bluewave

December 3rd will probably be a good sample of what the storm tracks will do this winter. The last 7 winters we have seen a very dominant and fast Northern Steam of the Pacific Jet lead to three dominant storm tracks. Track #1 has been a Great Lakes cutter leading an amplified Southeast ridge and mostly rain near the coast. In this case there is enough separation in the fast Pacific flow for one system to really amplify pumping the Southeast ridge on the day of the storm. Track #2 featured just enough wave separation for an I-78 to I-84 hugger storm track. This has been a snow to sleet and rain scenario along the coast. A bit of a WAR or Western Atlantic ridge on storm day. Track #3 has seen kicker troughs coming into Western North America suppressing the Southern Stream storm tracks. The Benchmark track with a record number of KU snowstorms which has dominated from 2010 to 2018 has been largely absent leading to the record low snowfall last 7 seasons. This has been a result of the much stronger Northern Stream of the Pacific Jet since 2018-2019. If we can get the storm track on December 3rd to show some small deviation, then maybe we can see at least some small improvement this winter. We would want to see a deep enough coastal development near the Benchmark to have some hope in snowfall improvement this winter. Since 1995-1996 we have had 15 La Niña winters as defined by the RONI index. 14 out of 15 of those winters followed a repeating pattern which has been common the last 30 years. EWR, NYC, and LGA December snowfall pattern repeated throughout the entire winter. The Decembers with under 4” of snowfall at those stations went on to below average seasonal snowfall. With the Decembers over 4” or snow featuring average to naive average snowfall. You might ask how can this work out over 90% of the time? My guess is that La Ninas tend to show what they are capable of early on in the season. Plus as our climate has warmed it has lead to more repeating and persistent patterns. So I view this December to winter snowfall relationship more as a marker of a deeper underlying shared pattern rather than something that is directly causing the outcome.

Probably our warmest day of the week today with several spots approaching 60°.

Yeah, this is the reason that we don’t always get a perfect MJO composite match for the RMM charts. Multiple areas of forcing often lead to blended looks between the composites. Sometimes we get more consolidated forcing and it closely resembles a specific phase composite.

I suspect this split forcing is the reason for the volatility that we have been seeing in the models for the first 10 days of December. Models struggle with the placement of features when there are multiple areas of forcing. My only guess that I made earlier for December is that we will have a weaker -PNA and colder Canada than last year.

These long range OP runs can be very pretty. You can see a very broad -PNA trough developing in the ensemble means. Ongoing tug of war between the competing forcing influences On one hand you have the forcing near the Maritime Continent causing the -PNA trough. The 2nd factor is the forcing over the Western Hemisphere trying to build a ridge bridge over the top from Northern Greenland to the -WPO ridge. I suspect this split forcing is why we are getting a composite blend very long range between a Phase 6-7-8 look. The RMMS may try to slow the progression on the 7-8 border in response to split forcing. So at this point I would say early December will feature a broad gradient type pattern with cold across the Northern tier. Mid month will depend on the progression of the forcing. if the ridge bridge over the top wins out, then we will know a phase 8 is trying to take hold. If the -PNA and +EPO become more dominant and the trough pulls back to the west, then we will know the forcing near the Maritime Continent is having a greater influence. Recent experience has favored the 2nd option of a relaxation of the pattern mid to late month. If this doesn’t happen, then we’ll know something new is taking place which we haven’t seen in a while.

The same thing happened back in my old neighborhood of Long Beach. Growing up in the 1970s it was more like Coney Island with numerous boardwalk arcades and an amusement park. Then gentrification began in the 1980s and now multimillion dollar condos took the place of these former attractions. I always found very interesting people living there and it reminded me more of a NYC cosmopolitan neighborhood than a Long Island suburb. Out of all the places that I lived on Long Island, Long Beach had the most character. The condos and apartments below are right where the bowling alley used to be before it closed around 1980. https://www.realtor.com/realestateandhomes-detail/100-Boardwalk-Unit-1001_Long-Beach_NY_11561_M99207-31637 https://www.realtor.com/rentals/details/180-Boardwalk_Long-Beach_NY_11561_M94073-56016

Thanks for posting such beautiful photos. Probably one of the most in demand urban places in the U.S. that people want to move to. You are really lucky to be living in such a charming historic area. https://www.instagram.com/reel/DQZcBGhAEp7/

We haven’t been able to bet on El Niños or La Ninas near NYC over the past 7 winters with how strong the Northern Stream has become. In the old days some of my heaviest snowstorms were during El Niños back on the South Shore up to 2015-2016. These days you really want elevation and latitude in the Northeast.

Even with a very strong -EPO +PNA this fall on the storm days, the Western Atlantic ridge found a way to flex. The composite below is for the 11 wettest days of fall in NYC. The main storm track was still through the Eastern Great Lakes.

Plus we are talking about the long term increasing influence of the Southeast or Western Atlantic ridge on our sensible weather.

I will take warm winter with a cold storm track over a cold or near normal winter and a warm storm track.

December has been one of the most challenging months for sustaining deep -NAO patterns since 2011. Pretty much the opposite of May. This is one of the reasons why we haven’t seen a repeat of record December snows from 2000 to 2010 around NYC.

Mount Mansfield off to a great start.

This is why I would much rather roll the dice with a very strong El Niño even if the winter is very warm like 23-24. We got a one week relaxation from the overpowering Northern Stream which has been dominating last 7 years. The El Niño driven Southern Stream was 2nd strongest on record for DC.

This is also a function of the weaker PNA than last December which we were both expecting. More cold available in Canada than last December. But the same stubborn storm track.

Which is better for the Great Lakes into New England. Gradients usually end up farther north than originally forecast once we get into the short term compared to the longer range forecasts. Models not varying the storm track pattern with a dominant Northern Stream.

The ensembles always show variations with week 2 forecasts. There really hasn’t been that much of a change. Still looking at a Southeast ridge or Western Atlantic ridge and a trough digging into the Baja to start December. New day 6-10 Old day 11-15

The significant trend the models have been showing for early December is more of a Southeast ridge. Of course every run is going to show the departures on any given day being a little different when we are talking week 2 modeling. Some days the ridge will pulse up and others pulse down. But the continuing very fast Pacific flow will continue to limit or storm track options at least into early December.

It’s less important what the long range models are showing since that can vary from run to run. But the long range forecast biases for each type of regime remain more constant over time. Plus the inability of the models to see seasonal repeating patterns until the actual pattern is getting close to occurring.

Same storm track pattern heading into December. Great Lakes cutter, I-78 to I-84 hugger, and suppressed Southern Stream. Plus we haven’t had a gradient pattern work for us in over a decade.

Looks a little above average but noting too extreme like I pointed out in my original post.

We haven’t had any real cold around Thanksgiving since 2018. Data for November 22, 2018 through November 23, 2018 Click column heading to sort ascending, click again to sort descending. NY PORT JERVIS COOP 4 CT DANBURY MUNICIPAL AP WBAN 6 CT OXFORD WATERBURY WBAN 6 NY WESTHAMPTON GABRESKI AP WBAN 6 NJ CHARLOTTEBURG RESERVOIR COOP 7 NY SHRUB OAK COOP 7 NY MONTGOMERY ORANGE COUNTY AP WBAN 7 NY CARMEL 4N COOP 7 CT DANBURY COOP 9 CT MOUNT CARMEL COOP 9 CT MERIDEN MARKHAM MUNICIPAL AP WBAN 10 NY WEST POINT COOP 11 NJ CALDWELL ESSEX COUNTY AP WBAN 11 NY WESTCHESTER CO AP WBAN 11 CT STAMFORD 5 N COOP 12 NY SHIRLEY BROOKHAVEN AIRPORT WBAN 12 CT GROTON NEW LONDON AP WBAN 12 NJ NEWARK LIBERTY INTL AP WBAN 13 NJ CANOE BROOK COOP 13 NJ HARRISON COOP 13 CT IGOR I SIKORSKY MEMORIAL AIRPORT WBAN 13 CT NEW HAVEN TWEED AP WBAN 13 NY UPTON COOP - NWSFO NEW YORK COOP 13 CT GROTON COOP 13 CT NORWICH PUBLIC UTILITY PLANT COOP 13 NY FARMINGDALE REPUBLIC AP WBAN 14 NJ TETERBORO AIRPORT WBAN 14 NY MATTITUCK COOP 14 NY JFK INTERNATIONAL AIRPORT WBAN 15 NY NY CITY CENTRAL PARK WBAN 15 NY CENTERPORT COOP 15 NY ISLIP-LI MACARTHUR AP WBAN 15 NY BRIDGEHAMPTON COOP 15 NY ORIENT POINT STATE PARK COOP 15 Data for November 22, 2018 through November 23, 2018 Click column heading to sort ascending, click again to sort descending. PA POCONO MOUNTAINS MUNICIPAL AIRPORT WBAN -2 NJ SUSSEX 1 NW COOP 5 NJ SUSSEX AIRPORT WBAN 6 PA SPRINGTOWN 1 NNE COOP 7 PA EAST STROUDSBURG COOP 7 PA BELTZVILLE DAM COOP 8 PA LEHIGHTON 1SSW COOP 8 NJ BELVIDERE BRIDGE COOP 8 NJ AEROFLEX-ANDOVER AIRPORT WBAN 8 NJ HIGHTSTOWN 2 W COOP 9 NJ WERTSVILLE 4 NE COOP 9 NJ SOMERSET AIRPORT WBAN 9 NJ NEW BRUNSWICK 3 SE COOP 9 PA BLUE MARSH LAKE COOP 10 PA GRATERFORD 1 E COOP 10 PA SELLERSVILLE COOP 10 PA BUCKSVILLE COOP 10 NJ FLEMINGTON 5 NNW COOP 10 NJ FREEHOLD-MARLBORO COOP 10 NJ BOONTON 1 SE COOP 10

86-87 was one of those years when the 45-“50” amounts went just to our south with the El Niño that year. Data for October 1, 1986 through April 30, 1987 Click column heading to sort ascending, click again to sort descending. SUSSEX 1 NW COOP 70.0 HIGH POINT PARK COOP 53.9 LAKEHURST NAS WBAN 53.3 ESTELL MANOR COOP 48.1 NEW BRUNSWICK 3 SE COOP 47.3 New Brunswick Area ThreadEx 47.3 POTTERSVILLE 2 NNW COOP 46.1 OAK RIDGE RESERVOIR COOP 45.5 INDIAN MILLS 2 W COOP 45.4 HIGHTSTOWN 2 W COOP 44.8

Yeah, missing data interrupts the streaks even though they continue. The only time we had some relaxation of the Northern Stream of the Pacific Jet in recent years was in mid-February 2024. That was when that really narrow snowband in association with the record El Nino STJ streak occurred. But since it was only a one week pattern in such a warm winter, there wasn’t sufficient time for follow up events to occur and end the NYC and LGA streaks. So it upped the odds of the streak continuing at spots like NYC and LGA.

It’s a function of the snow drought that we have been in over the last 7 years that the entire area hasn’t had a daily 4” snowfall. Load the dice for lower seasonal snowfall totals over time and it makes streaks like this more likely. If we had long term continuous snowfall observations at smaller sites than NYC and LGA, then I am sure other spots beyond NYC and LGA would be continuing their under 4” streak also.