It is very, very early, but those early signs show the potential for a major pattern shift sometime around January 15th. This could lead to cold, snow, and ice around the middle to late January.
Both the AO (Arctic Oscillation) and NAO (North Atlantic Oscillation) are expected to flip from positive to negative phase. This will allow the polar jet stream to dive south into the middle of the country it will also create a trough over the eastern part of the country. This is a much more favorable pattern for winter weather and being in a La Nina pattern, over running and the potential for ice will have to be watched as well. Again it is very early, but for all of the winter lover fans, there are some signs of change in the new year.
Ross Ellet
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will it be a big one ?
All I can say is it’s about time. You know something is wrong when there’s a story on the news about people ringing in the New Year by camping out at Devil’s Den.
Been posting on my Facebook for a while regarding the SSW (which appears to be reloading itself in a few days), as well as the expected cold — I’m currently estimating an arrival of mid-January as the cold blossoms out and takes hold in the lower 48 starting in the Pacific NW and trending south and east with time. Feeling ice storm potential during this time is very high and ironically close to the 2009 ice storm in terms of setup. See PSU E-wall’s site for a reanalysis of the January 26-28 Ice Storm in NWA. GFS Ensembles show tanking AO and a PNA . . . the -PNA favors a trough out west. During 2009, the AO had just gone negative on the 23rd . . .as had the PNA. January is ideal for this set up because the days are still short enough for cold air to have momentum as it’s driving in, even without ample snow cover to the north. Not saying an ice storm of epic proportions will occur, but it’s a pattern conducive for one for sure.
Correction on my part — the AO was positive during that time — looking at the wrong Index Page. Which intrigues me more — we were able to get cold air to come in — can’t imagine what would happen with a negative AO involved.