lorenzo
-
Posts
4,875 -
Joined
-
Last visited
-
Days Won
25
Content Type
Forums
Blogs
Gallery
Events
Learn About Weather and Meteorology
Community guides
Posts posted by lorenzo
-
-
Comet Phoenix......???
-
Gutted ISON didn't survive, would have been a great show during December, wonder how big a Sun Grazer has to be to survive an 800,000 km/h Perihelion??
-
-
Comet Ison is an easterly. Has the same nerve jangling anticipation !
-
Some wise advice there Catch.
ECM chart at 216 on the 00z has the pick of the cold air..
Still some way to go yet - good post from Nick F yesterday in the model thread re: the FI period for Northerlies. Question was raised as to whether we can look at FI for Northerlies to be at a longer time frame which I agree with, the models have caught onto these Northerly Blasts well this year, this will be the 3rd when verified.
Expect a wee bit of wobbling back and forth on the operational runs yet with respect to the main locale for the blast of cold. East West shifts, GEM whilst a bit like a crazy horse at longer range, did pick up the low at 96 hrs that gave the snow last week, so one to keep note of for the shorter term.
-
2
-
-
ECM looking great this morning, whilst this is at day 9 it has done well so far this season, had dialled into the last Northerly Blast from a similar range. This looks a little more complicated as a deeper and much colder low filters in.
Beats watching a mid latitude high !
Mon' the Snaw !!
-
4
-
-
Just spotted this gallery image on the homepage.
It is from an article written by John Hammond on the bbc pages. Well written article on how complex medium - Long range forecasting actually is.
-
7
-
-
Wave 1 and Wave 2 activity from the troposphere impacts the stratosphere. If strong enough / sustained enough, this activity can impact the polar vortex leading to either a Minor Warming or a SSW Sudden Stratospheric Warming. Wave 1 activity generally leads to 'displacement' events where the vortex is shifted off it's home, Wave 2 activity can carve up the vortex and lead to 'split' events.
Once the vortex is cooked there is an immediate tropospheric response, followed by a lagged tropospheric response where easterly winds burrow down through the stratosphere. These easterly anomalies bring the cold, however there are never any guarantees on how a displaced or split vortex will play out i.e where the core of the cold will spill to lower latitudes. Last winter is a strong example of how effective a SSW can be at changing the pattern as we really were stuck in a rut which flipped when the SSW kicked in.
This is why we look at what the wave activity is doing on the Stratosphere monitoring thread.
-
1
-
-
Very interesting update, some further information on the mysterious October Pattern Index (OPI) from a co-author Alessandro, this explains a little more around the science and method they are using to calculate the OPI.
Hello guys. First of all, forgive me the language .. I do not speak well English. My name is Alessandro and I am the co-author of the research OPI together with Riccardo. want to compliment you for the wonderful topic and specify only a concept about the difference between OPI and SAI .
OPI essentially measure the position and degree of intrusiveness of the planetary waves in the month of October by two parameters:1) degree of ellitticizzazione / elongation2) axis of polar vortexWhen we have a very tilted axis ( iceland -east Siberia / Aleutine ) and a pv stretched in October, like 2005/2006.a part of the rate of snow cover can not be measured as the snowfall occurring in the sea under the 60th parallel.In these cases the SAI approximates very well unless the AO .For this reason it is important to measure the position and the intrusiveness of the planetary waves rather than the snow which is nothing other than a consequence of the pattern of October.Soon we'll end the English translation and will submit to the competent authorities in the USA .Best regards ;Alessandro-
1
-
-
Not seen it Buried, was just going by information Matt had placed on Twitter, ECM32 is 'under the counter' weather chartage.
That last post is a belter, a man with a hat punching himself in the face. Genius.
I am Jacks raging vortex.
-
3
-
-
Would an economic dust bowl following an Independence winter be an appropriate weather related comment Lorenzo, cough, cough, blush!
Let me know if I have got this one wrong, certainly don't want to annoy the regulars, nor lose the banter on the thread. Just thought that SS thread may be better for more in depth discussion. Happy to be corrected, anyone else got any thoughts / ideas / suggestions..?
-
1
-
-
Another cold control run on the GEFS Ensemble, seems to be very reliable for the colder solutions so far this season. Still, nice to look at some very cold 850hPa temps here..
-
2
-
-
see when it comes to the strat I wonder if I am even thinking of it right i'll try and explain how I see it a little.
i'm using a crazy person as the trop and a sensible hat as the strat and a punch as wave activity.
the way I'm thinking of it is coming into autumn the trop is a crazy person who had just put on there sensible hat and the sensible hat works from top to bottom working the sensibleness down its hat trying to reach your head to take the craziness away but before the hat can take full affect if you were to receive a punch which crazys up your head more and in turn knocks the bottom part of the sensible hat out of kilter which the top of the hat has to try and overcome and sort out but if before the hat can get itself sorted out your always open to more craziness from further punches preventing the hat from connecting the sensibleness with your head and this continues till the hat takes over which eventually it will and the only way to get rid of the sensibleness all together is by burning the hat (SSW) but till the hat takes over fully and we have the need for burning it (SSW) we are open to seeing the craziness spill over to our part of the head due to the punches being felt and not just shrugged off.
hope that makes sense
The strat has got his hat on.. hip hip hip hooray... I get some of this Buried, the punches being Wave 1 and Wave 2 Activity on the vortex. As Catch said, a real classic !
Folks,
Would like to point you towards the excellent thread in the Serious Discussion forum started by Scottish Skier for all the political debate/discussion.
I am sure that reading through that thread in itself will leave you more informed than the paper published today !
Am not for moderating heavily so would love it if you could continue over there.
Thanks,
http://forum.netweather.tv/topic/69584-scottish-politics-2011-2016/
-
3
-
-
MJO starting to feature a little more as it has left the Circle of Doom ( origin).
GEFS into phase 2 and ECM into Phase 3
UKMO nearer the ECM side of things.
Couple of composites similar to previous, taking account of Westerly QBO and Neutral MEI. Also filtered for the GWO moving through lower AAM phases 1-4.
Low AAM
Matt just tweeted that EC32 goes for the anti-cyclonic outlook and these 'background' states would support this. Now to figure out the rest of the month !!
-
2
-
-
If only....All good things..
EC32 going for HP again.
-
5
-
-
good to see they temps as low as that and hopefully it comes of atleast we will start winter with a feel of it.
see the anomalies chart LS with the more blocked around Greenland and if you look at the op model run it is looking to try sink lows over us do u think if the anomalies chart is right with the more blocked greenland would this promote the heights to move into Greenland and the low heights to then slide into Europe.
or could this not happen with the PV where it is.
hard trying to explain bit tired.
Quote function has gone weird again !
Good to see your wrestling away with the questions Buried, anomaly charts can be deceptive, you can get predicted high latitude blocking across GEFS or ECM ens, only for nearer verification for the heights to not be as strong as forecast. The anomaly is based against the climate norm. so can get skewed, based upon what is the background state in the anomaly plot.
A good way to look at this presently is to follow the ENS against the operational on the Aleutian High, whilst it is ever present on the output, there is still inter run variability on how far it extends towards the pole.
Re: Dr Maue posts, Weatherbell had a lead of 10 days on the US snow storm and Arctic cold shot, I think the tweets are to back up this prediction. Joe B'Staardi has been video blogging about it for the last week or so. One of the occasions where the ECM has verified quite well from day 10, similarly it did well at day 10 for our 'Arctic Blast'.
-
2
-
-
Good link plotting the path of the comet as ssen by STEREO and LASCOs
-
1
-
-
Fizzled or not fizzled - that is the question.
This image from a few hours ago..
-
Gotta love the GFS 06z, if weather models were animals it really would be a daft auld dug.
It must know we are suffering from anti-cyclonic model blindness.
Throws in a trademark Uber Low
Anyone seen the 06z verify from 11.5 days out ??
Wouldn't trust it at 11.5 hrs
486dam air approaching the NWest of the Country. LOL !!
-
5
-
-
Yes - there is no science to my musing yesterday on this... but logic suggests that there must be some kind of early bounce back from a strat temp profile that is 4 weeks ahead of average. Either that or we are about to have the most dismal winter in years, dominated by a strong vortex throughout and next to nothing in terms of cold. Gulp...
I am trying to understand the precursors to a warming event, but nowhere near it yet. Lorenzo has posted some composites over the in the strat thread that show the historical positions or troughs and ridges when previous warmings happened, but they look like averages to me and I wonder too how great the data set is. Still - its a start.
Where is GP when you need him. He seemed able to pick out a torque event, or a change in the MJO at distance and make a call several weeks in advance. His loss to this forum is huge.
Wouldn't want you wondering CH, I think we can trust the paper, It's best in class current data http://www.atm.ox.ac.uk/user/mitchell/ Very strong academic pedigree and also collaborators looking at this list of publications
http://www.atm.ox.ac.uk/user/mitchell/dann_pubs.html
Dataset
Tropospheric precursors to warming events are something that is a backbone to studies on SSW, there are historic studies pre-dating the above paper and I am sure many to follow.
Yes I agree GP is a big miss, no doubt, but one thing about him not being around is that it forces the learning curve up and others can begin to work through where he left off. Safe to say that he was light years ahead of anyone else..
MJO forecast from CPC is updated on a Monday, so we will get an update on how they see it going later this afternoon / evening.
http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjo.shtml#discussion
-
1
-
-
Morning all! Temp got down to 0.6 last night so not quite up to cold winter standard yet. Calm and cloudy again today. Liking the look of that last chart Lorenzo! Be honest...d'you really think that'll ever come off?
Thanks for asking Misty, gives me a chance to dig this one out, one of my best Winter memories. Was at a football match with my Dad, and it got abandoned at half time, couldn't make it home, ended up staying at a friends as the roads were completely drifted out.
Not identical , but for our location shows the evolution is not impossible. At present, I would say unlikely in terms of December 2013, we can only hope !!
-
4
-
-
Mentioned ISON earlier, good thread and within it a post on viewing the comet here
-
2
-
-
- Popular Post
- Popular Post
RE ^
Looking through the Berlin plots this morning..
This at the 30hPa, heading towards 30m/s and a temp of -80 degrees, one compact vortexy looking vortex..
Some poleward EP Flux visible on the Strat plots, however the above gives you an idea of what it is up against.
SEND IN THE NUKES.
-
11
-
What you find BUS is that when the NWP has a less than impressive outlook, folks tend to visit the strat thread to see if there are any changes in the post that will alter things.
Re Troposphere vs Stratosphere. This excellent post from Chiono is a great visual description of what happens that addresses some of your thoughts from last evening.
http://forum.netweather.tv/topic/78161-stratosphere-temperature-watch-20132014/page-3#entry2809151
Beautiful clear morning, a nice crunch underfoot, hopefully more days like this to follow and we manage to get a view of ISON in the next couple of weeks should it survive Perihelion.
Looks nailded on Catch
Today, looking out for the latest CPC MJO update later on, will be interesting to see what this is due to be up to later in the month..
-
4
-
C/2012 S1 (ison) Could Be The Brightest Comet Ever Seen By Mankind
in Space, Science & nature
Posted · Edited by lorenzo
NASA tweeting that fate of ISON not yet established.
What ? Did it defy Physics pop down to the surface of the sun for a bit, before carrying on it's wonky trajectory.
Interesting C3 imagery coming out now.
C2 from similar timeframe