cbmclean

Even without the ignore button, I just skim over his posts and also all the posts arguing with him, except when someone actually presents hard data which I find interesting. Speaking of which I downloaded the hard data for RDU from the NOAA and have started to slice and dice various interesting statistics. So far I have seen that December was "only" our 12th warmest, but it was tied for 6th for least number of days with min<32. Has anyone seen the numbers for Dec and Jan for IAD and DCA in terms of Tavg?

CPC page gives this definition. I am trying to make heads or tails of it. " The daily AO index is constructed by projecting the daily (00Z) 1000mb height anomalies poleward of 20°N onto the loading pattern of the AO. " So I understand the concept of geopotential height anomaly, although I am not used to see it at 1000 MB. What does it mean to "project it on the loading pattern".

Thanks! I find this stuff really interesting.

I think the +++++AO and the strong PV are different names for the same phenomenon. In other words, the AO index is a measure of the strength of the PV. Please someone chime in if I am misinformed.

Anyone able to give a quick explanation of what a "wave breaking" is? Seen it mentioned several times this winter.

Well that is a known Euro bias, or at least it was in the past. I am still just going under the policy of assuming the actual outcome will be the worst of all modeled outcomes.

At this point I am ok with that. I know its a different story for you guys maybe getting some March love, but down here it's pretty much over for us. Just give me some cold to keep the bugs at bay for a little while. I just hate hate hate those nights right before FROPA where its like 65 and humid at midnight.

If he is referring to the chart that Bobchill posted, it is the 1981-2010 period. This year has just started to sneak into the bottom of the interdecile range.

Its more east-central. My climatology is nowhere near you guys. I hang out here because the posters are the most knowledgeable and the large scale pattern drivers are mostly the same for me as for you. NC is fairly diverse for climate at its latitude. The SE quadrant (Wilmington and environs) is darn near tropical. The NW piedmont is much more continental (relatively speaking of course) and the high mountains actually get a good bit of snow.

The "ground truth" of what? Does he mean that more frequent good years are holding up the mean while the median is steadily declining? If so, he's probably right. Should be easy to parse the numbers if one has the data.

Sigh

My area has recorded its earliest leaf out in the 39 year history of the metric. It is currently 71 °F at my house.

I remember PSU saying the seasonal models were predicting a mostly +AO state and him being puzzed why. Whatever they saw, they were right.

What does he mean that he holds snowfall anomaly "in disdain".

Oh we will, this is just a thought experiment to wile away the time.

Depressing yet fascinating. I wish I was an eccentric billionaire who could found an institute devoted solely to studying teleconnections seasonal forcing. As an aside, I also noticed from the graph the strong negative correlation between to anomalies in in the Davis Strait/Baffin Islan/Labrador/SW Greenland area. That is where the PV has been parked much of this winter and I seem to remember showmethesnow mentions this area in a response he posted recently. So apparently when the PV strengthens it tends to get drawn to this area like a moth to flame? Do know why this is? Why isn't it equally like to set up shop over Ellesmere Island or Barrow or Novaya Zemlya?

I noticed an interesting graphic on the Arctic Oscillation page for Wikipedia. This is a counterpart to the graphic that Don S. posted for extreme AO events, but generalized for all AO. So I notice that basically the only midlatitude land which isn't on fire is the western CONUS, just like we have seen this season. But I also notice the mean warm anomaly north of Hawaii. So seems like more evidence that the Pacific Doom Blob of January wasn't just coincidental with the continuing pain that is the AO this year. The PDB is perhaps just a manifestation of the +++++++++++++++AO. And I am probably not telling anybody anything they didn't already know, but it struck me.

Only need 20 more straight years of this, and we might have the Arctic sea ice back in a reasonable shape. Actually, this is an interesting hypothetical discussion. There is a rather strident guy over at WattsUpWithThat (don't throw tomatoes, I just go there for the graphs, honest) who is convinced that the entire institution of climatology is full of poo and that AGW is not going to be a big issue because it will be severely moderated by negative feedback mechanisms. One of the negative feedback mechanisms that he has touted is increased cloud cover due to convection in the SW Pacific. So for fun's sake let's just assume the following hypothetical: that he is on to something and the increased MJO forcing in the maritime continent/crap zones that we love so much is actually impacting the AO to become more positive. So let's assume that our recent predilection to go on season-long grand tours of zones 4 -5- 6 is the new base state which will cause us 20 straight years of snowless misery, give or take the occasional fluke. BUT let's also assume that it will cause a continual +++AO which will keep the cold air locked up in the Arctic and will thus help the Arctic sea ice to significantly recover. So my hypothetical question is: will you guys accept the trade-off. Would 20 years of this kind of fail be worth it to get back to the halcyon days of yore with a cool base state?

I was under the impression that the late December fail was a different beast: the AK vortex Pac Puke. AO was actually negative from roughly Dec 15th - 25th or so, but was trumped by the mild Pacific air.

OK everybody how does this year rank among the great dumpster fires of the last several decades? Hating this more/less than 2001-2002, 2011 - 2012 etc?

Something is puzzling me about how extreme +AO evens. Earlier today frd shared a post from Don S. about 500 HP/temp anomalies of extreme +AO events. The pic below is taken from Don S.'s post. So as they teach us in beginner weenie school +AO means PV/polar jet is stronger than normal so tends to keep low heights bottled and cold air bottled up in the high latitudes, with warm air in the middle latitutes. And you can see that to be the case in Don S.' plots, a ring of ridging/warmth in the midlatitudes: the eastern CONUS, Europe, China. BUT there for some reason there is a big trough/cold anomaly in teh western CONUS. Anyone have any idea what that is all about?

I'm honestly interested in the AO watch, following the once-in-a-lifetime chance to see it go to +23. I am rooting for the heights in the PV to get so low that the air condenses into liquid.

I understand, it's just frustrating.

Well that didn't take long.

This +1000. We've been teased with better looks (or at least less bad looks) off and on for weeks. Not going to get too excited.