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Bizarre. Lake effect band just came through with a burst of snow and thunder! WTF

Care to explain the reasoning why the pattern post 2019 has been to utterly hostile to cold and snow in the northeast specifically ? Other regions aren't experiencing this.

My 4 weeks post was simply looking at the previous years with early warming events, looking at the following weeks & in those few years this has occurred, it appeared to be around 4 weeks the troposphere was clearly being affected by the event, which I found interesting. Great post Don & much needed...as usual!

BWI: 21.2 DCA: 13.8 IAD: 24.7 RIC: 7.5 SBY: 11.1

Yeah my professor was highlighting the off-the-scale wind anomaly within the last few days. He does think that the MJO will wrap back around before reaching 8 and usher in a more central US trough for the latter part of December. Fairly confident that the beginning will be cold though.

Yeah, by no means am I suggesting it will happen, it was one of those things that I was envisioning that maybe we can sneak in with the block helping him provide some cold air, especially for the interior.

What's the elevation at your house?

There can be immediate affects on the troposphere if the SPV & troposphere are strongly coupled which does not appear to be the case at the moment. If it gets immediately cold in early DEC it is not from the affects of the SSWE. And obviously there are no guarantees of how the SSWE later shakes out in the troposphere, we can only use analogs to guess.

Yeah maybe. It's a tweener system. It's in between teleconnectors, wedged in that timing between more major or obvious signals. If it is even real, confidence will come down to handling the daily noise. I mean, when it is resulting/connected to larger mass field change, confidence in actually having 'something' on the charts can be assessed at longer leads... But that thing's pretty invisible to the indices. Tweeners are real though. They can sting. "Little critters that bite" are tweeners. Or like the 1997 Dec 23 snow bomb storm was a tweener. I saw 16" from that one.

says the troll who hasn't gotten it for the last few years.

BWI: 18 DCA: 8 IAD: 22 RIC: 15 SBY: 10

The ice age hype is coming from the usual hysteria crowd. The headline today is Gulf Stream will shut down, leading to oceans rising and an ice age. Yeah, figure that one out. It is all about clicks and if you are a scientist looking for pal review, funding, which now is the same as clicks.

This is going to trigger DIT.

Next time Peter Geiger stops in, I'll have to ask him why they chose to no longer publish the Farmers Almanac.

"We are pleased to share the Maryland Climate Bulletin for October 2025, which includes sea surface temperatures for the Chesapeake Bay and the state's coastal waters. However, due to the federal government shutdown, the availability of our primary data source for the Bulletin has been affected, and consequently, the extent of the Bulletin has been impacted. The regular production of the Bulletin is only possible thanks to the hard work and data provided by our friends at NOAA National Centers for Environmental Information, the CoastWatch East Coast Node, the Institutions involved in the U.S. Drought Monitor, and the U.S. Geological Survey's Water Watch. You can access the Bulletin from the following link: https://mdsco.umd.edu/Bulletin/bulletin_mdsco_current.pdf Points to highlight are: 1) Statewide averages indicate that October 2025 was slightly colder and drier than normal (i.e., 1991-2020 averages). 2) Regionally, the mean temperature was warmer than normal in some areas of the state, particularly over counties in the central Piedmont and the Eastern Shore. Colder-than-normal conditions appeared over parts of Garrett, Prince George's, and Charles counties. 3) Precipitation was below normal for most of the state, especially over portions of Saint Mary's, Charles, Calvert, Somerset, Dorchester, and Talbot counties, which received around 50% less precipitation than normal for the month. Above-normal precipitation was observed only over western Washington County, which received approximately 25% more precipitation than normal. The rest of the state, with below-normal precipitation, received around 25% less precipitation than normal. 4) Drought conditions deteriorated in October. The extent of the state affected by drought increased from 50% to 90%, with a rise in the areas having Abnormally Dry and Moderate Drought conditions. Moderate Drought conditions affected Garrett, Allegany, Washington, Frederick, and Montgomery counties, as well as western Carroll, Howard, Prince George's, Charles, and northeastern Cecil counties. The Severe Drought conditions in Garrett and Washington counties, and the Extreme Drought conditions in Garrett County that appeared in September, persisted into this month. Abnormally Dry conditions covered the rest of the counties in the Piedmont, and most of the counties on the Eastern Shore; Worcester and Queen Anne's counties, as well as parts of Wicomico and Kent counties, remained drought-free. The number of streams and rivers experiencing Below-normal and Much-below-normal streamflow increased this month. 5) The Chesapeake Bay sea surface temperatures (SST) in October 2025 were in the 63−70°F range. Regionally, they were below their 2007–2020 mean across much of the Bay, except in the waters north of Baltimore, extending into the Upper Bay, where warm anomalies exceeded 4°F. The coldest anomalies were found in the southeastern Lower Bay, in the Tangier Sound waters off Somerset, Wicomico, and Dorchester counties, as well as in the Chincoteague Bay (3–4°F below). The all-basin mean temperature of 66.3°F was still warmer than the coldest October in the 19-year dataset (2007-2025), which recorded a temperature of 62.2°F in 2002. Please refer to the Bulletin for more details. The Maryland Climate Bulletin is issued monthly and presents the state's recent surface temperature and precipitation conditions in a clear and concise format, enabling Marylanders to better understand regional climate variations. Please help disseminate this Bulletin. Thanks, Alfredo -- ............................................. Alfredo Ruiz-Barradas, PhD Associate Research Professor Maryland State Climatologist"

Just need to see the same model output in the 2-4 day range

When it comes to sudden stratospheric warming events (SSWEs) or major stratospheric warming events (MSWEs), these events can be a response to strong blocking (bottom-up), which often reinforces and extends the blocking. They can also be top-down events that lead to a downward-propagating tropospheric response. Typically, there is approximately a 10-20-day lag, where the NAO/AO move toward and into a negative state. This blocking can then persist for 30 days and longer, with some fluctuations. Tropospheric responses to vortex-splitting events are often stronger than those for displacement events. However, more often than not, the larger portion of the split vortex winds up in Eurasia and the smaller one moves into North America. So, if the sudden or major stratospheric warming event occurs in the closing days of this month, its impact on North America would probably start to be seen near mid-December +/- few days. Right now, a major event with a wind reversal isn't assured. Also, the warming and wind reversal appear to be centered mainly south of 60N vs. the 60N-90N region that is conducive to triggering or extending Arctic blocking. Warming events centered south of 60N often do not produce the same downward-propagating tropospheric impacts of those that occur in the 60N-90N region. That's an important detail that will need to be considered.

You know ... speaking of diatribes ( lol ) ... wrote this paragraph in that missive, "At this stage of our species evolution we are brilliant enough to suspect if not outright predict calamity, yet too stupid to believe those visions ... Immediate gratifications and/or preexisting interests that have to be suspended in lieu of what those visions might suggest, becomes a conflict that won't be resolved until people see the death, and feel the pain." and it's too generalized. What's really going on is that a tiny fraction of living humans are brilliant enough to suspect if not outright predict calamity, but they cannot effect change because they are limited by the insurmountable masses of population that are too stupid to believe those visions ... There is a pyramid ignoramus dilemma. It's always been a problem for science that a single person .. or small constituency, discovers something huge, capable of truly revolutionizing an understanding of reality - necessarily so if we are all to be 'real' - but they are at the tip founded upon generations of tradition and functioning, unwitting false belief systems.

That’s more important to snow around here in December than the NAO

I’m still looking for strat. zonal wind data for 1983 and 1989. In the meantime, I did find the following graph, which is of 65N to 90N zonal mean temperatures at 10 mb in 1988 and 1989. Look on the far right: although there was no major SSW in any of the tables I look at (meaning no reversal of zonal winds at 10 mb), you can see there still was a bit of a stratospheric warming spike centered on ~Dec 1st of 1989 to near a record high for that date: https://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/archive/10mb9065_1989.gif —————— This is even more evident further up at 5 mb and at 2 mb: 5 mb: 15C spike warming centered near 12/1/1989: https://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/archive/05mb9065_1989.gif ————— 2 mb: 15C spike warming centered near 12/1/1989: https://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/archive/02mb9065_1989.gif

How many of them have a link they want you to click so they can get subscriptions? Look I don’t doubt there could be a cold/snowy December and many signs are pointing that way, but the “major cold and snow11!111!!” should be met with skepticism.

The only unusual element is in the event that the zonal wind actually reverses this early, which is still dubious IMHO. This is the latest example of how online forecasting is more geared towards attracting attention and generating revenue, as opposed to adding actual value.

Same here - we’ve been stuck at 31.8 with light snow. Looks great though!

After a true winter's day two days ago (29/16), it didn't make it below freezing last night and poof, there went our little snow cover. Going to be beautiful the next few days at least.

Soon, Barney will come to an eastern US location near you!