Clues to the weekly December weather pattern

Positive phases of the NAO and AO over the next two weeks argue for milder conditions across much of southern Canada and the Lower 48 states. However, there are indications that the MJO may go into region 7 by the second week of December, which would argue for much colder air to get into the Prairies and the northern Plains of the United States by the third or fourth week of December, so the second half of December may look a lot different than the first half of the month.

Unfortunately, the pattern still looks wet into southern BC and the Pacific Northwest into the second week of December before the storm track may shift farther south, leading to less precipitation.