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Roger Smith winter forecast -- mild mild cold


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I still like Feb 15-25 for the best winter storm potential for the northeast U.S. ... my method being statistical, there are no new statistics to consider, so I just go through a rather simple two-step process of making a forecast and then studying the errors to see what that could tell me about the theory behind the statistics. While eastern North America has worked out quite well, I have some problems to study across parts of the west.

If I just looked at it subjectively and took into account the ongoing discussions about stratospheric warming and related matters, I would say that February is most likely to play out as a more variable zonal type of month with some intervals of blocking that I would expect to be dominated by severe cold over Quebec and Labrador. There is a good snow pack up that way already in contrast to some other parts of subarctic Canada. Given a reasonable period of higher pressure in Greenland, we could see a much better set-up for winter storms developing at times in February.

Fingers crossed that it will begin to change, because at the moment the 16-day GFS shows mostly intervals of cold/dry separated by mild/wet that would average out somewhere around zero to +2 anomaly-wise to the end of January.

Anyway, from the "index values" that were generated for this forecast and after thinking about it again today, I would say expect maybe two or three decent snowfall events in February and one in March, from the pattern that is foreseen -- and a gradual rather than sudden arrival for spring, possibly a colder episode in April too.

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Very well done. Considering you put this out in October, I'm impressed. You're the only one that was able to see this pattern coming from that time period. Once the strong vortex regime became more evident by mid/late November, there were some later winter outlooks capitalizing on this knowledge and forecasting well. But you saw this coming from October so that deserves major kudos in my opinion. If February doesn't verify, it's still an excellent forecast. Getting 2/3 of the months correct, for the significant positive anomalies as well, is a well above avg long range forecast.

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The storm track consisted of storms moving across country and curving into Canada. We also had some big storms that formed with the cut-off energy in the Four-Corner region and progressed toward the East Coast (this includes October 29-30, January 11-12th). Yeah it is near or above average in temperatures but Roger is not right about the storm track being uneventful on the East Coast.

TNE

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The storm track consisted of storms moving across country and curving into Canada. We also had some big storms that formed with the cut-off energy in the Four-Corner region and progressed toward the East Coast (this includes October 29-30, December 11-12th). Yeah it is near or above average in temperatures but Roger is not right about the storm track being uneventful on the East Coast.

TNE

Disagree. Other than 2 or 3 rainstorms, the Dec 1-Jan 10 period has largely been tranquil, dry, and mild on the East Coast.

3exa8.png

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Historic east coast blizzard end of Jan first few days feb.... followed by severe artic cold most of feb... cold march april.

with something big poss early March... As for above I would go with Feb 2nd. (give a day or two)

Peace

I didn't know it could snow with temps near 70? :facepalm:

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The storm track consisted of storms moving across country and curving into Canada. We also had some big storms that formed with the cut-off energy in the Four-Corner region and progressed toward the East Coast (this includes October 29-30, January 11-12th). Yeah it is near or above average in temperatures but Roger is not right about the storm track being uneventful on the East Coast.

TNE

Disagree. Other than 2 or 3 rainstorms, the Dec 1-Jan 10 period has largely been tranquil, dry, and mild on the East Coast.

so it suggests the wait for big-time winter storms may require patience, but could eventually be rewarded,

by a developing strong storm track dropping south from a position through the Great Lakes in late January

to the east coast in February.

Not terribly different from 2010, I suppose ... which sounds good so ... patience !!!

One of the storm tracks has been "up the East Coast" throughout this winter. The most recent threat on January 11-12, and the most formidable event was with a further east track and with proper phasing with the polar jet on October 29-30th.

Usually this involves the cut-off energy that is in the tail-end of a frontal boundary. The cut-off energy usually organizes at the four corner region, and in cases this energy will phase with the polar jet that dives into the West. Just to prove that this pattern is repeating itself we look at the most current GFS:

NOTICE: Cut-off Energy sitting at the Four-Corner Region, Polar energy diving into the Country, Upper Trough Rebuilds:

post-7550-0-24903400-1326477770.gif

post-7550-0-34857800-1326477780.gif

The point is that the track is there, the cold air is lacking, but it does not mean we cannot get a repeat of Oct. 29 throughout this winter.

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im confused by the last line.. doesnt seem like 2010 at all. but otherwise, cool. overall, long range forecasting has been exposed again this winter.

It is a bit confusing, unless you're looking at the warm anomalies over eastern Canada.

That brought me back to re-read the forecast

Due to the nature of this forecast, I will make it very brief. The annual number crunch for my research method reveals a very mild pattern for the Great Lakes and northeast lasting through much of December and January, but a flip-flop to a very cold pattern by end of February into March. This seems a lot like 1967 as an analogue, so it suggests the wait for big-time winter storms may require patience, but could eventually be rewarded, by a developing strong storm track dropping south from a position through the Great Lakes in late January to the east coast in February.

The severe cold suggested for February will probably pool over central Canada and the north central states from late November to mid-January to fire up a storm track that will run something like KS-MN early in the season, MO-MI later in January, and eventually GA-seVA-NS by February, as the severe cold pool is drained out by deflation of a persistent east coast ridge in the first half of winter.

West coast may escape the direct influences of the western cold pool as a confluent jet stream near northern Vancouver Island drops southeast into the southern Rockies. This would favour heavy snowfalls in the interior parts of BC and southern Alberta, Montana, Idaho, Wyoming, northern/central Utah, and Colorado this winter. It may favour heavy rains on the west coast including much of California.

Up until now, neither of the bolded parts are correct. However, we should see some semblance of this pattern in the coming days, if only for a short period.

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The western region has been generally milder across western Canada with the tendency being towards frequent chinook warming over top of a cold Great Basin high. So instead of having the cold air confined to central Canada it has been more confined to regions near the Arctic Ocean, but as Ellinwood says, that will be adjusting more towards the scenario of the forecast in the next week or two. I think the conventional la Nina concept got into my thinking there, but the eastern forecast is based on index values for the regional climate so to some extent the forecast is a hybrid of those regional index values and conventional teleconnections.

I also have some trouble understanding the point being made about an "active" east coast storm track, by historic standards I would have to say there has been next to nothing going on all winter east of the Appalachians, and a rather anemic circulation through the Great Lakes too.

For validation of the research model I am mainly interested in the eastern regions, as well as a separate Europe-based forecast that has a research data base. Currently I don't have a western North America data base and tend to look for the best analogues from the eastern forecast set. I'm hoping to get that western data base on line this summer and perhaps it will improve the forecasts going forward, assuming that the Mayan long-range forecast proves incorrect (just a joke, I know they didn't really predict anything except the need for a new calendar).

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The western region has been generally milder across western Canada with the tendency being towards frequent chinook warming over top of a cold Great Basin high. So instead of having the cold air confined to central Canada it has been more confined to regions near the Arctic Ocean, but as Ellinwood says, that will be adjusting more towards the scenario of the forecast in the next week or two. I think the conventional la Nina concept got into my thinking there, but the eastern forecast is based on index values for the regional climate so to some extent the forecast is a hybrid of those regional index values and conventional teleconnections.

For validation of the research model I am mainly interested in the eastern regions, as well as a separate Europe-based forecast that has a research data base. Currently I don't have a western North America data base and tend to look for the best analogues from the eastern forecast set. I'm hoping to get that western data base on line this summer and perhaps it will improve the forecasts going forward, assuming that the Mayan long-range forecast proves incorrect (just a joke, I know they didn't really predict anything except the need for a new calendar).

You're still doing better than most of us :P Analogs have been failing big time, so it's no wonder the western areas didn't line up. Definitely a unique year.

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Still think its funny?

I thought the same thing and was gonna' post that until I saw your post

predicting wx is humbling

no one should ever dismiss any forecast out of hand because even when the forecast is not perfect, the forecaster still brings something to the table for consideration

this has been, all things considered, the best winter forecast so far that I've seen issued before NOV

you've made a lot of "well known" mets look pretty silly Roger (but that could always change next year!)

congrats!

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