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Nov. 27th - Nov. 29th Upper Level Low


LithiaWx

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Yeah, an upper closed off low is never good for us, if your wanting wrap around precip. I never was looking for snow east of the mtns in NC on this one..its all west of the Apps and up to the chain. In fact, we'd have a less shot at some flakes on the wraparound than say CLT or GSO would. We get dryslotted rapidly . But boy do we get the rain before the cold comes in!

Yea major rain for Monday if the GFS is correct. It's always interesting to see that dry slot so pronounced though!

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Awesome 12Z GFS run, looks like we are going to get our ULL!!!

I wouldn't say it's awesome for us. It's good it's finally come around to all the other guidance but for those in Ga we need this low to be further south if we want anything more than a few flurries, which this run would give us.

850mb to 700mb RH looks ok but it's not great. More than likely the decent snow showers would be confined to the far north/northwest,tn/nc border counties. But at least it finally has the upper low at least.

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Yea major rain for Monday if the GFS is correct. It's always interesting to see that dry slot so pronounced though!

Just looked at its qpf totals and they're way under-done for eastern GA and the Upstate on this, otherwise, this run did exactly as I thought it would. Takes the cutoff down to 528 heights (impressive!) by the time its in southern WVa. and absorbs into the next trough diving in the Lakes, so here comes the cold air. It develops a PV over Hudson's Bay and a tall PNA ridge out west over the eastern PAC. That sets the stage for storms to ride southeast and mix with colder air to its north, possibly pullin down colder air. We'll see if the rest of the run does that.

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I wouldn't say it's awesome for us. It's good it's finally come around to all the other guidance but for those in Ga we need this low to be further south if we want anything more than a few flurries, which this run would give us.

850mb to 700mb RH looks ok but it's not great. More than likely the decent snow showers would be confined to the far north/northwest,tn/nc border counties. But at least it finally has the upper low at least.

Hey we count as Georgians too! :thumbsup: Haha jk Lookout!

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I wouldn't say it's awesome for us. It's good it's finally come around to all the other guidance but for those in Ga we need this low to be further south if we want anything more than a few flurries, which this run would give us.

850mb to 700mb RH looks ok but it's not great. More than likely the decent snow showers would be confined to the far north/northwest,tn/nc border counties. But at least it finally has the upper low at least.

I agree it is not an awesome run for Georgia but for a weather lover it's pretty awesome. also close enough to make a run farther north to see some decent flakes falling if this verifies. I'd take a few flurries and run with it. This would break last years first snow flurries for mby if I get a few flakes.

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With the setup the GFS (and most the other recent models have), a strong developing upper low in western TN that slowly moves across the state and then lifts toward West VA should have no problem in making the first major snowfall of the season for the Apps of Wva, Va, NC and TN. Most of the TENN Valley should get a good period of snow showers and maybe a period of solid, steady snow (ground is warm, boundary layer warm, etc). but I'm sure now that this is a major snow for some, and good period falling snow for many on the west side of the Apps and flurries Monday night down to ATL region as long as the models aren't too far south with their progs. It matches latest ensembles. Also the models are notorious for not handling cutoffs well at all, even when they get the 5H look correct, they miss moisture panels in our part of the world. It depends on how the moisture wraps around fully and if it can get directly under the cold core , sometimes they can and some times that moisture doesn't. This one looks loaded with spiraling vorts in the center, and I wouldn't be surprised to see a Low pressure pop up on the coast of SC or NC later on , not shown yet. That would be good for central and northern NC and into VA if you want to see some flakes.

For the upslope regions of TN, NC: Its a nice one. Some 8" totals pretty common maybe a foot in the best upslope spots, since its going to be a 2 day event (Mon and Tue).

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I agree it is not an awesome run for Georgia but for a weather lover it's pretty awesome. also close enough to make a run farther north to see some decent flakes falling if this verifies. I'd take a few flurries and run with it. This would break last years first snow flurries for mby if I get a few flakes.

Furthermore, for NW GA, this gives a solid 1-2" of qpf in the form of rain. It is still too early to be declaring rain evil. The offiical "evil rain" season doesn't start until 12/1 lol. Yes, at that point rain becomes nasty/unwanted even though 90%+ of all wintry precip. liquid equiv. is plain rain in the ATL area. ;)

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Furthermore, for NW GA, this gives a solid 1-2" of qpf in the form of rain. It is still too early to be declaring rain evil. The offiical "evil rain" season doesn't start until 12/1 lol. Yes, at that point rain becomes nasty/unwanted. ;)

No matter what the date...rain is not evil to me :wub: I've got my fingers crossed I will reach the ever elusive .25" mark :lol:

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This run might also be interesting as Robert said downstream. At 192 it looks like it might be setting the table for something good. Never mind it just brings more rain..but at around 240 it does bring the cold air down again. Who knows how legit that is though since the cold air always seems a week away.

Its a pattern change. Tall PNA ridge out west, so we're heading into colder overall pattern for sure. You're looking for snow huh? Ha, well don't trust the models on that just yet, but the pattern is heading that way for part of the country, esp. the Plains and Tenn valley in the next 10 days. Keep an eye on the storm after this one. That's quite a cold outbreak its showing. Active times ahead with that huge ridge out west. The ground here is pretty wet, and has been all Fall (and last Spring) , so this is one very unusual Nina for this region.

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Its a pattern change. Tall PNA ridge out west, so we're heading into colder overall pattern for sure. You're looking for snow huh? Ha, well don't trust the models on that just yet, but the pattern is heading that way for part of the country, esp. the Plains and Tenn valley in the next 10 days. Keep an eye on the storm after this one. That's quite a cold outbreak its showing. Active times ahead with that huge ridge out west. The ground here is pretty wet, and has been all Fall (and last Spring) , so this is one very unusual Nina for this region.

With the pattern change though are we still going to get this barrage of weekly systems? Or will go into something more passive like we've had the past few winters where you get one storm every 2 weeks or so? It's seems they still want to be churned out but is that not a symptom of the current pattern we're in?

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The 12Z Canadian is back to a SW LA cutoff solution. As noted by the HPC this morning, the guidance is throwing major curveballs from run to run. We may not know exactly how this all plays out until the U/L actually cuts off. What a forecasting challenge ahead.

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With the pattern change though are we still going to get this barrage of weekly systems? Or will go into something more passive like we've had the past few winters where you get one storm every 2 weeks or so? It's seems they still want to be churned out but is that not a symptom of the current pattern we're in?

Last 2 winters were different (so far) because they were more stable patterns and driven by one flow (well nino had 2). This pattern so far this fall is very volatile, as wild as I've ever seen it. Look at the number of significant to major cutoffs since late August I believe. Quite a few. Highly unlikely to have this many, and they continue to show up. Even for a nina, its a lot. So odds are , the pattern change will be brief, but I don't know. So far looks like we'll have a good week to 10 days of basically PNA pattern, which means colder in Canada and central US probably, but the southern states could waffle between the warm and colder sides, as we've been doing. If you've noticed, the ECMWF wanted to keep a ridge over us a lot, and yes we have had some record highs, we're also having enough cold on the backside of all these fronts such that we're probably going to even out to "near normal" on temps this month. Some areas of NC may end up below, some above. I think the storms will continue until further notice. The amplitude, or ability of the flow to get ampped, is just too overwhelming to get dry for very long here.

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The Op GFS is now an eastern outlier- the majority of the members are west of the Op. This lends some validity to the low first closing off well west/SW like the new Candian and earlier Op Euro showed- which is bad news for snow in GA, but good news for heavy rain.

And what a rain event that would be. Eastern Alabama and much of GA esp. western and north half would get more rain than they need I think with that setup. Not sure if it will cutoff that much though the difference will be tomorrow in how much northern energy is diving toward Ok and western Mo.

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And what a rain event that would be. Eastern Alabama and much of GA esp. western and north half would get more rain than they need I think with that setup. Not sure if it will cutoff that much though the difference will be tomorrow in how much northern energy is diving toward Ok and western Mo.

Ha! Never more than we need, in Griffin, anyway :) I doubt you'd have felt that way when Shelby was becoming the Namib, lol. The reservour is as low as I ever seen it, meaning the creeks feeding it are starving, even after a few inches of rain in recent weeks. I think we need a good 3 or 4 inch rain bomb every few weeks to start to recover. I'd rather a slow moving sure fire GOM low, but a wandering, elusive ULL will do in a pinch :) T

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Tony if the new ECMWF is right you'll get some nice rain. Its cutting it off over northern LA. Similar to GGEM now. By 84 hours its around 546, centered over JAN. Probably cold enough to turn rainshowers over to snowshowers monday night in Ark, n. La and western.nw MS. No matter how you slice it on the models, major rainfall in ATL to BHM regions i think.

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at 96 hours a nice 3 to almost 4 contour bowling ball low centered over Ms/nw AL border so the timing would be overnight Mon night for the snow in Ark, n. Ms, and west/Middle Tn for snow or snowshowers. The nw side is usually the best side for lift, so western Tn and central to eastern Ark would probably get the most snow in this setup, ironically go north into Indiana and its rain.

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By 108 hours (wed night) a pocket of -4 is over nw GA so thats pretty cold, and the cutoff moves directly overhead the southern apps (n GA/ sw NC/east TN). Colder air from the next system is joining it so the whole atmosphere is cooling as it starts to get absorbed, and this new lift helps precip in Ky and TN...so pretty sure that would be wrap around snow getting squeezed out from 2 sources of lift. Deformation axis!

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in the big picture its similar to GFS just further west to start and not quite as cold. Still the track of everything would bring northwest side snow to Ark, Ms, Al, Tn, Ky, and some minor wraparound to GA even down to ATL overnight Tuesday I think, and the Apps getting it as the system goes up the coast, not to mention southern Ohio Valley, pretty good axis of convergence there eventually. Wouldn't rule out flurries in NC or SC early Wednesday as the ULL comes across but the good moisture would be on nw side.

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Last 2 winters were different (so far) because they were more stable patterns and driven by one flow (well nino had 2). This pattern so far this fall is very volatile, as wild as I've ever seen it. Look at the number of significant to major cutoffs since late August I believe. Quite a few. Highly unlikely to have this many, and they continue to show up. Even for a nina, its a lot. So odds are , the pattern change will be brief, but I don't know. So far looks like we'll have a good week to 10 days of basically PNA pattern, which means colder in Canada and central US probably, but the southern states could waffle between the warm and colder sides, as we've been doing. If you've noticed, the ECMWF wanted to keep a ridge over us a lot, and yes we have had some record highs, we're also having enough cold on the backside of all these fronts such that we're probably going to even out to "near normal" on temps this month. Some areas of NC may end up below, some above. I think the storms will continue until further notice. The amplitude, or ability of the flow to get ampped, is just too overwhelming to get dry for very long here.

Thanks for the info. Euro is certainly looking interesting for that ULL...wish I wasn't on the bad side of the dryslot I wouldn't mind seeing at least some flurries out of it whistle.gif

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if the cutoff begins pretty far west, at some point we'll be getting worried about too much rain . I know about everywhere could use it, but this could seriously be too much rain in Ala, GA and the TENN valley, and southern Apps. The models are sometimes too quick to move out ULL's as well. This one has a great tap to the Gulf , perfectly positioned.

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