frd

I imagine this is good to know in a long term thread. The effects of the SSWE can result in both record cold and record warmth as well as Amy mentions. Example Spain and the heat in Turkey.

Some indications the NAM state may be changing towards early February. Granted, the surface reflection of the SSWE are just now progressing as HM mentioned.

Based purely off of the retrogression in NA combined with movements up top it appears a carving out from the SSWE pushes colder air our way, and very importantly the baroclinic boundary in the process, and may even amplify and increase the tendency for East coast storm genesis. When look at the loops it appears the highest probabilities for this to occur is from Jan 24 th to Jan 29 th. A cool new tool by the way from Simon

Extended blocking is a possibility. @SimonLeeWx MSLP forecasts for February-April from this month's update to the @CopernicusECMWF seasonal suite. Some suggestion of negative NAO lasting into March. Note that JMA, Météo-France, NCEP & UKMO have a weaker SSW signal because they are time-lagged ensembles. @SimonLeeWx Because of the time-lagged ensemble approach used by the Met Office vs. the "burst" approach used by ECMWF, the January C3S update of GloSea5 only had a max. ~40% probability of a major SSW, versus 100% from SEAS5. Very different tropospheric forecasts likely a result of this!

Some so called experts on other boards , not here , get pissy when you mention temps, but it so true. Source region matters despite the massive block.

Canada still above, still awaiting a change, maybe by the end of Jan.

BLOCK

BAMWX corrupted me not to ever believe a forecasted - EPO , my bad. And wow , this is nuts !

Why is this a surprise ? It has happened literally every time. And last winter too. Pac is King .

Rain at 330 hours GFS and 240 GEM. Yea I know OP at range , but we need a real game changer. Same thing last 24 months, cutter, coastal hugger or inland runner.

First time I have seen this expanse of cold over the NH this winter.

If you click on the animation and then go full screen you can see some pretty significant differences later in the forecast cycle. As Ventrice points out the GEFS is much different than the EPS north of Alaska. Focus on the evolution after hour 222. I am sure there are implications for us depending on what outcome wins out. I am guessing we would want the GEFS outcome, leading to colder air masses. T However in both loops you can see the development of the very impressive Baffin Bay block .

CPC AO forecast has trended to the Euro with 2/3 of the members going down after the initial decline that is taking place now. Also the GFS NH NAM index forecast has updated, the latest is the bottom image.

The - NAO will get a big assist going forward as Eric describes.

Can you post the EPO and the WPO from the over night Euro if possible. Thanks

GFS must have the highest verification scores for 360 snowfall forecasts. Bravo

Wonder the impact of the SST profile in the Atlantic. It is much warmer. Blue wave noted that many inland runners, coastal huggers may be due to the shift in Atlantic SST anomalies. I mean really, everything is a hot mess these days.

I agree. Taking a break from tracking. Nice day out. Taking our Greyhound for a walk. Of course looking forward to the GEFS and the EPS. I rather luck out being g too cold because it seems cold is the issue not precip.

@psuhoffman This has to be a positive in my book.

@poolz1

I am with you CAPE but I feel this is one of the best overall winter long range threads on the web

Optimism

Are you including the EPO? I am just referring to the PNA, AO and PNA.

Exactly, the EPS has been wrong many times, while the GEFS has won many forecasts over the Euro Op and the EPS . I say all options are on the table at this time moving forward. The GFS has been extremely erratic, no news there.

@CAPE Paul has had the hottest hand so far in Pac recognition. .