bluewave

The MJO slowing in 7 this December focused the greatest departures over Canada and the Upper Midwest. It was the stall in 5 during the December 2015 El Niño that gave us the +13.

If we had the Christmas week departures that they are going to have, we would be in the low 70s instead of the 50s.

Yeah, the Northeast is closer to +5 for December and the upper Midwest is around +10.

I know most people off this forum don’t mind the lower heating costs as December has become more like what November used to be. But another December flash flood at the ski resorts so soon after the Christmas 2020 event is very damaging to the ski industry. Plus people don’t want to be cleaning up flooded basements at any time of year and especially near the holidays.

Another top ten warmest month across the region as we have had something like 20 to 30 top ten warmest months to only one coldest month since the 15-16 super El Niño.

All-time December record high temperatures in Newfoundland and Labrador this week.

Who knows what normal means anymore with our snowfall when NYC goes from the snowiest 5 year period to the 7th least snowiest 5 year period in the same 10 year period. Maximum 5-Year Total Snowfall for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Rank Value Dates Missing Days Period of record: 1871-01-01 to 2023-12-19 1 209.4 2014-01-01 through 2018-12-31 0 2 205.2 1914-01-01 through 1918-12-31 2 3 204.9 1892-01-01 through 1896-12-31 3 4 204.3 1893-01-01 through 1897-12-31 3 5 202.1 1944-01-01 through 1948-12-31 0 6 199.4 2013-01-01 through 2017-12-31 0 7 197.0 1871-01-01 through 1875-12-31 0 8 193.4 1872-01-01 through 1876-12-31 0 9 193.0 2010-01-01 through 2014-12-31 0 10 191.3 1895-01-01 through 1899-12-31 3 Minimum 5-Year Total Snowfall for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Rank Value Dates Missing Days Period of record: 1871-01-01 to 2023-12-19 1 66.1 1928-01-01 through 1932-12-31 0 2 66.2 1927-01-01 through 1931-12-31 0 3 71.9 1951-01-01 through 1955-12-31 0 4 72.2 1950-01-01 through 1954-12-31 0 5 74.8 1988-01-01 through 1992-12-31 0 6 77.0 1949-01-01 through 1953-12-31 0 7 77.7 2019-01-01 through 2023-12-31 12 9 79.4 1997-01-01 through 2001-12-31 1 10 81.8 1973-01-01 through 1977-12-31 0 - 77.7 1971-01-01 through 1975-12-31 0

Pretty wild for Queensland to potentially set the new all-time 12 hr rainfall record during an El Niño when the previous record was during the 71-72 La Niña.

The high temperatures are driving the warm departures for a change so far this month. The +5.1 departure in NYC is an average between a +5.3 max departure and +4.8 min departure. A large portion of the Northern States are +5 or greater.

Yeah, it’s helping to drive the warmth here with the big jet extension.

We have had plenty of hostile patterns in December since 2011, but the snow extent across North America is the lowest in nearly 20 years. https://www.star.nesdis.noaa.gov/smcd/emb/snow/HTML/snow_extent_monitor.html

Most of Arctic air in Eurasia will dump into the Pacific next few weeks and rapidly modify leaving very little Arctic air in the Northern Hemisphere.

Yeah, Nino 4 and MJO 7 overlap so the near record SSTs there produce a very warm pattern for the CONUS in December on the El Niño MJO composite.

Perhaps the MEI isn’t suited for El Niños that have the forcing so far west into the MJO 4-7 regions like this December. The VP anomalies for December so far were more intense than 2015, 1997, and 1982. But are of a similar intensity to 1972 displaced much further west.

NYC continues the record breaking streak of 13 years reaching 55 or warmer from 12-17 to 12-25. The previous record was 11 years from 1998 to 2008. This current streak is even more impressive due to combined number of years over 60° with the 2 years over 70°. Time Series Summary for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Ending Date Highest Max Temperature Dec 17 to Dec 25 Missing Count 2023-12-25 62 7 2022-12-25 58 0 2021-12-25 60 0 2020-12-25 61 0 2019-12-25 57 0 2018-12-25 61 0 2017-12-25 55 0 2016-12-25 58 0 2015-12-25 72 0 2014-12-25 62 0 2013-12-25 71 0 2012-12-25 56 0 2011-12-25 62 0 2010-12-25 40 0 2009-12-25 39 0 2008-12-25 58 0 2007-12-25 61 0 2006-12-25 59 0 2005-12-25 55 0 2004-12-25 59 0 2003-12-25 56 0 2002-12-25 60 0 2001-12-25 58 0 2000-12-25 62 0 1999-12-25 60 0 1998-12-25 63 0

With a little luck our next rain event will hold off until after Christmas. But it will push the rainfall totals this year even higher. Numerous spots are already over 60.00 and NYC and LGA just need a few more inches. FLL will be the most extreme rainfall record this year for the CONUS. Data for January 1, 2023 through December 19, 2023 Click column heading to sort ascending, click again to sort descending. State Name Station Type Total Precipitation CT NORTHFORD 0.8 SW CoCoRaHS 66.73 NY WEST POINT COOP 66.21 CT PROSPECT 1.9 ENE CoCoRaHS 64.77 NY PEEKSKILL 0.4 N CoCoRaHS 64.54 CT SEYMOUR 1.2 WSW CoCoRaHS 64.42 CT NORWICH 2.5 NNE CoCoRaHS 64.16 NY STONY POINT 0.7 NW CoCoRaHS 63.73 CT ANSONIA 1 NE COOP 63.71 NY CARMEL 4N COOP 62.93 NY THORNWOOD 0.7 NW CoCoRaHS 62.74 NY SHRUB OAK COOP 62.55 CT BETHANY 1.3 SW CoCoRaHS 62.53 CT MIDDLEFIELD 0.6 SE CoCoRaHS 62.12 CT GRISWOLD 0.9 N CoCoRaHS 61.66 NY NEW HEMPSTEAD 0.6 SE CoCoRaHS 61.56 CT OAKDALE 2.6 WNW CoCoRaHS 61.51 CT HIGGANUM 0.8 NE CoCoRaHS 61.18 CT COLCHESTER 0.6 ENE CoCoRaHS 60.42 CT EAST LYME 0.5 SW CoCoRaHS 60.38 CT WATERBURY 1.3 WNW CoCoRaHS 60.37 NY BEACON 4.2 ESE CoCoRaHS 60.30 NY SOUTH SALEM 0.8 N CoCoRaHS 59.90 CT HIGGANUM 0.7 N CoCoRaHS 59.87 CT BROOKFIELD 3.3 SSE CoCoRaHS 59.59 CT NEWTOWN 4.6 SE CoCoRaHS 59.41 CT WALLINGFORD CENTER 1.9 WNW CoCoRaHS 59.25 CT RIDGEFIELD 2.4 NNE CoCoRaHS 59.19 CT PROSPECT 0.5 SW CoCoRaHS 58.90 NJ CHARLOTTEBURG RESERVOIR COOP 58.87 NY SOUTH SALEM 2.1 NW CoCoRaHS 58.80 CT CROMWELL 0.4 WNW CoCoRaHS 58.71 NJ WAYNE TWP 2.3 ESE CoCoRaHS 58.68 CT MERIDEN 2.8 WSW CoCoRaHS 58.49 NJ RINGWOOD 3.0 SSE CoCoRaHS 58.47 NY BRIARCLIFF MANOR 1.3 NE CoCoRaHS 58.33 CT NAUGATUCK 1.7 NNE CoCoRaHS 58.31 NY LITTLE NECK 0.3 SE CoCoRaHS 58.27 NY LAGUARDIA AIRPORT WBAN 58.25 CT JEWETT CITY 3.0 ESE CoCoRaHS 58.24 CT NEW CANAAN 1.9 ENE CoCoRaHS 58.19 NJ HARRISON COOP 58.04 CT SHELTON 1.3 W CoCoRaHS 57.93 NY PORT JERVIS 2.9 ESE CoCoRaHS 57.72 NY ARMONK 0.3 SE CoCoRaHS 57.71 NY NY CITY CENTRAL PARK WBAN 57.68 Time Series Summary for Fort Lauderdale Area, FL (ThreadEx) - Jan through Dec Click column heading to sort ascending, click again to sort descending. Rank Year Total Precipitation Missing Count 1 2023 111.90 13 2 1947 102.36 0 3 2020 90.03 3 4 1994 87.25 1 5 1954 85.65 1

This December is a classic case of competing or overlapping influences enhancing the warmth. Have the very strong to super El Niño combined with the warm MJO 4-7 phases. So the US is set to finish around the 3rd warmest December on record since 1950. Only 2015 and 2021 were warmer. It’s no surprise 2015 was at the top of the list with the record MJO stall in phase 5. The double digit departures that month were focused in the Northeast.This December the double digit departures are closer to International Falls and Canada. December 2021 was a La Niña and there was a significant stall in MJO 6-7 which really pumped the Southeast ridge. While super El Niños like 1997 and 1982 were stronger than this year, the MJO activity in December wasn’t in the warmer phases which included the Maritime Continent. So while the location of the El Niño warm departures this month we’re classic El Niño, the magnitude of the departures were enhanced by the warm MJO interaction.

Is this the link that you were looking for? https://www.atmos.albany.edu/facstaff/awinters/realtime/Deterministic_NPJPD.php

Yeah, pretty rough conditions up there today.

Had stronger +EPOs in early December 1952 and 1959. But were still able to manage an Eastern trough with the -AO +PNA patterns. Keep seeing some version of the Southeast ridge with teleconnection combos that it was usually absent in during the past.

December 1982 was much cooler across the CONUS than 2015 and this year. But as we saw in 2015, El Niños combined with MJO 4-7 phases in December are very warm. The double digit departures in 2015 were centered over the Northeast with the record MJO 5 stall. The MJO action this December favored the double digit departures in Canada.

TEB looks like they tied their all-time December high dewpoint of 64°a few hours ago.

Looks like too much of a washing machine for the surfers to go out in Long Beach. https://skudinsurf.com/surfcam/

This may be the first time that we had a +PNA -AO in early December with a weak Southeast ridge.

This month will also feature one of the greatest AO rises on record for December from near -3 to near +3.