Get ready for the great MW/GL storm of Dec 19-21

[Roger Smith]

Long-range signs are good for MW/GL storm Dec 19-21

_______________________________________________

This is one of my long-range speculative forecasts like the triple phaser episode from last winter. Okay, that turned into just the first of half a dozen mega-snowstorms for the east coast. In this case, I am fine tuning the LRF segment that talked about a storm at the December full moon (also northern max) to affect mainly the Midwest and Great Lakes region. With the storm being indicated for Dec 11-13 on a similar track and with large-scale features locking into a pattern that resembles the LRF for that time segment (after a somewhat cold start in the east), I am upgrading the LRF speculation to an early warning on a high probability major storm event for the Midwest and Great Lakes region in the time period Dec 19-21.

This storm could be expected to form around OK-KS late 18th and start moving northeast on the 19th, reaching Wisconsin on the 20th and central to northeast ON by the 21st. A track somewhat further south is still in play, and could run AR-IN-wNY. Whatever track this storm takes, there would likely be a heavy snowfall of 12-18 inches to the north, bands of freezing rain and rain along and just to the south of the track, and a brief but major warming spike in the warm sector ahead of the low.

There remains some chance of this strong disturbance taking an east coast track for an inland northeast snowstorm, but I think the odds favour the snow hitting a region from e KS and MO northeast across IA, w IL into WI and se MN. There could be a major arctic blast phasing in with this storm to bring blizzard conditions to the upper Midwest.

Will continue to update this thread with track and intensity ideas until it becomes part of the reliable model time frame, at which time I imagine it will become a hot topic in general on the forum.

About the time this storm crosses Lake Michigan, a strong Pacific storm will probably be bearing down on Vancouver Island and western WA with heavy rains, inland snow, and very strong winds. That storm will likely follow a similar track to the Dec 19-21 storm around Dec 23-25 but may not be as strong, so for that reason, I am predicting a snowy Christmas period for the Midwest and Great Lakes, and a mild Christmas on the east coast, although perhaps with one or two cold days between the two warmings. The coldest dates likely to be the 22nd-23rd between two spikes of warmth around 55-60 F.

[Ellinwood]

I promise not to troll if you have scientific reasoning behind this

Definitely a better start than Road Runner/WX1996, that's for sure.

[wxmeddler]

Euro's got your back for a storm. track is of course TBD.

[Kaner587]

Euro's got your back for a storm. track is of course TBD.

maybe but no low is cutting into that west based -NAO...screams secondary low formation off the east coast

[CAD_Wedge_NC]

maybe but no low is cutting into that west based -NAO...screams secondary low formation off the east coast

I have to agree......unless the block breaks down this is not going to happen.

[Chris L]

ECMWF has a huge west based -NAO, I doubt it cuts inland like the current one will do.

[Roger Smith]

Update on this storm concept ... the wave being shown on various models tracking near PHL east on Dec 17 is not likely to represent an early and southern solution to this energy peak. It is more likely to be the first signs of warm frontal wave development ahead of massive cyclogenesis likely to invade the west around that time (as suggested on today's 144h CMC - GEM global) that would rapidly transfer to a centre in Colorado around 18th-12z and seed the storm that was being discussed above. I wouldn't rule out a breakaway separate system around the 17th for a 4-8 inch snow event in the coastal northeast but this would not preclude stronger development around the 20th-21st across the region.

Factoring in some of the comments above and model trends, I am currently speculating the track of the major low would be closer to the AR-IN-wNY track than the MO-eIA-WI, but those would form the rough limits so possibly a track near STL-LAN-YQA would be the current research model estimate, so a lake cutter in essence but possibly quite a powerful storm for the central and upper Midwest and a rapid temperature spike further south with severe weather potential across the south central, southeast and MA as the cold front comes through late 20th into 21st. (19th-20th for south central).

This is beginning to look like a winter for the ages to me, the La Nina is not the only player in this orchestra. The spectacular cold in Europe and the deep cold already evident in central Canada are entering battleground scenarios in many regions of interest here and in Europe, and we could really have our hands full with active storms this winter.

And I should add, there is probably at least a 25% chance of this energy peak (Dec 20-21) erupting into a coastal snowstorm despite my prognosis above, because I certainly buy into the suppressed heights comments and feel that only the strength of the disturbance and some limited retrogression in the Quebec sector will prevent this from going coastal. But at present, feel that Chicago is ground zero for this energy peak to deliver a heavy snowfall event.

[Ellinwood]

What support, besides looking at a couple models, do you have for this?

[Roger Smith]

Forecast is based on research into weather-geomagnetic and lunar energy and index values from data sets, applied to a grid that I have developed for timing storms. This has met with some positive reviews on the forum (as historically defined) but I'm unable to retrieve much of the preceding material that includes discussions and comments. There was a research thread on EasternUS giving the scientific rationale. I hope to retrieve that and/or recreate it on this forum.

Basically, I posted this thread to add a bit of interest to the weather forum at what seemed like a somewhat slow time, but also, it's consistent with my LRF details that are in the LRF thread (last updated Nov 8 so it's back around page four of this forum now). Just noting that the two storms now on the map in Iowa and WA state are well handled by the research model as per the LRF. The LRF lists a number of other specific predictions -- the basic idea is that the timing of energy peaks is blended with the anticipated flow pattern (and that could be from any blend of research and conventional factors) to give storm tracks and then conventional meteorology/climatology is used to give impacts. This is probably similar to what half a dozen other forum members are doing independently with their own research data bases and concepts. I believe there would be some overlap and some independent features in various theories.

Having a lot of success with the methodology this year and made an accurate summer forecast with it, as well as a good start to the European winter forecast published on net-weather and the Irish forum boards.ie/weather.

Just like any other developing theory, following the data and the trend of results. This particular forecast blends a strong postulated energy peak at 08z Dec 21 with index values showing average locations of resultant low pressure in analogue situations, and then factoring in known evolutions at present. At the time of issuance, had not consulted ECM or GFS and as the LRF was first issed in September, clearly this is a black box type method.

[Guest someguy]

this is total BS

the MOON? really????

what about when the gravitational Pull of Jupiter affects Ur anus?

Long-range signs are good for MW/GL storm Dec 19-21

_______________________________________________

This is one of my long-range speculative forecasts like the triple phaser episode from last winter. Okay, that turned into just the first of half a dozen mega-snowstorms for the east coast. In this case, I am fine tuning the LRF segment that talked about a storm at the December full moon (also northern max) to affect mainly the Midwest and Great Lakes region. With the storm being indicated for Dec 11-13 on a similar track and with large-scale features locking into a pattern that resembles the LRF for that time segment (after a somewhat cold start in the east), I am upgrading the LRF speculation to an early warning on a high probability major storm event for the Midwest and Great Lakes region in the time period Dec 19-21.

This storm could be expected to form around OK-KS late 18th and start moving northeast on the 19th, reaching Wisconsin on the 20th and central to northeast ON by the 21st. A track somewhat further south is still in play, and could run AR-IN-wNY. Whatever track this storm takes, there would likely be a heavy snowfall of 12-18 inches to the north, bands of freezing rain and rain along and just to the south of the track, and a brief but major warming spike in the warm sector ahead of the low.

There remains some chance of this strong disturbance taking an east coast track for an inland northeast snowstorm, but I think the odds favour the snow hitting a region from e KS and MO northeast across IA, w IL into WI and se MN. There could be a major arctic blast phasing in with this storm to bring blizzard conditions to the upper Midwest.

Will continue to update this thread with track and intensity ideas until it becomes part of the reliable model time frame, at which time I imagine it will become a hot topic in general on the forum.

About the time this storm crosses Lake Michigan, a strong Pacific storm will probably be bearing down on Vancouver Island and western WA with heavy rains, inland snow, and very strong winds. That storm will likely follow a similar track to the Dec 19-21 storm around Dec 23-25 but may not be as strong, so for that reason, I am predicting a snowy Christmas period for the Midwest and Great Lakes, and a mild Christmas on the east coast, although perhaps with one or two cold days between the two warmings. The coldest dates likely to be the 22nd-23rd between two spikes of warmth around 55-60 F.

[Roger Smith]

DT? (same lame and irrelevant joke as in 2008)

Anyway, not everyone's a fan, I get it. Life's too short.

[Ellinwood]

Thanks for posting your methodology, no matter how outlandish it seems. I won't go after your methodology since I haven't seen the verifications of your forecasts yet. I would have thought that you would have saved the Eastern threads in the 2 weeks you had to do it, since it appears that Eastern was the only place you stored all of the information related to your theoretical forecasting. Such important data and verification should not be put on something that is not in your control.

Also, from reading your latest forecast, it looks like you pick out 3 different possible system tracks...

I am currently speculating the track of the major low would be closer to the AR-IN-wNY track than the MO-eIA-WI, but those would form the rough limits

And I should add, there is probably at least a 25% chance of this energy peak (Dec 20-21) erupting into a coastal snowstorm despite my prognosis above

It seems like you're making it pretty easy to verify your forecast if you never stick it to one type of system.

Granted, you did note your most favorable track:

a track near STL-LAN-YQA... so a lake cutter in essence but possibly quite a powerful storm for the central and upper Midwest and a rapid temperature spike further south with severe weather potential across the south central, southeast and MA as the cold front comes through late 20th into 21st. (19th-20th for south central).

Will this storm bust if it doesn't take this track once verification is done, or will you just say "I said it could be this other track and it verified so my forecast verified?"

[Feb]

this is total BS

the MOON? really????

what about when the gravitational Pull of Jupiter affects Ur anus?

[Roger Smith]

No worries about the stuff on Eastern, it is replicated elsewhere. I was referring to some threads with forecasts for last winter's storms and various comments. But the research itself and all the data are stored here and I haven't lost anything of value -- since 95% of this forum seems to be the core of the Eastern forum, I didn't think I would have to go through this introductory stuff again. I'm sure some people remember the discussion of the Jan 30 triple phaser opportunity and how that played out as the first major snowstorm in the series that hit the MA.

The current model suppress this energy peak and develop very little in the time frame and the region discussed in this forecast. That just makes this more interesting, I suppose. With about a week to ten days left for development, this should turn into a good test of the research model. I would say, watch the region between AR and IN for enhanced development on a larger scale than anything suggested on the current models in the time frame Dec 19-20.

By the way, the comments about "the Moon -- really -- gravitational pull" seem rather daft to me, as the lunar component of ocean tidal variations is dominant over the solar component. What seems to have happened is that research into lunar-atmospheric interactions derailed before the modern age of meteorology because of some faulty assumptions about process, and how to visualize the interaction -- it is not a daily tide but a monthly harmonic resonance projected onto a grid like an interference pattern. The ocean has shorelines but the atmosphere has no such "boundaries" so the lunar energy that impacts the oceans and hits shorelines, is able to freely travel throughout the atmosphere -- however, it appears to do so in patterns that create timing lines for tidal effects (low pressure systems and fronts) and therefore to find the lunar effects, you have to study particular points and not the entire atmosphere. Of course there is no "lunar effect" on the entire atmosphere at any given time, but there is a demonstrable effect at timing lines. This is so obvious when you get into the research that I am very surprised that people who solved more complex scientific questions failed to recognize it. But all anyone here would need to do is number crunch 100 years of Chicago, Detroit or any other regional weather data and I'm sure you would see these effects, just use the sidereal 27.32166d rather than the full moon / new moon 29.53d periodicity, because the key events are sidereal. I mention those locations because a timing line runs through the region (approximately DLH-MSN-ORD-CHS) and even at the distance of Toronto, my base for 170 years of data, the effects are easily demonstrated with a predictable lag of about 9h.

Jupiter and other planets might play a role in the solar system magnetic field component of the theory but have nothing to do with these interference patterns. So that would be a separate discussion about long-term harmonics in background temperature trends. All of those can be demonstrated in a long series of data, once again, if anyone took the time and trouble to develop a 398.9 day temperature series this would demonstrate a series of waves that I have found in various locations' temperature data showing a second-order variation of about 0.7 C deg -- and there are a number of other similar signals -- showing that atmospheric variability may be related to predictable changes in the solar system magnetic field, which after all is the outer portion of the geomagnetic field, which again is the outer portion of our atmosphere.

When you think about it, the atmosphere is obviously related to the magnetic field -- the timing of events, the flow of electrical energy, and the shaping are all related. In the past two centuries, the arctic vortex has followed the drift of the NMP and when you start talking about the importance of patterns at heights like 10 mbs, you are really talking about the interface between atmosphere and geomagnetic field. So I don't feel that this line of research is anywhere near as "wacky" as some operational mets seem to think, and I'm sure it will be seen as mainstream before much longer, the way the results are going. In 2009-10, in a freely conducted poll on the UK Netweather forum, almost half the respondents chose our forecast (made in collaboration with my research associate in the UK) for winter 2009-10 as being the best of over two dozen published on the forum. Things are looking quite good for this winter's forecast also. Last year's summer forecast for the US published on Eastern was quite accurate. Obviously, with successful results like these, I am going to keep developing the research as long as I can, and I hope that it will become more mainstream. Publication is extraordinarily difficult because of the length and complexity of documentation, as well as cultural taboos and intellectual rigidity. Obviously I cannot simultaneously do thirty years of maverick research and create a conventional persona in the profession. But many obvious things are not obvious in the atmospheric sciences profession (as we see daily in the debates over global warming).

But if people have a hankering to take on outlandish ideas, you might look in that direction, because unlike the AGW lobby, I am not proposing to tax you while proving my theory, nor will I lay down a dense carpet of wind turbine grids in your back yards to produce energy at roughly 1% the cost efficiency of already-proven technologies. So you know, who really is the wacko here?

[Ellinwood]

No worries about the stuff on Eastern, it is replicated elsewhere. I was referring to some threads with forecasts for last winter's storms and various comments. But the research itself and all the data are stored here and I haven't lost anything of value -- since 95% of this forum seems to be the core of the Eastern forum, I didn't think I would have to go through this introductory stuff again. I'm sure some people remember the discussion of the Jan 30 triple phaser opportunity and how that played out as the first major snowstorm in the series that hit the MA.

The current model suppress this energy peak and develop very little in the time frame and the region discussed in this forecast. That just makes this more interesting, I suppose. With about a week to ten days left for development, this should turn into a good test of the research model. I would say, watch the region between AR and IN for enhanced development on a larger scale than anything suggested on the current models in the time frame Dec 19-20.

Thanks for clarifying the data issue... glad to hear you still have it. I can't say I saw your work, since I avoided any sort of winter threads up until this season. I won't bother to ask you to post all of that again, though, if I'm only one of a few that haven't seen it before and are interested. I would say that, given how the models handled this most recent system in the 7-10 day time frame, the track you describe isn't that far-fetched.

[Roger Smith]

The range of tracks relates to how this research can be applied in the super-long-range. Granted we are now 7-10 days away and approaching the reliable model time frame (where similar track ranges are often in play).

Track in theoretical terms is determined by the interaction of the energy level of the storm (signal strength) and the large-scale atmospheric waves expected at forecast time. What I see in the research is a strong signal interacting with a somewhat suppressed zonal flow, with retrogression underway, and this suggests a track pushing northeast from the southern plains towards the central Great Lakes.

As we are getting closer to the time frame I have the impression that a more southerly track will verify. But the research validation is not based on "yes/no" type statistics but on degree of correlation. A storm track from the eastern Gulf up the east coast would be a poor fit to the research track but not to the timing component or the energy level component. It would point to the flaw being in the large-scale setup forecast which is independent of lunar orbital variables.

There are occasionally misfires in this research model, I have already stated that in earlier discussions and given that I am just trying to extend what we can already do beyond the end of the 10-16 day GFS time window, I suppose it is reasonable to have a fairly flexible concept of validation for this, if we can just start to see the general pattern and have a better than random total series of forecasts from the methodology, then this is lifting up the extended portion of the performance curve that has so many other ongoing developmental changes in modern meteorology. And overall, I think this method is succeeding in doing what it sets out to do, but as anyone familiar with the variability of the models in the day 6 to 10 time frame will realize, improvements over random will involve a large amount of potential error. Anyway, I've had my chance to vent and rant, so would suggest just waiting to mid-week to see how things are actually evolving. The key thing for the research will be to locate and then track the energy that represents the full moon / northern max event on each of nine timing lines around the hemisphere. Note from the above discussion that timing lines are curved and run approximately NNW-SSE at high latitudes then more NW-SE as they reach the mid-latitudes. This means that a suppressed storm will be further east in the timing system than a storm in the average jet stream position.

[Ellinwood]

Anyway, I've had my chance to vent and rant, so would suggest just waiting to mid-week to see how things are actually evolving.

That's the most reasonable thing I've heard on this forum since the winter threads started. I share your sentiments.

While I agree that finding the more favorable tracks in the long-term is better than nothing, I don't think it has much practical use in forecasting at this point and time. From a weather risk perspective, you're either looking at a potentially big event for the Great Lakes or a potentially big event for the East Coast, which doesn't do much to help people prepare for a significant event.

[Yeoman]

this is total BS

the MOON? really????

what about when the gravitational Pull of Jupiter affects Ur anus?

[Roger Smith]

Well, I was just over in OT, and I see that in terms of pattern recognition, I got one right already. (LOL)

Let's hope the weather follows suit.

Off topic, but there are some stunning maps over the Atlantic and Europe next few days. Looks a bit like the infamous winter of 1962-63.

[Ji]

Well, I was just over in OT, and I see that in terms of pattern recognition, I got one right already. (LOL)

Let's hope the weather follows suit.

Off topic, but there are some stunning maps over the Atlantic and Europe next few days. Looks a bit like the infamous winter of 1962-63.

is this MW/GL storm still on the table or is it now an EC storm?

[Roger Smith]

Well so far, on models I've checked, this has gone from being an early misfire to a non-event to a powerful southeast coastal and ... so let's wait a day or two and see what the models cough up next. I've seen this happen with postulated storms in the past, that the models showed all these different solutions, then backed off the strength of the pattern, allowed more zonal flow, and then you suddenly get the cyclogenesis showing up on land and heading for the lower Great Lakes.

I may have picked a high wire act on this event with the Greenland blocking high so strong, but right now, the northern hemisphere is about to get rocked by sudden pattern changes. I can't see it staying as mild as it is on the west coast past about the 18th, but the western warmth may spread into the high plains. If the suppression of the downstream blocking fades, then some of these GFS offshore storms may start to show up further northwest. In my research model, events that move north also move northwest so they seem "later" if you're fixed on the north-south east-west grid. What I mean is, if you're considering a model forecast storm near Hatteras at day five but you suspect it may cut further north, the place to move it is Ohio, not western New York, to preserve the model timing on curved timing lines.

Anyway, this should be a very interesting period with the almost unprecedented strength of the Greenland high, a polar vortex dropping south towards Britain from Svalbard (Spitsbergen) and rather flabby features over North America, a retrograde chain of events could see an attempt at modest ridge building over the southeast, trough development west coast, and a storm track setting up inland northeast. I realize the models are not showing much of that today, but we are talking about a week from now and the way these models have been handling the past two weeks, a lot could happen unexpectedly. So I think the most plausible track for the storm given the current evolution and uncertainty might be south of what I said earlier but not that much so, possibly LA-TN-PA-NY. Is that what you call an Apps runner rather than a lake cutter? This GFS tendency to offshore bombogenesis just looks suspicious to me given the developments upstream. I forecast daily in Ireland and the UK, and we've been seeing a lot of problems with the GFS over the Atlantic in the day 5-8 time frame, basically, it keeps wanting to develop storms too far north and bring them across the British Isles, but they head for Spain and the Med instead.

I hope the full extent of my confusion has been communicated here.

???

[buckeye]

Well so far, on models I've checked, this has gone from being an early misfire to a non-event to a powerful southeast coastal and ... so let's wait a day or two and see what the models cough up next. I've seen this happen with postulated storms in the past, that the models showed all these different solutions, then backed off the strength of the pattern, allowed more zonal flow, and then you suddenly get the cyclogenesis showing up on land and heading for the lower Great Lakes.

I may have picked a high wire act on this event with the Greenland blocking high so strong, but right now, the northern hemisphere is about to get rocked by sudden pattern changes. I can't see it staying as mild as it is on the west coast past about the 18th, but the western warmth may spread into the high plains. If the suppression of the downstream blocking fades, then some of these GFS offshore storms may start to show up further northwest. In my research model, events that move north also move northwest so they seem "later" if you're fixed on the north-south east-west grid. What I mean is, if you're considering a model forecast storm near Hatteras at day five but you suspect it may cut further north, the place to move it is Ohio, not western New York, to preserve the model timing on curved timing lines.

Anyway, this should be a very interesting period with the almost unprecedented strength of the Greenland high, a polar vortex dropping south towards Britain from Svalbard (Spitsbergen) and rather flabby features over North America, a retrograde chain of events could see an attempt at modest ridge building over the southeast, trough development west coast, and a storm track setting up inland northeast. I realize the models are not showing much of that today, but we are talking about a week from now and the way these models have been handling the past two weeks, a lot could happen unexpectedly. So I think the most plausible track for the storm given the current evolution and uncertainty might be south of what I said earlier but not that much so, possibly LA-TN-PA-NY. Is that what you call an Apps runner rather than a lake cutter? This GFS tendency to offshore bombogenesis just looks suspicious to me given the developments upstream. I forecast daily in Ireland and the UK, and we've been seeing a lot of problems with the GFS over the Atlantic in the day 5-8 time frame, basically, it keeps wanting to develop storms too far north and bring them across the British Isles, but they head for Spain and the Med instead.

I hope the full extent of my confusion has been communicated here.

???

M-O-O-N....that spells app runner

[NEOH]

Roger - Any change to your thoughts about this storm?

[buckeye]

Roger - Any change to your thoughts about this storm?

was wondering the same thing....looks like there may be about 1000mile error west in the lunar-generated forecast modelling.

[Roger Smith]

I see so much spread on the models that we can safely say this is a complex evolution underway with the GEM showing closer correlation to my research model than GFS or Euro.

Research model would require wave or low on timing lines at 08z Tues Dec 21. Timing line one as used in the model runs approx DLH-ORD-CHS. Two other timing lines in play are approx 40 deg east and west of that. Past 15 days have seen stronger development of waves near timing line 2 (east of timing line 1). Theory also allows for east-west oscillation of timing lines and forecast model for season was based on slow westward drift of all N American timing lines but estimated position for Dec 21 only slightly east of equilibrium, say 100 miles so that only makes about a 3h "early" adjustment to model positions.

Model also calls for retrogression with WNW component across arctic at this time. This is well verified especially with the European forecast which can be read on the Net-weather site under my name and "Blast from the Past" (a collaborating researcher in U.K.) ... our 2009-10 winter forecast was voted best of forum, and we're getting good reviews so far in this extremely cold winter. The recent developments in Greenland fit the model very well. The blocking should expand west but pick up further reinforcement from retrograde Siberian highs through Scandinavia later this month and in January. So we believe that the blocking will stay in place but create a stronger arctic vortex over northern Hudson Bay eventually as heights try to build over the GL in response to field warming over the sector and the NW component of retrogression. That process in theory was to be in early stages during development of this Dec 21 event and much more advanced by the next two major events on Dec 28 and Jan 3-4.

What this means in plain forecasting terms is that there should now be a tendency for the flow to return to a more zonal appearance over central-eastern NA and for high energy peaks to have more success in pushing into the arctic air. Even though we are now at 138h to energy peak, model consensus is so poor that I fell our research model has as much chance as any model of verifying, but my approach has always been to taper the forecasts to model consensus as time ticks down to event time, and the model consensus suggests an Apps runner to me, even if no model shows that solution. So at this stage I have adjusted the theoretical track to SHV-BNA-CRW-SYR with the 12z Dec 21 position likely to be eastern KY. This seems like a good track for 6-12 inches of snow in parts of the Midwest and lower Great Lakes, with east wind squall enhancement zones. Seems also like a mixed event for inland northeast and slight warming spikes on the coast ahead of the wave.

Will update daily from now on. As much as anything else, it's a question of which of the major models will resolve this puzzle first. The current GEM stays well north with wave development and has a sort of modified clipper evolution from a moderately strong central plains low to a Great Lakes trough. The GFS is obviously on steroids for offshore development and the last Euro I saw (00z) seemed to want to make minor developments in a hangback trough from a much weaker offshore.

Observers should note that storms well to the west of the forecast zone at event time are on upstream timing lines and are not displaced timing line one storms. The system uses nine timing lines and timing lines 8 and 9 are (8) in the eastern Pacific curving towards CA, and (9) on land near the west coast running somewhat further inland OR-ID then towards NM-sTX. The research indicates that alternate timing lines tend to have strong activity, so that with a strong Great Lakes low timing line 9 is usually at lower energy and the next major storm upstream would be near timing line 8 at that time. However, the theory also provides for a greater eastward shift of these timing lines as not all components in the system are displaced equally (there is a rippling effect westward in retrograde episodes and upstream timing lines are displaced east, downstream lines to their west). With that in mind, Dec 21 08z energy peak for timing line 8 should be near 100-200 miles west of the WA coast. The event for timing line 9 should be in e NM or nw TX with an arctic stream reflection near Great Slave Lake.

I expect the models to come into much better agreement by this time tomorrow. Watch for the GFS to start backing off from its offshore developments. The GEM may be the model currently closest to the right solution.

[psuhoffman]

What storm are you talking about on the 21st? There is a storm on the 19th and then nothing after that until at least the 23rd except perhaps a clipper or two or a very weak wave in the STJ riding under whatever has blown up into the candian maritimes from the Dec 19th storm. Are you talking about the track of the Dec 19th storm now shown by models as being OTS as an apps runner or are you talking about one of these minor waves or clippers around the 21st?

I see so much spread on the models that we can safely say this is a complex evolution underway with the GEM showing closer correlation to my research model than GFS or Euro.

Research model would require wave or low on timing lines at 08z Tues Dec 21. Timing line one as used in the model runs approx DLH-ORD-CHS. Two other timing lines in play are approx 40 deg east and west of that. Past 15 days have seen stronger development of waves near timing line 2 (east of timing line 1). Theory also allows for east-west oscillation of timing lines and forecast model for season was based on slow westward drift of all N American timing lines but estimated position for Dec 21 only slightly east of equilibrium, say 100 miles so that only makes about a 3h "early" adjustment to model positions.

Model also calls for retrogression with WNW component across arctic at this time. This is well verified especially with the European forecast which can be read on the Net-weather site under my name and "Blast from the Past" (a collaborating researcher in U.K.) ... our 2009-10 winter forecast was voted best of forum, and we're getting good reviews so far in this extremely cold winter. The recent developments in Greenland fit the model very well. The blocking should expand west but pick up further reinforcement from retrograde Siberian highs through Scandinavia later this month and in January. So we believe that the blocking will stay in place but create a stronger arctic vortex over northern Hudson Bay eventually as heights try to build over the GL in response to field warming over the sector and the NW component of retrogression. That process in theory was to be in early stages during development of this Dec 21 event and much more advanced by the next two major events on Dec 28 and Jan 3-4.

What this means in plain forecasting terms is that there should now be a tendency for the flow to return to a more zonal appearance over central-eastern NA and for high energy peaks to have more success in pushing into the arctic air. Even though we are now at 138h to energy peak, model consensus is so poor that I fell our research model has as much chance as any model of verifying, but my approach has always been to taper the forecasts to model consensus as time ticks down to event time, and the model consensus suggests an Apps runner to me, even if no model shows that solution. So at this stage I have adjusted the theoretical track to SHV-BNA-CRW-SYR with the 12z Dec 21 position likely to be eastern KY. This seems like a good track for 6-12 inches of snow in parts of the Midwest and lower Great Lakes, with east wind squall enhancement zones. Seems also like a mixed event for inland northeast and slight warming spikes on the coast ahead of the wave.

Will update daily from now on. As much as anything else, it's a question of which of the major models will resolve this puzzle first. The current GEM stays well north with wave development and has a sort of modified clipper evolution from a moderately strong central plains low to a Great Lakes trough. The GFS is obviously on steroids for offshore development and the last Euro I saw (00z) seemed to want to make minor developments in a hangback trough from a much weaker offshore.

Observers should note that storms well to the west of the forecast zone at event time are on upstream timing lines and are not displaced timing line one storms. The system uses nine timing lines and timing lines 8 and 9 are (8) in the eastern Pacific curving towards CA, and (9) on land near the west coast running somewhat further inland OR-ID then towards NM-sTX. The research indicates that alternate timing lines tend to have strong activity, so that with a strong Great Lakes low timing line 9 is usually at lower energy and the next major storm upstream would be near timing line 8 at that time. However, the theory also provides for a greater eastward shift of these timing lines as not all components in the system are displaced equally (there is a rippling effect westward in retrograde episodes and upstream timing lines are displaced east, downstream lines to their west). With that in mind, Dec 21 08z energy peak for timing line 8 should be near 100-200 miles west of the WA coast. The event for timing line 9 should be in e NM or nw TX with an arctic stream reflection near Great Slave Lake.

I expect the models to come into much better agreement by this time tomorrow. Watch for the GFS to start backing off from its offshore developments. The GEM may be the model currently closest to the right solution.

[Yeoman]

was wondering the same thing....looks like there may be about 1000mile error west in the lunar-generated forecast modelling.

I just pulled up captain's log and it appears previously unidentified forces from the Delta Quadrant may be affecting the trajectory of this great lakes monster. Completely understandable.

[Kevin Druff]

A bunch of stuff I only partially understood...

So, you're claiming that no model has the right solution 4 days out from the system. Further, the closest model is off by ~350 to 400 miles and the farthest by 1,000+?

[NEOH]

I see so much spread on the models that we can safely say this is a complex evolution underway with the GEM showing closer correlation to my research model than GFS or Euro.

So at this stage I have adjusted the theoretical track to SHV-BNA-CRW-SYR with the 12z Dec 21 position likely to be eastern KY. This seems like a good track for 6-12 inches of snow in parts of the Midwest and lower Great Lakes, with east wind squall enhancement zones. Seems also like a mixed event for inland northeast and slight warming spikes on the coast ahead of the wave.

I expect the models to come into much better agreement by this time tomorrow. Watch for the GFS to start backing off from its offshore developments. The GEM may be the model currently closest to the right solution.

Thanks, Roger. Appreciate the update. Sounds like your favored track hasn't changed. Will be interesting to see if the models come around to a solution more similar to yours. Obviously there are huge differences at this point.

I'm sure folks west of the apps will be interested in future updates as this is an ideal storm track for heavy OH valley snows.

[Ellinwood]

Research model would require wave or low on timing lines at 08z Tues Dec 21. Timing line one as used in the model runs approx DLH-ORD-CHS. Two other timing lines in play are approx 40 deg east and west of that. Past 15 days have seen stronger development of waves near timing line 2 (east of timing line 1). Theory also allows for east-west oscillation of timing lines and forecast model for season was based on slow westward drift of all N American timing lines but estimated position for Dec 21 only slightly east of equilibrium, say 100 miles so that only makes about a 3h "early" adjustment to model positions.

...

That process in theory was to be in early stages during development of this Dec 21 event and much more advanced by the next two major events on Dec 28 and Jan 3-4.

...

I have adjusted the theoretical track to SHV-BNA-CRW-SYR with the 12z Dec 21 position likely to be eastern KY.

Your post was a bit convoluted to say the least...

Here's your OP:

This storm could be expected to form around OK-KS late 18th and start moving northeast on the 19th, reaching Wisconsin on the 20th and central to northeast ON by the 21st. A track somewhat further south is still in play, and could run AR-IN-wNY. Whatever track this storm takes, there would likely be a heavy snowfall of 12-18 inches to the north, bands of freezing rain and rain along and just to the south of the track, and a brief but major warming spike in the warm sector ahead of the low.

So did your storm magically get moved back 3 days, or are you just looking at the next threat and completely disregarding your OP call? Sure, you said Dec. 19-21, but that was the time frame of the storm you suggested, not a window of possible initiation time.

EDIT:

And if you're still talking about this coastal/OTS storm becoming an app runner... good. luck. You'll need all you can get and more.