to Friday.
  7. Here’s the GEFS mean at 144, now I know what happens later on with that dartboard low scuppering things, but it won’t take much of a change for things to quickly make a turn for the better for coldies.
  8. That's regarding GloSea5. I guess it can't take an SSW in to account because the data has already been assimilated?
  9. Thanks for your reply and comments above..... It is undoubtedly true that the Pacific side of the Arctic has 'struggled' for the last few years. However, I believe, all is not lost. Beaufort as you have shown from the Masie time chart went thru a very bad period about 2-3 weeks ago. It is now catching up with its normal rates of 'icing' . Chukchi is a disaster this year - no way of avoiding that … (as you show in your chart ) However, remember that the longer it stays ice free then the more it is going to cool down. (via more heat loss). However the one absolute factor which 'cheers' me this year is that the Bering Straits, (remember that is the entry of the Pacific), is freezing more quickly. (see graph below). That does not tie in with the 'Pacification' theory. In addition to the quick freeze in the 'western' Atlantic front, we now have the extreme East showing signs of change at the same tiime. Is it temporary? Time will tell. But if it stays around then it will mean a quicker refreeze into the Pacific, via the SOO. So at this moment in time, the situation is not clear. It is too early to start to claim disaster. We have not seen the Atlantic ice front perform this way for about 10 years. (maybe more). Is what is occurring in the east (Chukchi, and mainly the last 2-5 years) temporary? Is it caused mainly by the entry of warmer waters from the Pacific into Bering? Or is it the persistent high temperature anomaly being shown for Chukchi in particular? If so, has it anything to do with the high levels of stratospheric ozone over exactly the area under examination? I feel we need to wait and see how this develops. As Fred (aka BFTP) has suggested it could be that oceanic factors are beginning to change, and that they will play a greater and greater part in what develops over the next few years. Is the 'low solar' impacting this year? However - no one knows - yet. MIA
  10. Nice frost this morning here in bright sunshine. Temps rising now up to -0.3C. Nice pic here of Ben a Ghlo taken from Errichel looking NE over the fog inversion in the upper Tay valley.
  11. Glosea is a high top model & will be able to factor in the SSWs into the seasonal forecast however its only in the last week or so this has become more visible in the models - based on that the next seasonal run of the models in particular Met office & ECMWF will be very interesting...
  12. Aplogises Yarmy i didnt read the paper i saw a few words that consisted of more than two syllables and left it i shall take a better look later. On a further note if this is the case why do people hold so much weight in this type of seasonal forecast
  13. It can't. At least if we assume it has roughly the same limits on predictability as the ECMWF extended range model in the paper above. The Feb 18 SSW wasn't picked up by any of the extended models at a range of just 12 days, according to the paper by Lee et al. posted further back in the thread.
  14. Thanks for that. A quick question regarding the Strat does the position of the warming make any difference to the outcome or are there other variables at play? For example the above shows the warming and a near split above Alaska/Canada Would the subsequent vorticies then behave different if the warming were above Greenland for example?.
  15. I presume the Glossea forecast for the following three months takes a warming Strat into consideration?. If so ( and i know it may be difficult to gleen from a mean) but why does it scream a raging + nao and mild temps?. is it just that it does not see a SSW coming to fruition
  16. For viewers in this thread who don't always post heres a few numbers & signposts as we head towards December ( say from 20th Nov onwards ) These are for Stratospheric Zonal wind @10HPA Current Speed 41.8 M/S which is classed as a strong vortex. ( Old date record for today 2015 - 40.2 M/S Average December Start point - 30 M/S Average Peak zonal wind ~ Ironically ~ Christmas day 38 M/S which is why statistically Christmas day is mild. Lowest End of November > (20th Nov ) zonal Wind value 7 M/S 2009 - December AO was -3.4 Earliest Decemeber SSW was 1981 & the AO was -1.26. Current lowest forecast from last 4 GFS operational runs continue to creep down ( very consistent ) 12.5M/S but notice the trend. The lowest 00Z ENS value is 4.19 M/S however todays havent been updated yet- Glosea yesterday was modelling the same transition yesterday with a powerful warming however perhaps on the interim between late November shows a signal for lower polar heights - So based on that we see the AO peak negative then neutral / pos until the warming & deceleration downwells- Im not 100% convinced on that but we will see. So benchmark the date 27th November as time when the deceleration moves to its final phase....
  17. Today
  18. It seems my last reply got lost. We've recorded a 100 mm plus 22 times since 1955 in November. Over the years this is the 2nd time we will have recorded hundred millimetre recurring 6 times and that's from 1955 but it's quite common to record several months having a hundred or more millimetres. There is a chance that we will record half of the year's normal rainfall in the autumn alone which is amazing. There's also a small chance that we will record the wettest year ever which is 1217 mm recorded in 2012. It's is still uncertain how much rain the region will get on Thursday into Friday either way it looks pretty certain we will make a new record for the wettest autumn ever in Sheffield.
  19. JFF after D12 we see a Pacific wave develop and this enables the Euro High to build north with WAA to establish less of a wedge block to a more Rossby wave synoptic... ...driving some of that cold south into E.Europe. On this occasion the Pacific heights are transitory, but will gift a wedge of heights into the Arctic fields, that may mix it up a bit? All great for the long game no doubt.
  1. Load more activity
×
×
  • Create New...