tombo82685

Yea they ticked a bit better for you guys. Seem like they consolidate the southern stream energy better thus making for a stronger low that heads towards KY area. Here is also a loop at h5 of differences between 0z euro and 6z one. Can see better consolidation of energy at base of trough. Also seems like there would be better spacing between that wave and the one by cali to limit it from breaking underneath the ridge to interact with southern s/w. Also, the northern vorts seem to be in a more suppressive orientation than 0z too.

I dunno I don't like those rmm plots. The continued COD bias they have had and they get side tracked with other noise in the atmosphere. Looking at that though, kind of agrees with Mike's Vp maps. Looks like current wave should hold into the IO from what I'm seeing. I guess the little convection in the maritime continent is what is throwing the rmm plots for a loop as to determine which is the wave to focus on? So basically they re caught in between both forcing mechanisms?

Looks flatter than 0z

Gefs look pretty good. Better timing of s/w not to deep into the nw flow which allows for better hgt rises. 24hr qpf mean off gefs

Ukmet certainly looks interesting. Stronger southern stream s/w it appears. Better hgt rises out ahead of it. Don’t see much northern stream involvement though.

No problem, the ssw effects right for us aren't as important as the mjo phases will do the job. I think we are going to need it more in feb if/when the mjo may get into unfavorable phase. I think thats what the weeklies were hinting at were effects from the strat for feb. It's something to watch in the coming runs because if they start backing off it's probably because they aren't coupling with the troposphere and sniffing out on the mjo progression.

From looking at the eps and gefs, there certainly seems to be an increase in hgts across the arctic domain signalling some possible -NAM effects from the SSW. The strat observe site only goes off the 0z gfs I believe, but it still isn't coupling with the stratosphere. By the 20th though you can see how the +nam area is starting to sink and maybe signalling some coupling possibly after the 20th. One thing I like about this ssw event is,usually with these type of events this time of year you get your wind reversal then shorty after the PV recovers. This isn't happening at all. The winds continue to be easterly at 10mb out to mid january. So we certainly have time for it to downwell still. Last Feb ssw took about 3 weeks for us to start feeling the effects.

The punt back to later January on the weeklies from the mid/late december runs IMO was attributed to missing the amplitude of the mjo and also possibly down welling the ssw effects to fast. The thing I'm curious about as we head into February is if the ssw effects propagate downward to the troposphere. IMO the weeklies are keying in on that occurring hence all the high lat blocking. At some point in late late January into February looking at the OLR on the VP plots, the tropical forcing isn't going to be conducive for cold. You can see by week 2 we are in a phase 2 look on them. Granted forecasting convection this far out is always a crap shoot in trying to figure out amplitude or what not. The strengthening of velocity potential close to the IO tells me MJO wave may possibly start to get stronger again towards start of February as we head into the IO and towards the maritime continent. Thats where the SSW effects may become key in keeping a favorable pattern going forward.

I saw this posted on twitter, it's off the 12z eps but may be a reason why the eps look like poo in the 10-15 day. Looks like after a short visit in phase 8 around jan 9th they re-ignite tropical forcing in the IO then go back towards that standing wave look in phase 5 that was so persistent in the back half of December

We all saw the eps in the long range and they looked like poo. I think though it's also good to note trends from one run to the previous. If you compare todays run to 0z there is a lot going on. There is definitely a favorable trend here where the eps are backing off on the lower hgts just off the coast which is making for a better trend in the pna. There is certainly some disagreement going on whether to have all that energy sitting off the coast or not. If all that energy continues to trend less and less you should notice a more meridonal flow instead of all this pacific jet vomit. The more energy bundled off the coast will bring a flatter flow and pac air. Look at the the notable trend here at day 10, 13, and 15. You can see the better ridging out west pulls the lower hgts towards the east coast which is what you would expect with a phase 7 look. It even closely resembles a phase 7 el nino look. So maybe the eps are starting to pick up on a better mjo signal and not trying to kill it. I'm just not certain if I buy the look of the eps at the end. My only though is the reason it's doing that is because its killing the amplitude of the mjo in phase 7 which I think is wrong. Hemispherically speaking we still aren't seeing the -ao signal show up on the eps. They do pop it for a couple days around day 10/11 then kill it and bring below normal hgts back. Thats needs to change too. now look at the euro back on dec 20, constantly being to bearish on the mjo and not seeing the full amplitude of the wave propagating though. Now look at todays run. Note the continued correction towards more amplification. So I think as the euro continues to adjust for this we see better looks, or atleast I hope. Anyways, just putting some food for thought out there. old new

I can't see the NAM stuff for the euro, but the issue has been can the stratosphere couple with the troposphere. Some of the papers I have read is that you want -NAM in the 100-300mb zone to truly couple the troposphere with the stratosphere for impacts to start occurring. Looking at the latest plot (today hasn't updated) we continue to be in a +NAM index in that zone meaning the stratosphere isn't propagating down, atleast, yet. This could certainly change as we go out further as these impacts for the east usually take weeks to occur. You definitely want to keep an eye on this though. Not all SSW's have a response on the troposphere, think I saw 40% don't. They refer to them as nSSW's. Here is a good link to SSW's. https://simonleewx.com/2018/12/27/not-all-ssws-were-created-equal/