Carvers Gap Posted January 19, 2017 Share Posted January 19, 2017 12z EPS is a good example of what I mentioned earlier....and the uncertainty thereafter. Ridge rolls east in what is an apparent reload of the pattern...but I lean that way in my thinking just barely. Tough to tell if a trough is setting up in the west or just passing through. Based on cold reloading and heading southeast out of northern Canada late in the run...looks like the western trough is transient. Though I am not certain. This feature(eastern ridge) is shown on all ensembles to some extent late in their runs. Maybe the weeklies will shed some light on that. On Monday, they showed something similar and brought the trough back in the East shortly after. However, the Weeklies on Monday pulled the PV so far north that it allowed the pattern to go zonal. The MJO looks to have nailed the upcoming cool down. After this trip to 8,1,2,3...it goes into the COD and tries to come back into favorable phases after a break. The dropping SOI is a good hint. It is at -33.54 today according to Long Paddock. Link to comment Share on other sites More sharing options...
Carvers Gap Posted January 19, 2017 Share Posted January 19, 2017 As suspected due to the 0z run...Weeklies are a crap fest. Week 2 has a decent trough as modeled on the operationals. Week 3 goes zonal. Week 4...the eastern trough re-amplifies. Form there, it is a western ridge and eastern trough w above normal heights and 850 temps. In other words, we have two time frames that look like winter, weeks 2 and 4. After week 4, no BN heights are found in all of North America, even w the trough. The last gasp is that maybe the Weeklies are having their usual disconnect between the pattern and temps. We have two time frames to score and then it looks like prolonged meh. Link to comment Share on other sites More sharing options...
Carvers Gap Posted January 20, 2017 Share Posted January 20, 2017 A better description, but no less ugly... Link to comment Share on other sites More sharing options...
John1122 Posted January 20, 2017 Author Share Posted January 20, 2017 29 minutes ago, Carvers Gap said: As suspected due to the 0z run...Weeklies are a crap fest. Week 2 has a decent trough as modeled on the operationals. Week 3 goes zonal. Week 4...the eastern trough re-amplifies. Form there, it is a western ridge and eastern trough w above normal heights and 850 temps. In other words, we have two time frames that look like winter, weeks 2 and 4. After week 4, no BN heights are found in all of North America, even w the trough. The last gasp is that maybe the Weeklies are having their usual disconnect between the pattern and temps. We have two time frames to score and then it looks like prolonged meh. Weeklies themselves are a massive crap shoot. Even the OP only verifies the 850mb temp at 25% accuracy at 5 days. The Weeklies at their lead time are probably not a whole lot more accurate than placing cold/warm/wet/dry on a dart board and applying that to whatever region you're forecasting for at 25-45 days. Link to comment Share on other sites More sharing options...
John1122 Posted January 20, 2017 Author Share Posted January 20, 2017 In the closer range the GFS is getting close to a system in the shorter range. It's close at 168 to 174 with borderline temps and moisture. Possibly what the Euro was hinting at around 200 a day or so ago. Link to comment Share on other sites More sharing options...
Carvers Gap Posted January 20, 2017 Share Posted January 20, 2017 23 minutes ago, John1122 said: Weeklies themselves are a massive crap shoot. Even the OP only verifies the 850mb temp at 25% accuracy at 5 days. The Weeklies at their lead time are probably not a whole lot more accurate than placing cold/warm/wet/dry on a dart board and applying that to whatever region you're forecasting for at 25-45 days. I see your point, but I generally do not agree with that. It is a pretty good forecasting tool..about as good as one could expect. It appears it modeled correctly the upcoming pattern where the trough is leaving the western US. It seems to have accurately caught the relaxation after the upcoming cold shot almost two weeks before the operationals "saw" it. IMO it has missed "big" twice this winter...once w wall-to-wall cold portrayed a few runs ago and once in December when it missed the western trough. Other than that, it has been decent. Its weakness IMO is not seeing cold, very warm biased. Maybe that is in play here. One other weakness may be that it likes to almost default to AN heights during winter in the Davis Straits that don't verify often. Where it is most effective is in modeling the 500mb pattern around the NH. For a model that runs to 46 days, I am not sure we can asked for much more. But it makes good sense on this run...I just don't like the outcome. It ends the long overdue pattern in the west. It sends warm anomalies to AK from eastern Canada. It puts a trough in the East and builds a PNA ridge. But as we have seen all winter, no help in the Atlantic and the cold in the East does not hold. Even a -EPO is not holding the cold. As Bob Chill has been saying in the MA, we have gotten away w bad teleconnections during the past few winters. But generally, a ++AO/+NAO is not good for winter wx on the EC. Now, these two time periods modeled on the Weeklies are juicy...but will they have precip for the mid and southern valleys? It has been consistent in marking these two time frames. So, we have a shot at some winter wx. One good Miller A and nobody remembers the lack of tracking. Link to comment Share on other sites More sharing options...
Carvers Gap Posted January 20, 2017 Share Posted January 20, 2017 29 minutes ago, Carvers Gap said: A better description, but no less ugly... If you are looking for a sliver lining...PSU mentions that there may be conflicting signals "washing-out" things. Great comments. Like I said...better than my description. Link to comment Share on other sites More sharing options...
John1122 Posted January 20, 2017 Author Share Posted January 20, 2017 1 hour ago, Carvers Gap said: I see your point, but I generally do not agree with that. It is a pretty good forecasting tool..about as good as one could expect. It appears it modeled correctly the upcoming pattern where the trough is leaving the western US. It seems to have accurately caught the relaxation after the upcoming cold shot almost two weeks before the operationals "saw" it. IMO it has missed "big" twice this winter...once w wall-to-wall cold portrayed a few runs ago and once in December when it missed the western trough. Other than that, it has been decent. Its weakness IMO is not seeing cold, very warm biased. Maybe that is in play here. One other weakness may be that it likes to almost default to AN heights during winter in the Davis Straits that don't verify often. Where it is most effective is in modeling the 500mb pattern around the NH. For a model that runs to 46 days, I am not sure we can asked for much more. But it makes good sense on this run...I just don't like the outcome. It ends the long overdue pattern in the west. It sends warm anomalies to AK from eastern Canada. It puts a trough in the East and builds a PNA ridge. But as we have seen all winter, no help in the Atlantic and the cold in the East does not hold. Even a -EPO is not holding the cold. As Bob Chill has been saying in the MA, we have gotten away w bad teleconnections during the past few winters. But generally, a ++AO/+NAO is not good for winter wx on the EC. Now, these two time periods modeled on the Weeklies are juicy...but will they have precip for the mid and southern valleys? It has been consistent in marking these two time frames. So, we have a shot at some winter wx. One good Miller A and nobody remembers the lack of tracking. I can agree that it may be the best long range model but I don't think that saying that means a ton. At best it may have decent verification at 500, although the Euro only verifies at 80 percent at 500 in 7 days Link to comment Share on other sites More sharing options...
John1122 Posted January 20, 2017 Author Share Posted January 20, 2017 00Z GFS looked a little better again with a potential gulf system in a week. Verbatim it's elevation driven but it's really close to something good. Mountains get blasted, Plateau gets a few inches. Lower elevations are mostly rain with temps in the upper 30s. 540 line is close and 850s are close to a snow event as well. Link to comment Share on other sites More sharing options...
John1122 Posted January 20, 2017 Author Share Posted January 20, 2017 Precip has slowly trended NW and this system has looked better and better with each run. You can see the elevation driven snow areas. Link to comment Share on other sites More sharing options...
BlunderStorm Posted January 20, 2017 Share Posted January 20, 2017 1 minute ago, John1122 said: 00Z GFS looked a little better again with a potential gulf system in a week. Verbatim it's elevation driven but it's really close to something good. Mountains get blasted, Plateau gets a few inches. Lower elevations are mostly rain with temps in the upper 30s. 540 line is close and 850s are close to a snow event as well. By far it is not perfect but at least it is definitely much closer in time and likely in the realm of possibilities. It's just refreshing to see a potential system within the time span of a week when being interpreted. Link to comment Share on other sites More sharing options...
John1122 Posted January 20, 2017 Author Share Posted January 20, 2017 After that system clipper/nw flow snows set up. Link to comment Share on other sites More sharing options...
BlunderStorm Posted January 20, 2017 Share Posted January 20, 2017 In all I saw 4 possibilities for snow in this run at least for those in areas above roughly 1500ft due to temperatures and the other event being NW flow along with 2 clipper systems which affect the lower valleys along with higher elevations later in the run. Will just have to see. Link to comment Share on other sites More sharing options...
John1122 Posted January 20, 2017 Author Share Posted January 20, 2017 Beyond 240 the GFS is still advertising multiple Eastern valley favorable track northern stream impulses. On that run there's snow showery weather nearly every day for a week straight in the region. Piles up 4-6+ on the Plateau and buries the mountains and SWVA with 12+. 1-3 elsewhere in most of the eastern valley. Link to comment Share on other sites More sharing options...
John1122 Posted January 20, 2017 Author Share Posted January 20, 2017 The 18z GFES had some really good potential for the entire valley on several members. Link to comment Share on other sites More sharing options...
Carvers Gap Posted January 20, 2017 Share Posted January 20, 2017 Yep, 6z GFS does have the threat John mentions. Hopefully we will see it get more support from the Euro/GEM as we get closer. Looks like folks at elevation need to be watching this one...or...the wave on the GFS gets stronger. The 6z GEFS, 0z EPS, and 0z GEM are in similar agreement about the long term look of the pattern. It has also been depicted on the Weeklies. The ridge slides under the trough after about seven days(from the beginning of when it gets cold)...The EPS control does provide some hope as is does provide repeating shots of cold air throughout its run. Link to comment Share on other sites More sharing options...
John1122 Posted January 20, 2017 Author Share Posted January 20, 2017 12z GFS continues to show the potential of the pattern with NW systems on parade. It lost the first miller A type system. These impulses will be hard to nail down on exact track and amount of moisture. Areas could see much more or much less than depicted here but this is a good general idea. Snow waves continue beyond this all the way to the end of the run. Link to comment Share on other sites More sharing options...
Met1985 Posted January 20, 2017 Share Posted January 20, 2017 9 minutes ago, John1122 said: 12z GFS continues to show the potential of the pattern with NW systems on parade. It lost the first miller A type system. These impulses will be hard to nail down on exact track and amount of moisture. Areas could see much more or much less than depicted here but this is a good general idea. Snow waves continue beyond this all the way to the end of the run. Yeah the 12z was another winner for a clipper parade. Link to comment Share on other sites More sharing options...
John1122 Posted January 20, 2017 Author Share Posted January 20, 2017 2 minutes ago, Met1985 said: Yeah the 12z was another winner for a clipper parade. It was a big winner in reloading some pretty nice cold too, not sure it can be trusted later on as usual, but it's a pattern that can bring huge snow totals to parts of Tennessee and Western NC/SWVA/EKY and puts people in the game from Nashville or so east for 1-3 inch type events. Link to comment Share on other sites More sharing options...
Met1985 Posted January 20, 2017 Share Posted January 20, 2017 9 minutes ago, John1122 said: It was a big winner in reloading some pretty nice cold too, not sure it can be trusted later on as usual, but it's a pattern that can bring huge snow totals to parts of Tennessee and Western NC/SWVA/EKY and puts people in the game from Nashville or so east for 1-3 inch type events. Yeah I agree. Usually with these events most places can squeeze out 3 to 6 inches at 3500 plus feet and 1 to 3 inches in the lower elevations. Yeah I liked the look of the 12z for reloading. Sometimes these northern streams can get juicy so who knows. Link to comment Share on other sites More sharing options...
BNAwx Posted January 20, 2017 Share Posted January 20, 2017 45 minutes ago, Met1985 said: Yeah I agree. Usually with these events most places can squeeze out 3 to 6 inches at 3500 plus feet and 1 to 3 inches in the lower elevations. Yeah I liked the look of the 12z for reloading. Sometimes these northern streams can get juicy so who knows. Yeah, even in Nashville, clippers can still put you in WWA territory. I remember living in Cookeville and in the mid 90's we had one "super clipper" that put down about 5 inches! Regarding the long range, I'm anxious to see if the strat warming will lead to any cold on our side of the globe. To me SSW's are always a crap shoot. Link to comment Share on other sites More sharing options...
John1122 Posted January 20, 2017 Author Share Posted January 20, 2017 18z bounces the first system back to the NW after the 12z had all precip staying south of the area. The exact track/strength will have major implications for elevated areas. Especially the eastern mountains, SWVA and far western NC. The NW tick means an extra 1-2 inches over the Plateau and an extra 2-4+ over the Eastern elevated area into extreme western NC areas next Thursday. Link to comment Share on other sites More sharing options...
Met1985 Posted January 20, 2017 Share Posted January 20, 2017 38 minutes ago, BNAwx said: Yeah, even in Nashville, clippers can still put you in WWA territory. I remember living in Cookeville and in the mid 90's we had one "super clipper" that put down about 5 inches! Regarding the long range, I'm anxious to see if the strat warming will lead to any cold on our side of the globe. To me SSW's are always a crap shoot. Yeah we can get some great little clippers that run through TN. lay down a quick couple of inches then out. Link to comment Share on other sites More sharing options...
John1122 Posted January 20, 2017 Author Share Posted January 20, 2017 18z with the first system being more robust. Link to comment Share on other sites More sharing options...
dwagner88 Posted January 21, 2017 Share Posted January 21, 2017 Just to voice an alternative opinion: I can't stand clippers. It gets cloudy and flurries. I have never seen more than a dusting from one. They are horrible snow producers in the southern valley. Link to comment Share on other sites More sharing options...
Carvers Gap Posted January 21, 2017 Share Posted January 21, 2017 31 minutes ago, dwagner88 said: Just to voice an alternative opinion: I can't stand clippers. It gets cloudy and flurries. I have never seen more than a dusting from one. They are horrible snow producers in the southern valley. Yep, dwag, you are correct. I was thinking about that very thing earlier today. Rare for Chatt to score on a clipper. The one thing(if I lived in the southern Valley) that would give me some hope is the amount of energy in the northern stream. Could some of that phase w energy coming out of the south? I am not saying that to give false hope... but there have been some near misses in the LR. The energy is just out of sync w the two streams(stove has to be thinking Ghostbusters meme here). I am pretty much to the point where any snow from this point forward is a bonus. What looked like a very promising pattern is now looking less so to me...Now, there is still about six weeks left of winter left...so plenty of room left for mischief. However, I think as we have seen all winter, it is growing unlikely that we see long stretches of cold weather from this point forward. Link to comment Share on other sites More sharing options...
John1122 Posted January 21, 2017 Author Share Posted January 21, 2017 1 hour ago, dwagner88 said: Just to voice an alternative opinion: I can't stand clippers. It gets cloudy and flurries. I have never seen more than a dusting from one. They are horrible snow producers in the southern valley. I was in Chattanooga for the super bowl a couple years ago and one laid down about 1.5 inches in Hixon. Dove down well west of the area. The 18z shows one diving down through West TN or Arkansas and giving snow to Mississippi, Alabama and Georgia. Link to comment Share on other sites More sharing options...
jaxjagman Posted January 21, 2017 Share Posted January 21, 2017 1 hour ago, John1122 said: I was in Chattanooga for the super bowl a couple years ago and one laid down about 1.5 inches in Hixon. Dove down well west of the area. The 18z shows one diving down through West TN or Arkansas and giving snow to Mississippi, Alabama and Georgia. That would be rare ,clippers in our area are never that deep to the south Link to comment Share on other sites More sharing options...
BlunderStorm Posted January 21, 2017 Share Posted January 21, 2017 GFS 00z, hour 234 total accumulated snowfall 10:1 ratio. A little less this time but still pretty good. Link to comment Share on other sites More sharing options...
JayCee Posted January 21, 2017 Share Posted January 21, 2017 11 hours ago, dwagner88 said: Just to voice an alternative opinion: I can't stand clippers. It gets cloudy and flurries. I have never seen more than a dusting from one. They are horrible snow producers in the southern valley. Yeah, the southern Plateau is not the friend of the southern Great Valley. The heaviest snow falls west and east of the Chattanooga area with moisture starved northern stream systems. Clippers are very hit and miss even here in the central Great Valley and foothills. Many times its strictly the Plateau and Mountains that get any measureable snow, and we get a heavy dusting to maybe an inch here. I seem to do slightly better than the western valley--west of Knoxville--mainly because that area gets downsloping off the Plateau, while over this way the cold air and moisture starts banking up against the high peaks of the Smokies and some redevelopment occurs. Even so, it takes a pretty strong clipper diving far enough south to get me excited. Link to comment Share on other sites More sharing options...
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