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Simon's GEFS 35 day regime forecast does show some indications of a shallow regime change coinciding with the early part of December. In my opinion a temporary cold period such as the one currently might be in the cards. AO drops in the days ahead , possibly towards neutral, as the SPV remains strong well above the ERA5 mean.

Surprised they went with that snowfall prediction. Would speculate lower.

From Bluewave. Maybe a role with the NAO in my opinion Here is his post : Rapidly warming SSTs off our coast go together with the record 500mb ridging that we have been experiencing. https://climate.nasa.gov/news/2798/watery-heatwave-cooks-the-gulf-of-maine/ Most of us are familiar with heat waves on land, but in a warming world, heat waves are starting to become common in the ocean, too. One basin in particular, the normally cool Gulf of Maine in the Northwest Atlantic Ocean, has seen several heat waves in recent years and has spent most of 2018 with unusually warm water temperatures. On August 8, 2018, scientists using satellite data and sea-based sensors measured the second warmest sea surface temperatures ever observed in the Gulf of Maine. Average water temperatures reached 20.52 degrees Celsius (68.93 degrees Fahrenheit) that day, just 0.03°C (0.05°F) below the record set in 2012. The maps on this page show sea surface temperature anomalies as compiled by NOAA’s Coral Reef Watch, which blends observations from the Suomi NPP, MTSAT, Meteosat, and GOES satellites and from computer models. Shades of red and blue indicate how much water temperatures were above or below the long-term average for the region. The map above shows conditions on August 8, the near-record setting day, while the map below shows conditions across the entire month of August 2018. The heatwave of 2018 fits with a much longer trend in the region, which is among the fastest-warming parts of the global ocean. In the past three decades, the Gulf of Maine has warmed by 0.06°C (0.11°F) per year, three times faster than the global average. Over the past 15 years, the basin has warmed at seven times the global average. The Gulf has warmed faster than 99 percent of the global ocean. August 1 - 31, 2018 “We’ve set 10 daily temperature records this summer, after setting 18 this winter,” said Andrew Pershing, chief scientist of the Gulf of Maine Research Institute (GMRI). “We’ve had to add new colors to our temperature illustrations to reflect just how warm the Gulf of Maine has been this year.” In recent years, oceanographers have come to define marine heatwaves as periods when water temperature rise above the 90th percentile (of average temperatures) for more than five days. In 2018, the Gulf of Maine has spent more than 180 days above the 90th percentile. The Gulf of Maine stretches from Cape Cod to Nova Scotia, and it is key intersection between cold water masses from the Arctic and warm water masses from the Gulf Stream. The warming trend in this basin likely has two main causes. First is the overall warming of the global ocean as air temperatures and greenhouse gas concentrations rise. Second is the melting of ice in Greenland and the Arctic Ocean, which provides pulses of fresh water that can alter ocean circulation patterns in the region. “We are seeing a major shift in the circulation in the North Atlantic, likely related to a weakening Atlantic Meridional Overturning Circulation (AMOC),” said Pershing. “One of the side effects of a weaker AMOC is that the Gulf Stream shifts northward and the cold current flowing into the Gulf of Maine gets weaker. This means we get more warmer water pushing into the Gulf.” “Climate change is likely contributing to the circulation changes through melting in Greenland and the Arctic,” he added, “as well as making long-stretches of warm weather more likely.” The warming waters are already affecting marine species in the area, according to several news media and scientist accounts. Herring populations (based on fishing catches) seem to be down this year, and researchers and fishermen are seeing more species usually found in warmer waters, such as butterfish and squid. The populations of copepods, a key food source for endangered Northern Right Whales, also seem to be moving with the changing conditions. And puffins have had to adapt in feeding their chicks this year, as the newly common butterfish are too large for hatchlings to swallow.

Impressive + PMM Pretty classic +PMM Eric Webb @webberweather Despite being in a La Nina w/ subseasonal forcing solidly over the Indian Ocean, the subtropical jet will actually be quite active in late Nov thanks to a positive Pacific Meridional Mode (PMM) event buttressing moist convection in the tropical off-equatorial central Pacific. 4:11 AM · Nov 18, 2020

Yep, will be interesting to watch the progression. Meanwhile, MJVentrice @MJVentrice A strong Stratospheric Polar Vortex is supporting -80C temperatures at 10mb, which is slightly earlier than normal to see these cold of temperatures. 7:34 AM · Nov 18, 2020·Twitter Web App

Matches the Euro weeklies. Comfortable outside decorating weather.

NAM state still looks uneventful. Meanwhile World Climate Service @WorldClimateSvc Today's 46-day ECMWF shows a +4-5°C anomaly for the full month of December in the north-central USA (vs 20-year climatology). At face value that would rival the warmest Decembers on record in Minnesota, such as 2015 and 1997 - both super El Niño winters

Coldest reading so far this Fall at 34 degrees.

GFS having a hard time, ( but what is new ), honestly even the Euro last week was focusing on a -EPO cold air dump. That has changed now. EPS looks very warm for late November and early December. Afternoon BAMWx update :

Interesting, but I think Ben has his MJO phases a bit mixed up.

The same SST feedback issues that support a bad Pac are evident in the Atlantic. The Atlantic's huge rise in SST the last 3 years is the most meaningful and pronounced versus any other part of the globe to a large extent. The WAR is robust not only in the summer but even other seasons as well.

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crazy......

We get our first freeze next week it appears. Avoided 3 freeze warnings so far in my local area.

Little faith in those indices. Many , many false attempts the last 24 months. Enjoy the outdoors late month.

What's new? Everyone on the warm and less snow bandwagon. Simple to see warmth is expanding and the climate is warming. We just broke into another historic anomalous precip event. The tropical jet is changing as well in response to warming. Dominos falling down one after another, rather sad.

Good points. I have noticed over time the CFSv2 trends to the GEFS.

Grass cutting to Jan this year. Soil moisture crazy high, fog every morning, dew points backing up eventually. Thinking ahead to what becomes of the SSTs in the Western Atlantic. They may never really decline that much if this is a very warm winter.

Well the tropical connection still remains in place, another high QPF event is set for later next week. Several disturbances combined with a robust WAR will lead to extreme rainfall possibilities later next week in the East. On a side note, I spoke to some master gardeners and the change in climate here recently, and set in motion due to high dew points and extreme rainfall events since August 2019 , has interesting outcomes regarding plants and cool season grasses. Many seeds remain dormant until conditions arise and these conditions are happening now. Pao trivialis is one and is appearing in many lawns in my area, mine included, no way to selectively kill it unless you kill your lawn as well.

Some indications that the spv and the tpv may start to couple later in the month. From Matt Hugo < Some evidence now as well for +ve uWind anoms to make the link between the strat and trop looking ahead further into Nov, especially between 70-90N. Note how the yellow and orange colours descend from 100hPa down to surface. Another potential sign that blocking is less likely... >

WPC is gradually increasing precip amounts in Days 6 and 7 as you mention.

@psuhoffman will be happy. Adds more ammunition to the very warm and potentially snow-less winter of 20-21

I did mention a couple days back that at the present time there is no direct link between the two ( SPV and the TPV ) and if anything the organizational structures are not ideal for linkage at this time. As I mentioned too, other factors may come into play in December and Jan. I do know that the WPAC warm pool is the warmest it has ever been , much different than 2013-14 and the current background state has never really existed with the significant Pac warmth focused in certain areas against the strengthening Nina . Very interesting to see how things play out.

As a follow up to above. However, keep in mind though other factors are at play too when you look to December and January weather outcomes in the East.

CFSv2 versus the GEFS strat forecats I have been keeping a record and noticing the verification between them, and it seems that the GEFS is schooling the CFSv2 in regards to strat forecast accuracy. This is actually not great news because I see a trend lately with the GEFS strengthening the PV as it slowly gets closer and closer to the ERA5 max. Another nail in the coffin in regards to achieving any significant or long lasting HL blocking.