http://www.wxguy.storm2k.org/temp/am_ir ... _60E_8.gif
http://www.wxguy.storm2k.org/temp/am_ir ... _60E_1.gif
http://www.wxguy.storm2k.org/temp/tm_order.gif
Once the wave gets east of the Dateline we should begin to see the jet break through across the pacific, developing an Aleutian low and forcing the Ridge (which right now is near 150 W) eastward to about 120 W ending the PNA positive. As this happens the trough will progress eastward out of the western US into the central US over the next week and into the east by the last two weeks of the month as the MJO reaches the central tropical PAC.
I don’t know why some think that a STRONG omega ridge near 150 W qualifies as a +PNA pattern b/c it does not. When one has the ridge in the position it is characteristic of a –EPO. As you can tell from the EPO verification; it has been averaging STRONGLY negative in response to that ridge.

And the PNA of course has been negative as well since the trough is along the west coast.

The majority of the data including the 12z GFS ensembles, Operational ECMWF out to D 10 and GGEM ensembles supports these changes.
http://www.meteo.psu.edu/~gadomski/ENSC ... z/f240.gif
http://wwwt.emc.ncep.noaa.gov/gmb/ens/t ... 10812.html
http://www.wxguy.storm2k.org/temp/ecmwf12zfri.bmp
What does it mean?
1) Storm track shifts eastward w/ time.
2) PNA goes positive and perhaps strongly so depending on the amplitude of the ridge.
3) MAJOR arctic outbreak possible Down the Plains into the EUS over the next week or two.
4) Increasing threat of a significant east coast event as the SE ridge is shoved eastward into the Atlantic.
5) AO/NAO trend downward at the very least.
6) PAC NW warms up and dries out.
Here are the ensemble forecasts for the NAO, PNA and AO over the next 15 days. BUT FIRST be aware of the fact that the GFS ensembles have been doing a poor job w/ these teleconnections for quite awhile.
http://www.cpc.ncep.noaa.gov/products/p ... .sprd2.gif
http://www.cpc.ncep.noaa.gov/products/p ... .sprd2.gif
http://www.cpc.ncep.noaa.gov/products/p ... .sprd2.gif
IF I lived in the PAC NW or in the west I would be enjoying the winter weather while its lasts b/c it’s coming to an end over the next two weeks. For the east, just hang in there the change is almost here.
Also of note, the warm pool is intensifying in the GOA and increasing in spatial coverage and were beginning to see the development of a cold/warm pool couplet from west to east across the NPAC basin. This is favorable for a mainly +PNA pattern and enhanced Aleutian low. Similar to--- but not yet to the extent of 1987, 1993, 2002.
http://weatheroffice.ec.gc.ca/data/sais ... _gl_sd.gif