Holston_River_Rambler

Happy Thanksgiving from Morgan County:

Some chatter about the long range EPS in the MA subforum, so I thought I would post it here. Interesting pattern if it verifies:

Remember when the Euro showed this? Pepperidge farm remembers:

Sorry for the flurry of posts, but just thought of one more thing to add. Well more of a question. Do y'all think there is a relationship between the upper level divergence forecast over NE South America and the Caribbean, and the -NAO that the ensembles are also wanting to build along the same longitude?

Out in ye olden tropics, looks to me at least like the MJO wave has moved into 5/6: At that pace it should make it to the more favorable regions in about 2 weeks. Still some convection holding on in the central and western Pac too. I don't have a clue what it is, but there seems to be some favorable aspect to that environment. I will be interested to see how all that looks in a couple of weeks. The RMMs suggest that it will do what it did last time and die out: The above is the GEFS, and the EPS looks pretty similar. But let's remember that the low amplitude treck it just took through the COD produced enough cold to probably even out the temp anomalies in November by the end of the week. The EPS and GEFS also want to argue for significant tropical forcing over NE South America and the Caribbean in about 10 days: Not really sure if that is MJO related or something else, but it will be interesting to see how and if that modulates the pattern.

The GFS has been handling the Friday system weirdly over the past few runs, but the Euro has been more consistent. Either way , the main low is pulled west of the TN valley, like Carver's said, but hopefully the Euro has a better handle on the pattern and the GFS is holding the system back too much. It's November, cutters gonna cut. I feel like its always been some version of a cutter, just a question of can the whole shortwave eject out of the SW at once, and how much energy gets pulled in on the back side as it strengthens and pulls away. It is East TN and it is a chance for snow, so what can go wrong, may in fact go wrong, lol. Hopefully at least a good upslope for the eastern mts and NC.

Past that system, the GEFS and EPS seem pretty -NAO happy past day 10: Canadian ensembles, not so much:

it's a situation where it would be fun to see how many Ensemble members show such stout blocking and which don't, to give us the more washed out meh look. Is it like a big snow on the ensembles where one or two with major blocking skew the mean, or more of an even split? Not sure there is a model service that gives individual ensemble members H5 looks though.

You -NAO lovers are gonna love the 6z GFS: Of course it is still waaayyyy out there.

Is this the time where we talk about the Euro holding back shortwaves in the SW too long

12z GFS FTW:

Euro had an interesting evolution at the end of its run overnight: Obviously not a great look for anywhere outside of SWVA and elevations, but at least it's something. Hopefully it ends up better than the last one I was interested in, lol. GFS quite a bit different with its evolution of the system.

I am not totally 100% sold on fighting a crappy Pac just yet. Now, I may be 90% sold on it, but not 100%. I want to see what happens if the MJO wave can catch up to some of the convection in the Pacific. I suspect by this time next month the tale will be told. Seems like around this time for the past couple of years like I notice some convection in the better parts of the Pac and then it will just fizzle out. Could be that will happen in this instance too. One of the mets in the general forecasting part if the bigger forum seemed to think there was also a chance that the dying La Nina might allow for the MJO to make it to the better phases, at least later in the winter, since it had a strong pass this last time.

Interesting line up of convection in the western Pac: The majority of the tropical convection is still in what we would call phase 4 on the MJO RMM plots, but last time I looked a few days ago the whole tropical Pac was pretty empty. Maybe we can get some of that to hang around while the MJO wave slowly percolates eastward? Might help facilitate some of that blocking y'all been talking about. GFS pushes it even further east to the central Pac over the next few days: Euro does the same, but it eventually interacts with storms N. of Hawaii: Of course it could also be too early in the season for any of this to matter, but that's all I have while we wait to see how all this evolves over the next couple of weeks.

95/96 analogue will save winter and basketball! It is mighty!

I guess I should have looked at the 0z GFS before I went through all that above lol:

The NAM has definitely trying to honk on a flurry or two for me. Are you atop a mt. down near Soddy-Daisy @Knoxtron? I would be down for what the NAM is selling. MRX is kinda-sorta interested in the next system: The main question with this system will be temperatures at the onset of precip Tuesday morning. It will be a race between precip arrival and warm advection bringing surface temps above freezing. Model soundings show a prominent warm nose that suggests some freezing rain potential for a brief period in northern sections early Tuesday, but model differences in precip onset timing make this very uncertain (NAM being faster with the northward spread of precip than the GFS). For now, the forecast will mention snow or a rain/snow mix early Tuesday morning for the mountains, SW VA/NE TN and the northern Cumberland Plateau. Overall, the potential impact appears low at this time. Any precip with this system ends Tuesday night. I'll take a wintry mix too! This Tuesday-Wednesday system would have some better potential for NE TN and SW VA, except for the dreaded Lakes low, messing with the mid levels. But it at least looks like western areas Arkansas and NW TN will get a shot of snow again. I'm slightly interested in the Fridayish time frame. Euro and GFS show a jet streak and broad vorticity advection, but at this time there's nothing upstream (i.e. blocking) to amplify it enough to throw precip back into our area: A couple EPS members show accumulating snow for Elizabethton (using that city since it is in the far eastern part of the forum area), but several show snow falling, even if only flurries. Several GEFS members show a general 1-3" for Elizabethton too. If that were to happen, if might look something like this: EPS member 49: To be fair that is only one member, but it is an early one this year, and I think even though it isn't likely, it is plausible, given what happened with this system that's coming through today: The above is a 16 frame gif of the trend of the GFS for 18z today. You can tell the mid-upper level pattern isn't changing too much overt he 16 runs (maybe I'm wrong, but that's how I read the thickness lines on the map), but as we get closer to verification, the model is like "oh, maybe there will be some precip. there and, oh yeah, we'll move it a little bit NW too." it's not like it's that unusual for precip to make it back a little further NW that models show, but ever situation is unique and this could be a whole lot of nothing. Webb also thinks there's a shot, (at least for western NC and S. VA) so something to keep an eye on as a warm up for the season:

If nothing else, finally get to get some fires in the fireplace for the Holiday mood. Euro looks nice and chilly especially long range. Nice Aleutian low, AK ridge, and room for something to sneak in across the southern US and perhaps time it right with a cold HP from Canada.

Euro and GFS are pretty optimistic for plateau areas for rain Friday: Euro: GFS: The occasional snow chances that had been showing up aren't looking so hot right now, but that could always change. At any rate, more precip is coming next week too to help with the drought.

18z GFS is much excite: 7 days isn't too bantry. ? Let's just add that the Euro looks a smidge different for that time frame. Might even dig out the old ensembles tomorrow AM.

Here ya go: source for those interested: https://stratobserve.com/misc_vort3d It usually refreshes once a day with 0z GFS

Yeah, I actually looked it up and was thinking about gifing it, but hadn't got around to it yet. I will later this PM.

I guess it's that time again, lol. The Euro's take on the MJO is pretty classic La nina: It hits the phase 8 area and it's like, "ohhhh noo, can't go there, back to 5, 6, and 7." I do remember that when we have it hang round in 6 in high amplitude it can favor the sort of SPV split the models are showing is possible. Soon I'll have to go look at Anthony Masiello posts about Siberian night jets and other such things, lol.

I hadn't even looked yet at SPV stuff this early. Just looked at it this AM and yeah its getting thwacked around even this early. When was the last one we had in Nov/ Dec? At 50mb the Euro gets a good N. European ridge going in about 7 days: GFS goes on to get a pretty good split at that level through the end of its run:

Griteater has some early morning winter thoughts this AM: