December Breakdown

With the AO/NAO forecast to be very negative in the long range it will be very difficult to see prolonged warmups across the east for the start of December. A 3-5 day warm spell will have an impact from the 1st to the 5th of december as the ridge in the plains moves eastwards.
The control is off the charts negative in both the AO and NAO shows by the blue line:

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8-16 day period notice the cold shifting to the west and impressive warmth shifting eastwards centred south of canada:

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A period from the 4th to the 8th of december looks like the time to watch for a trough in the east as we are seeing the east asian trough developing by 48 hours meaning we should look for a trough to develop 7-10 days later. A storm will probably form in this time frame as well in the eastern half of NA which is something to look out for.
500mb chart at hour 240 

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Strong storm developing across east asia matches up with an eastern canada storm in the dec 4-8th period:

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Looking out further another shot of cold air will move southeastwards into the east as a trough plows in from the NW where snowfall is running above normal. The pattern we are going into is one of a negative NAO/AO and -PNA with plenty of cold air available. The ridge in the bering straits will be a prominent feature allowing for more energy to dive in off the west coast. This will pump a ridge in the western u.s causing above normal temps across the southwestern u.s. A battle ground will set up further north will above normal precip across b.c and california. This ridge will allow for a trough to form in the great lakes with a transfer of very cold air from northern Bc the yukon and alaska southeastwards. 
These features will get stronger as we go on in time but i like the positioning. 

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To sum up my main points:
1) A big warmup is in store for the central and eastern parts of canada for the first 5 days of december
2) A very favourable pattern for cold and snow will set up between the 6th and 20th of december with a potential for storms to develop from the midwest to the east coast