I can! Oh wait...Someone needs to make a thread for Tuesday/Wednesday. You know it will not be me.
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I can! Oh wait...Someone needs to make a thread for Tuesday/Wednesday. You know it will not be me.
That system has trended toward being sheared out. However, teleconnections, MJO progression, and the overall pattern as a whole makes it look like the next few weeks may very well be fairly active.I see that there is now a chance of thunderstorms next Saturday 4/2 for north Alabama. Is this the system that everyone is concerned with?
I understand that I will be criticised for saying this, but this has been happening abnormally frequently, at least this winter, under an otherwise conducive -PDO/-ENSO setup. With an exception or two, have been seeing a lot of high-amplitude, meridional, sheared-out systems this winter instead of low-amplitude, latitudinal, consolidated systems. Normally, a near-record-breaking -PDO combined with a solid Niña would be producing something closer to what was observed during the winters of 1999, 2008, etc. I think that global warming is altering the background state due to expanding Hadley cells and warming seas (Indian-Pacific) and is thus leading to more high-latitude blocking and fewer synoptic-scale setups that are conducive to widespread outbreaks with multiple cyclic storms over a broad area vs. an isolated significant tornado or two. The December 2021 outbreak, like Easter 2020, was an exception to the otherwise pronounced downtrend in large-scale events since 2012, regardless of ENSO and PDO.That system has trended toward being sheared out. However, teleconnections, MJO progression, and the overall pattern as a whole makes it look like the next few weeks may very well be fairly active.
Late 1955-early 1956, Late 1988-early 1989 Both negative PDO combined with soild Nina didn't produce the high end outbreak you definite. This negative PDO/Nina period already had 12/10 outbreak which was historic and unprecedented for winter season.I understand that I will be criticised for saying this, but this has been happening abnormally frequently, at least this winter, under an otherwise conducive -PDO/-ENSO setup. With an exception or two, have been seeing a lot of high-amplitude, meridional, sheared-out systems this winter instead of low-amplitude, latitudinal, consolidated systems. Normally, a near-record-breaking -PDO combined with a solid Niña would be producing something closer to what was observed during the winters of 1999, 2008, etc. I think that global warming is altering the background state due to expanding Hadley cells and warming seas (Indian-Pacific) and is thus leading to more high-latitude blocking and fewer synoptic-scale setups that are conducive to widespread outbreaks with multiple cyclic storms over a broad area vs. an isolated significant tornado or two. The December 2021 outbreak, like Easter 2020, was an exception to the otherwise pronounced downtrend in large-scale events since 2012, regardless of ENSO and PDO.
The winter of 1955–6 actually did feature one or more significant outbreaks on 15–16 Nov ‘55 (eight F2+ tornadoes, including three F3s, per Grazulis [1993], p. 991) and 24–25 Feb ‘56 (14 F2+ tornadoes, including two F4s, per Grazulis [‘93], p. 992). Springtime ‘56 also began with the major outbreak of 2–3 Apr (33 F2+ tornadoes, including nine or more violent tornadoes, depending on sources ranging from the NWS to EJSSM and Grazulis [‘93]).Late 1955-early 1956, Late 1988-early 1989 Both negative PDO combined with soild Nina didn't produce the high end outbreak you definite. This negative PDO/Nina period already had 12/10 outbreak which was historic and unprecedented for winter season.
The conclusion you made was possible theoretically, but I don't believe the whole evolution of the climate system is as simple as you said.
All these high TNI/negative PDO things was more about possiblity. I don't think there was a certain setup ought to produce historic outbreaks.
That system has trended toward being sheared out. However, teleconnections, MJO progression, and the overall pattern as a whole makes it look like the next few weeks may very well be fairly active.
I actually think that timing may be a bit too fast, and it looks too fast when looking at the ensemble data. The period from the 3rd to probably the 6th or 7th is going to be about the -NAO coming to the end, but it's going to take a few days to do it. The big start of April troughing in the east shifts northeastward, and that dislodges the ridging over Greenland. I wouldn't rule out a threat (maybe even a significant one) around the 7th-8th or so right after the -NAO weakens. From there on out, all ensemble data is screamingly consistent (run to run and ensemble family to ensemble family) that the whole pattern lays down and goes low amplitude, the classic low amplitude pattern that you would expect during a strong -PDO, a firmly established La Nina and a high-end +TNI spike. This is honestly acting much more like a first-year La Nina than a second-year, which isn't too much of a surprise given that last year acted more like a Nino than a Nina with the subtropical interference, the consistent -SOI, etc. That concerns me because when this does go low amplitude, we aren't just going to strongly ridge out and all this shift northwest of Dixie Alley.Looks like that system got pushed back to around 4/4-4/5 on the GFS. Then there are hints of another one possibly around the 10th. Also some hints that one or both of these troughs may not be as highly amped with a squashed E-W wavelength.
In other words, Deep South and OH Valley are stuck with high-end severe risk like it was back in last half of April 2011?I actually think that timing may be a bit too fast, and it looks too fast when looking at the ensemble data. The period from the 3rd to probably the 6th or 7th is going to be about the -NAO coming to the end, but it's going to take a few days to do it. The big start of April troughing in the east shifts northeastward, and that dislodges the ridging over Greenland. I wouldn't rule out a threat (maybe even a significant one) around the 7th-8th or so right after the -NAO weakens. From there on out, all ensemble data is screamingly consistent (run to run and ensemble family to ensemble family) that the whole pattern lays down and goes low amplitude, the classic low amplitude pattern that you would expect during a strong -PDO, a firmly established La Nina and a high-end +TNI spike. This is honestly acting much more like a first-year La Nina than a second-year, which isn't too much of a surprise given that last year acted more like a Nino than a Nina with the subtropical interference, the consistent -SOI, etc. That concerns me because when this does go low amplitude, we aren't just going to strongly ridge out and all this shift northwest of Dixie Alley.
Not in the same universe as what I'm saying. Welcome to the forum, but please sit back and lay off the mass death and destruction. Not every severe weather pattern will be that.In other words, Deep South and OH Valley are stuck with high-end severe risk like it was back in last half of April 2011?
Right. You can take 4/27/11 and cut it into just a third, and you'd still end up with a day that has as many EF4+ tornadoes as days like Super Tuesday 2008, May 4 2003, etc. You can take just a small fraction of 4/27/11 and have a fully verified SPC High Risk tornado outbreak event.4/27/11 was such an extreme outlier, that there is plenty of room for outbreaks that are well short of that threshold yet still plenty impactful and dangerous in their own right. We just had a good example of one in December.
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Just hope that analog doesn't extend into the following month (May 2006 flipped to eastern troughing and was horrible for chasing).What amazing , as bad as April 27. 2011 was , the system think it was April 6. 2006 actually had a higher ceiling , with 60 percent tornado probs , almost unheard of course it didn’t quiet pan out that way but still significant everything popped up that day went to rotation quick , with plenty spacing for long tracking violent tornadoes. And 2006 April keeps popping up top analog for this coming April . Interesting
Where and from whom?What amazing , as bad as April 27. 2011 was , the system think it was April 6. 2006 actually had a higher ceiling , with 60 percent tornado probs , almost unheard of course it didn’t quiet pan out that way but still significant everything popped up that day went to rotation quick , with plenty spacing for long tracking violent tornadoes. And 2006 April keeps popping up top analog for this coming April . Interesting
What was thinking be honest , read it over on couple other weather forums be honest…Where and from whom?
April 2006 was ENSO neutral after coming out of a brief, weak La Nina that had previously registered as neutral peak in previous climo sets, that was sandwiched between two El Ninos... with a firmly negative TNI and a neutral to positive PDO in place. From December 2005 to May 2006, the lowest the PDO got in that whole period was -0.04. Not a good match to what we have in place right now, especially in terms of the things that drive a severe weather pattern. Spring 2006 was much less favorable in a classically speaking sense than what this is.