00z Jan 19th GEFS
Above normal 500mb heights return on the 22nd thru the 24th preceding the next system. On the 25th when below normal heights return (been consistent for a week). We still have an Aleutian trof, eastern Pacific ridging, eastern NOAM troffing, -NAO and Hudson Bay TPV outlooked. Angle of the coldest looks west of us. This is pretty much the same story through its run (NAO may become more negative, well anyway outlooked). But starting about February 1st, the Pacific flow looks more zonal even with our heights still below normal. the above normal SE heights are gone. Our heights return to near normal at the very end on February 3rd. If the GEFS bias is consistent, this is probably a week too fast at flattening the Pacific. We will follow the can.
NAEFS for the week of 1/27-2/3 is finally confident of below normal temps here.
00z Jan 21st GEFS
Above normal heights return on the 22nd thru the 24th preceding the next system. On the 25th when below normal heights return. Can see the double barrel energy in the troffing and the early next week system with a neg tilt look to it. On the 28th the NAO (as an index) looks positive, there is an Eastern Pacific Ridge and the PV in Hudson Bay not as great looking as earlier. Rest of January pattern is retrogressing (ridging thru Alaska on the 31st) as above normal heights return to our area. Angle of cold outlooked farther west. This is faster than two days ago. As February starts, the flow over the Pacific becomes more zonal, tight atypical nino pattern with below normal heights in Canada and above normal heights southern conus. 3rd thru the 5th our heights are near normal. South of Alaska troffing is outlooked at end of the run.
NAEFS for the week of 1/29-2/5 is confident of below normal temps starting just north & west of the Philly metro area westward thru the Northern Plains.
00z Jan 23rd GEFS
Current above normal 500mb heights are replaced by below normal heights on the 25th. This persists thru the 30th, although the > of the cold gets farther west as a northwest Atlantic ridge tries to retrograde west. Above normal heights eke to the west into our area as February starts. This is a day later than two days ago. On February 1st, we see a closed ridge over the Bering Sea; a zonal looking ridge/trof/ridge pattern across the conus. The EPO looks weakly positive, the nao is negative and a weaker TPV over northern Hudson Bay. Our 500mb heights are near normal until the 4th (below) by product of a cold shot. The Pacific does not look cold with ridging in the Aleutians and troffing across the eastern Pacific. Above normal heights (yeah la la la la la land) envelope most of NOAM at the end of the run on the 6th and 7th.
Personally though I can see this happening as a reboot or change given this is about the 3 week mark of the SSW vs what the GEFS was previously pushing about this occurring a week earlier. Granted by then the MJO could be in colder phases and thus negate it altogether.
NAEFS for the week of 1/31-2/7 is slight confident of below normal temps in our area, guessing cold weighted to the start of the week now that the GEFS has chilled.
00z Jan 26th GEFS
Current below normal 500mb heights pretty much persist through February 2nd. The TPV passing to our north re-inforces this. Above normal heights arrive from the west on February 3rd. It is a net loss of two days from the previous post (three days). Dollar cost averaging or not, this is a pretty zonal looking flow as of February 3rd with the epo weakly negative (no ridge thru Alaska), +nao, -pna and TPV retraction to Baffin island. Above normal heights persist into February 9th until the TPV starts sinking to Hudson Bay again. The EPS & GEPS do not look like non stop warmth from February 4th thru the 10th, but they do show an overall warmer pattern relaxation.
NAEFS for the week of 2/3-2/10 is confident of near normal temps in our area. Given the way this has worked this winter, i'd say that 8 day period would average above if the ensembles are semi-close.
MJO is currently in Phase 5 (from Mike's site), new outlook is for a more stout MJO for the umpteenth time this winter. Using a two week lag rule, this would support that relaxation depicted and a MJO related return to colder weather thereafter.