bluewave

NYC needs to get down to 13° tomorrow in order to beat the lowest temperature of the last two winters. Time Series Summary for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Ending Date Lowest Min Temperature Oct 1 to Apr 30 Missing Count 2021-04-30 14 0 2020-04-30 14 0 2019-04-30 2 0 2018-04-30 5 0 2017-04-30 14 0 2016-04-30 -1 0 2015-04-30 2 0 2014-04-30 4 0 2013-04-30 11 0 2012-04-30 13 0 2011-04-30 6 0 2010-04-30 13 0

Yeah, also an impressive week 2 Arctic outbreak signal from an ensemble mean for much of the CONUS.

Yeah, numerous opportunities with so many shortwaves rotating around the Hudson Bay vortex in mid to late January.

I am very sorry for your loss. Yeah, the long range models have been pretty insistent in the IO convection firing near the warm pool south of India by February. MJO phases 2 and 3 can be good for us during a La Niña in February. But convection shifting closer to phase 4 would allow the +PNA ridge to pull back close to the Aleutians. So it will be interesting to see what the models come up with as we get closer to February.

It will be interesting to see how long we can keep the MJO away from the Maritime Continent after the recent SST cooling in that region.

Yeah, looks like a very active pattern on the EPS. This is one of the most dramatic December to January Pacific reversals that we have ever seen. The models are looking very Nino-like after one of the most extreme La Niña Decembers on record. Recent SOI drop 9 Jan 2022 1007.02 1008.30 -27.74 8.33 9.43 8 Jan 2022 1008.45 1008.65 -22.65 9.56 9.77 7 Jan 2022 1011.09 1008.10 -7.63 10.53 9.97

The trick is for the GFS to show these solutions and then lose them and then have them suddenly pop up again within a week as the STJ becomes more active.

It will be interesting to see how long we can hold this pattern.

It’s telling us that the pattern has features resembling an El Niño even though it’s a La Niña winter. From the CPC: Dynamical model 500-hPa height anomaly forecasts depict a shifted pattern than what has been observed during the early Boreal winter period, indicating at least a temporary departure from the canonical La Nina response.

Atlantic City is already approaching its snowiest January on record and it’s only the 8th of the month. This much snow in the past has occurred under El Niño and ENSO neutral patterns. So it goes to show the more Nino-like aspects we are seeing this month. Time Series Summary for Atlantic City Area, NJ (ThreadEx) - Month of Jan Click column heading to sort ascending, click again to sort descending. Rank Year Total Snowfall ENSO 1 1987 20.3 El Niño 2 2014 18.8 neutral 3 2022 17.2 La Niña 4 2016 16.7 Super El Niño 5 1961 15.9 neutral

Models will probably struggle more than usual with storm details beyond 3-5 days. We are currently getting a Nino-like SOI drop. So a shift from a split flow to a dominant STJ pattern. This type of jet stream shift can introduce plenty of long range model volatility. SOI 8 Jan 2022 1008.45 1008.65 -22.65 9.56 9.77 7 Jan 2022 1011.09 1008.10 -7.63 10.53 9.97 Current split flow pattern Transition to more Nino-like dominant STJ pattern

It looks like the ASOS may have undermeasured the actual liquid equivalent of the snow. The NWS has noted this at certain ASOS stations in the past during heavy snows. Other North Shore observers picked up nearly .50 of precipitation https://storymaps.arcgis.com/stories/96964b6457794d2196dff24d68d4688d Sometimes the Automated Surface Observing System (ASOS) can struggle to melt snow for liquid equivalent in heavier snowfall. Station Number: NY-QN-39 Station Name: Little Neck 0.3 SE Observation Date 1/7/2022 7:00 AM Submitted 1/07/2022 7:22 AM Total Precip Amount 0.49 in. Notes 27° snow reading 7:10 AM Taken at registered location Yes Snow Information New Snow Depth 7.8 in. New Snow Water Equivalent 0.49 in. Station Number: NY-NS-42 Station Name: Albertson 0.2 SSE Observation Date 1/7/2022 7:30 AM Submitted 1/07/2022 8:27 AM Total Precip Amount 0.44 in. Notes -- Taken at registered location Yes Snow Information New Snow Depth 7.5 in. New Snow Water Equivalent 0.51 in. Total Snow Depth 7.5 in. Total Snow Water Equivalent 0.51 in.

While the ratios were very high across the area, it’s possible that some of that some of that ratio calculation was a result of ASOS error. https://storymaps.arcgis.com/stories/96964b6457794d2196dff24d68d4688d Sometimes the Automated Surface Observing System (ASOS) can struggle to melt snow for liquid equivalent in heavier snowfall. This may have led to the 22:1 ratio, which is rare in this part of the country.

This new pattern for us emerged in January 2005 . We had one of the warmest first two weeks of January on record. Followed by a record high of 66° on the 14th and a KU on the 22nd. Seasons since 1950 when at least one station from Newark to Eastern LI recorded 40”+ and the NYC DJF average temperature. 35°+ average temperature seasons bolded 20-21….36.1 17-18….36.2 16-17….39.3 15-16….41.0 14-15…31.4 13-14…32.9 12-13…36.8 10-11….32.8 09-10…33.8 08-09…34.2 05-06…37.3 04-05…35.4 03-04…32.4 02-03…31.2 00-01….33.5 95-96…32.2 93-94…31.2 86-87….34.8 77-78….30.8 68-69….32.9 66-67….34.1 63-64…33.2 60-61….31.7 57-58…33.2 55-56…32.8 Last winter it was our best December snowstorm and -AO in years with bookend 60° days. May 2020 tied for our latest trace of snow following one of our warmest winters. 17-18 featured 30” of snow in March on Long Island after Newark hit 80° in late February. We had the blizzard in February 2017 a day after the 60s. 15-16 went +13.3 in December followed by the 30” snowstorm in January and new #1 NYC snowstorm. Even before the super El Niño, we were getting occasional patterns like this. Nemo in February 2013 following the very warm first few months of winter. The 11-12 lack of winter after the record snowstorm in late October. The February 2006 NYC #2 snow following one our warmest Januaries on record. The late winter 2005 snowstorms following one of the warmest first 2 weeks of January on record. This is a sea level version of spring in the Rockies where snow and warmth have often occurred together.

This is the only snowstorm in the area during the first week of January with a 60° high temperature. We saw the first 12”+ daily snow at ACY following a 60° day. This has been a common theme for us in recent years with record warmth and heavy snows close together. Time Series Summary for LAGUARDIA AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Rank Ending Date Highest Max Temperature Jan 1 to Jan 7 Snow 2007-01-07 72 0.0 1950-01-07 66 0.0 1993-01-07 64 T 2000-01-07 63 0.0 1998-01-07 63 0.0 2012-01-07 62 0.0 1946-01-07 62 T 2008-01-07 61 T 1997-01-07 61 0.1 2022-01-07 60 8.4 2019-01-07 60 0.0 1966-01-07 60 T

This is the most dramatic December La Niña to January positive flip without a SSW. The SSW Januaries still maintained the La Niña background forcing state. This one is all by itself with the pronounced Nino-like forcing near the dateline and WWB pattern.

This may be the most extreme reversal of a La Niña pattern in December to a much more Nino-like one in January. The forcing near the Dateline and WWB would be impressive for a regular El Niño January. It will be interesting to see what type of pattern shows up in February.

Just measured 6” here in SW Suffolk.

The HREF max snowfall did a great job with the wider area of 6”+ than the other guidance. Also had the heaviest amounts going to our Northeast. The HREF also did very well with the summer flash flood events.

Yeah, the forcing keeps following where the strongest marine heatwaves are located. This month the record SSTs shifted closer to Dateline. There has been some cooling north of Australia where the convection was stalled out in December. Now the forcing forecast for a large part of January is more Nino-like near the Dateline.

SPC HREF has the best 6” potential where the banding sets up.

Yeah, the La Niña just became one of the most east based events on record. So Nino 4 has warmed back closer to neutral in recent weeks. This allows the forcing to stall closer to the Dateline for a while. That’s the key to maintaining more of a Nino-like +PNA.

Spots that get into the banding will have the best shot at reaching 6”.

The last several years have been famous for weather patterns that haven’t matched the ENSO background state. Competing marine heatwaves and MJO stalls have created some very wild patterns. The current very strong VP anomalies near the Dateline is much more El Niño-like. So it’s no surprise that the recent STJ pulse produced the record snows just to jour south like in an El Niño winter. The SE trough in the long range forecast would match with such strong forcing near the Dateline.

Hopefully, we can keep this pattern going for as many snow chances as possible. Euro has the -EPO/+PNA /south based Atlantic block continuing into the long range. Maybe the weeklies tomorrow will have some clues for what comes even later in January.