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Everything posted by Carvers Gap
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February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
Pretty massive snowstorm for portions of middle and west Tennessee on the 0z Euro around 200. Still way out there, but worth a look. 6z GFS has the ice/snow deal but over the Ohio River Valley on this run. Interesting development is the 6z GEFS flipping to an eastern trough d10-15. Ensembles are bouncing around all over the place. Something to watch. EPS looks like a good compromise at the moment with a weak trough out West. Still looks like a trough out west after Feb 10th, but again its holding power is in question. We do know from past experience it does not like to leave. That -EPO might try to kick it if it isn't too tall. Jax with some discussion about possibilities down the road - the next GEFS run backed those ideas up. -
I know the Smokies had blizzard conditions during Hurricane Sandy, but did they actually hoist a blizzard warning during that event? They had 2' with high winds up top.
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February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
The EPO is quite negative on both the 18z GEFS and 12z EPS ensembles teleconnection graphs on WxBell. Been trending stronger for a couple of runs now. All of that is pretty loose optimism. There are definitely strong reasons to be pessimistic. Just adding some food for thought. -
Those folks in SW Mizzou have to feel a bit jaded...And eastern Idaho must have a high threshold. They have been hammered this winter with massive drifts and blowing snow. Hawaii surprises me when I first see it, but just for a sec. Then I remember...big, tall volcano sitting all by its lonesome in the middle of a big, active ocean.
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February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
The benchmark of what a great winter is for me. Was sitting in Saturday school(making up snow days) with like 4-5" of new snow on the ground and still snowing. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
The good thing is I don't think at this time that we are going to see an air mass anywhere near as cold as that one nor as prolonged. I remember driving to UT on the interstate that was down to 1-2 lanes for a couple of days, because the snow was frozen solid and wouldn't plow and wouldn't melt with salt. I think for now, just plan on a warm SER. I just hadn't realized that LR modeling had such strong, sprawling cold highs pushing eastward under the SER. Now, we saw this in early January and it never verified. So, I am taking these with a grain of salt until I see them backed up over the next 4-5 days on multiple runs. But still, great to talk about and interesting. On our wish list, as Mackerel noted, we want to see those big highs in play. Without those or some really cold air, those looks don't occur. But gives us something to watch anyway! -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
Man, those were the days. Great decade with some great weather. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
Thank you. Here you go. This the MSLP anomaly on the 12z EPS. The second graphic is what is under that SER on the EPS run. If you have that feature, what is under the 18z GFS op run is wild. I wouldn't have though to look had it not been for the 18z GFS(which for those rolling their eyes...we know). That high sprawls on all three models. Not sure I buy all of that. 500 usually wins, but even the ensembles have some impressive highs(HP) for ensembles. That is a 1040+ hp on an ensemble heading south out of Alaska. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
@Holston_River_Rambler, I was looking at the d10-15 on the 18z GEFS. At 500, it backed it up. The CFSv2 at 12z has the same deal. Cold is pressing and the airmass is colder. You know, I didn't look at the 12z EPS, but it has the same setup. The cold is pressing under the SE ridge. Not sure I buy that...again, we saw that once early in January on modeling and it busted. The 500 pattern won. So, I think we have to take into account that modeling has been far too cold at LR and we have to take into account(weighted much less obviously) that modeling was too warm during a pattern change in November. Holston, do you think you could post a gif of the daily mslp anomoly from d10-15 of the EPS(edit)? Watch that high spread out. I didn't look at the surface. The trend at 12z is for a much bigger high in the northern Rockies that spreads eastward. 2m surface temps and temp change reflect this d10-15. Pushes all of the way to the Apps. Holston, I think the WxBell analytics page might have more increments and provide a better look on the mslp anomaly. If you need me to, I can just post a screen shot. Need the daily version vs 7-day version. Thanks again. @weathertree4u, that is ice city verbatim. They have been cutting trees off power lines in my neighborhood for weeks on end. It is a sign! LOL. Overall, I suspect if this occurs it happens over the Ohio Valley...but at least it is interesting. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
LOL!!! Ya think? And of course, I agree. I actually think that is the snowmegeddon pattern but we somehow get on the right side of the pattern. I would actually be nervous in Akron, Ohio, though. That strung out front is on almost all modeling. Prob somebody to our north is going to be shoveling. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
This run isn’t gone be denied one last shot. 1053 high crashing down into MT to end the run. After these crap d10 ensemble runs today, I raise my glass to a DGEX throwback run! Verifation score might take a hit. Someone post the snow map with the best snow algorithm! Full d16 map...nothing to lose, right! -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
These snow amd ice amounts are gonna be just silly. #happyhourridesagain -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
1054 high over MT at 300. Let’s see if future runs have that. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
18z GFS showing what happens when the trough does not get hung up in a feedback loop like it did 12z. That is one potential option in a positively tilted trough. If the cold pushes, things could get interesting. Multiple ice storms across the SE post d10. I think what is happening is the cold(prob overmodeled) is pushing at the surface. We have seen this once before this winter and it did not verify. The 500 map trumped the surface map in reality. Still, that shows what can happen. Likely? Prob not. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
12z EPS basically has the same look for an ensemble out to d10. Observable changes after that which are basically a variation of the same look from the past few days. After d10 the EPS digs the western piece of cold and really buries the trough in the West - which has been discussed as a possibility ad nauseam. So, the nice trend of cold being centered over MN at 300 is now centered over WY/UT. Massive AN heights in AK and GOA. All anomalous features over NA are much more amped than 0z. Still looks like two amps from d10-15 regarding where to put the cold. Eventually, the EPS tries to pull the cold back to HB at 318. But overall, the message of the EPS is, "You had better score in early Feb." By the end of the run strongly +NAO, +PAN, ++AO, retrograding(westward EP). If there is one slight hope, it is that the EPS is dragging its heels in the West, but I have my doubts with that. But since we know the models are not verifying well at d10-15 at times, I wouldn't lose sleep...it will change. @Holston_River_Rambler, any PV updates. We may need it after Feb 10. Interestingly, the Weeklies look to have nailed the MJO for the middle of Feb. Let's hope they are right about what comes after. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
At 240, there is a near perfect negative til trough at 500 (vort maps are a nice look) as it is leaving Alabama. That is a big storm look. But it is at 240. If it is there in a few more runs, I will post a map. I assume most of you can find a site and give it a look anyway. If new, try Pivotal Weather or Tropical Tidbits for Euro maps. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
12z Euro just ran. It is not too dissimilar to the GFS. The trough at 500 goes neg tilt late in the run. So who knows if that holds. Big difference is losing the pseudo -NAO mid-run. I say pseudo because it is only there due to the HB block being lifted out. That changed the configuration of the run and changed the config of the window for a storm. Again, I will say that we are hunting a window for a storm. Once it became obvious there was nothing to hold the cold in place, were are basically looking for a winter storm as the trough enters or leaves. Losing blocking up top causes problems with cold sources and with forcing troughs underneath. -NAOs matter when hunting EC storms but a 50/50 low(low holding just north of Maine) will do it. Something has to block the storm south. Anyway, overall synopsis is the trough digs into TX and holds slightly more than 0z. What that does is to allow it to do is sharpen the trough. Energy hits the bottom of the trough and there you go. If you want a lot of cold, that is probably not your run. If you want a trough that digs enough to force a (SECS) storm to track, that is your run. Of note, there is another piece of energy at 192 that could also work. So, it is similar to the GFS that a couple of pieces of energy start beneath us and work up. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
BTW, the reason I am not buying that after d10 is not because it doesn't hit MBY, it's just the aforementioned progression looks really odd. Anyway, that 18z run at least gives us one possibility of maybe what is happening(excluding the trough digging to Guam) under the hood within ensembles that show the ridge dig west after d9 and then press eastward. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
That ridge in the GOA is impressive impressive though d10+. Again, just an odd run at that point. Probably will stick a trough back in the East late in the run, but its progression is unlikely after 240 - which is not surprising given that we are talking about an operational at range. Sure enough big ice storm late in western areas of the forum. Again, not really buying much after d10, but interesting. That was probably five sentences too much, but there you go. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
And then beginning at 240, the GFS digs a system at 500 from Idaho to off the coast of Southern California. West Coast version of a Miller B? I think there will a trough digging, at least initially out there, but that looks like a feedback issue. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
Way out there...the setup on the 12z GFS at 200 is not terrible. It is the third of three waves that pass progressively more eastward between February 4th and 8th(5th through 8th in MBY). That system would likely not be fighting to overcome crazy warm temps. Looks like waves 2 and 3 are something I will watch for MBY. Areas in west TN and Arkansas would need to watch the first wave per the GFS. Right now, it cuts right over west TN. But if the trough speeds up, that could change. It sped up just a hair after several runs of slowing down. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
Great question. I will start the discussion, but am certainly not the final say. I am no fan of La Nada. "Meh" is my word for those years. Some call this year a Modoki El Nino, but I think it will be classified officially as a La Nada. The problem this year is the Modoki is centered right over the top of the phase 6 MJO! LOL. Not good. I think that ENSO 4 region has caused havoc along with a record IOD. It(the phase 6 MJO region) is/has been a near constant area of convection and rain. I think what has caused modeling problems is the rest of the MJO has propagated normally while phase 6 just sits there and stews. It has trumped all other phases that have fired. Now, I do think modeling does much better when Nina or Nino locks in as the pattern is fairly consistent, especially during either winter or summer. Shoulder seasons are always a crapshoot. If you haven't already, search for TyphoonTip's discussion about the SST gradient in the Pacific. We really have not had a moderate Nina since January of 2012 though January of 2018 was close. Our last strong La Nina was January 2011. Interestingly some of those great winters around the 2010 timeframe occurred in between some moderate to strong La Ninas. I am a big fan of weak La Nina ENSO patterns. Like anything they don't always work out but they can be very cold at times. That said, I think the Super Nino of 15-16 really warmed the Pacific and has screwed up the temp gradient there. It is above normal. We really need a strong Nina to wipe that out. We haven't had one in nearly nine years. IMHO, until that temp gradient gets cooled...we get what we have had the past two winters which are analogs(based on ENSO) that don't work. Jeff talked about analog problems recently. To paraphrase Typhoon, he basically said that a weak Nino needs a stronger gradient/transition to cooler water. Right now most of the Pacific is warm, and the gradient between the warmer SST area and a cooler one is non-existent as much of it is AN. I think much of the reason for that is because we have not had a strong La Nina to cool the Pacific and reset the gradient. Now, strong La Ninas are usually warm winters here, but we might need to suffer through one of those winters in order to get a better gradient. Next winter's ENSO? Probably a good question for @jaxjagman. I have seen commentary for both a Nina and Nino. I have read some information that when we exit the solar min and get closer to the max that Super Ninos are possible - hopefully several years from that. I have also read that the winters just after a solar min have more blocking. I won't hold my breath, but we will see. Next winter's ENSO is a question mark for me. Looks like ENSO neutral is forecast through summer and into fall with slightly negative SSTs. If forced to make a summer forecast based on that alone - As the summer progresses we might have increasingly dry and increasingly AN temps. Might be a normal start and a hot August and September. https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf https://ggweather.com/enso/oni.htm -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
The EPO on the EPS yesterday was positive. Overnight, it flipped negative as evidenced by the pic below. To give you an idea at how much modeling is bouncing around. In the medium and LR, the EPO has reversed large portions of the EPO with reach run going back to Jan 26. Overnight it looked like this. Will it stay? No idea. This started occurring about the time we started talking about the PV splitting. The AO is strongly positive which I wonder if that will reverse given the nature and structure of the upcoming trough. One index we have not spoken about enough is the AO. It has been quite positive this winter and is forecast to remain strongly so. That said, observed AO readings are currently of of sync(below) what predicted values on the CPC site. Regarding the pattern after the 10th, let's keep an eye on the EPO trend as that seems to be the only thing available that can help us at times. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
One thing to keep an eye on is the EPS trend weakening the area of BN heights that slides into the West after d10. For three straight runs it has displaced the stronger heights northeastward towards eastern Canada. That gives modeling a couple of options. It could be that modeling will bring back an eastern trough periodically or it could pull the cold up to the Hudson Bay. If it pulls up to the Hudson Bay, heights will likley build under the area of BN heights w periodic shots of cold pinwheeling into the SE and East. @Holston_River_Rambler, another thing to watch is if the TPV splits...modeling could flip on a dime if modeling thinks that is going to hold. Sometimes that flip is good(see 2018) and sometimes it is bad(see Jan 2019). In both cases modeling had pretty consistent looks and then bang...everything was upended within about two suites. If the SPV occurs in early Feb, not sure it can help us as the lag of effects into the troposphere would possibly not get here until mid-late Feb. That said, seems like the strat and troposphere are coupled right now. If it stays that way, the effects could be immediate. And then sometimes SPV splits don’t translate to the troposphere at all. I suspect an SPV split this time does translate down. A TPV split can work like an electrical breaker. Flip that switch and things on modeling often switch dramatically. So circling back, having the BN heights on the EPS building over the HB might be a hint at where one of those PVs ends up. Speculation on my part, but something I have noticed. -
February/March 2020 Winter's Last Chance Thread
Carvers Gap replied to John1122's topic in Tennessee Valley
I actually still like the February 5-10 window. Here is the side-by-side comparison of the past two runs at 500. 0z was actually colder with the initial front on the 5th. And again, without a -NAO it is going to try to lift out. This is at 18z on February 5th. One positive is the trough and initial front sped up a bit and deepened quite a lot compared to the previous run. The run-to-run change at 2m was actually net colder on the Euro OP for d5-8 when compared to 0z. I would post the R2R maps of those days, but I think you can get the picture by looking at the comparison at 500 at 186. New run is on the left. For once, the overnight run during this time frame actually improved.