bluewave

Stronger winds caused by the persistent +NAO/+AO pattern since 2013. https://www.nature.com/articles/s41467-020-14474-y Abstract The Atlantic Ocean overturning circulation is important to the climate system because it carries heat and carbon northward, and from the surface to the deep ocean. The high salinity of the subpolar North Atlantic is a prerequisite for overturning circulation, and strong freshening could herald a slowdown. We show that the eastern subpolar North Atlantic underwent extreme freshening during 2012 to 2016, with a magnitude never seen before in 120 years of measurements. The cause was unusual winter wind patterns driving major changes in ocean circulation, including slowing of the North Atlantic Current and diversion of Arctic freshwater from the western boundary into the eastern basins. We find that wind-driven routing of Arctic-origin freshwater intimately links conditions on the North West Atlantic shelf and slope region with the eastern subpolar basins. This reveals the importance of atmospheric forcing of intra-basin circulation in determining the salinity of the subpolar North Atlantic. Finally we note that during this period, anomalously strong surface winter heat loss from the ocean to the atmosphere, and the subsequent deep winter mixing contributed to the development of an extreme cold anomaly north of the NAC in the central SPNA53,54.

Big further into the interior around places like Albany. https://www.weather.gov/aly/1-3Dec2019Snow

While that North Atlantic cold pool has been a dominant feature since 2013, it really stands out now due to the record +AO pattern.

It’s all about the context. We have been stuck in a cutter, hugger, and suppressed southern stream storm track for the last two years. So the storm on Monday will hug the coast. Root for the high to hold on long enough so even the coast can see a few wet snow flakes. But the interior continues to be favored for the best. We can all remember the big interior snowfall totals in early December with the MJO 2 passage at the time.

Interior areas look like they are best positioned to cash in on the MJO 2-4 next week.

5th warmest March so far in NYC between 2016 and 2010. Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Mar Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 1945 51.1 0 2 2012 50.9 0 3 1946 49.8 0 4 2016 48.9 0 5 2020 48.8 11 6 1921 48.4 0 7 2010 48.2 0

I hope everyone is well. Picked up close to 1.00”of rain here in SW Suffolk.

It really does. The dewpoints will take another big drop with the near record March high pressure in a few days.

Had a brief heavy downpour and .35 total rainfall. Pretty typical for 2020. Looks like a warm afternoon coming up.

Some heavier rain for a change this morning.

Spring leaf out is 30 days early in NYC.

The was just the warmest first 10 days of March on record for NYC at 48.2 degrees and +9.0. Time Series Summary for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Rank Ending Date Mean Avg Temperature Mar 1 to Mar 10 Missing Count 1 2020-03-10 48.2 0 2 2000-03-10 47.9 0 3 2004-03-10 47.4 0 - 1979-03-10 47.4 0 5 1964-03-10 47.1 0 6 1878-03-10 47.0 0 7 1973-03-10 46.9 0 8 1974-03-10 46.8 0 9 1921-03-10 46.4 0 10 2016-03-10 46.2 0

Another front comes through today with light amounts of rainfall. This is currently the 6th driest start to the year in NYC for the last 30 years. Time Series Summary for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Rank Ending Date Total Precipitation Jan 1 to Mar 9 Missing Count 1 2002-03-09 3.81 0 2 1992-03-09 4.10 0 3 2009-03-09 4.66 0 4 2000-03-09 4.93 0 5 2012-03-09 5.03 0 6 2020-03-09 5.10 0

This warm pattern looks familiar as the Southeast Ridge remains stuck in place.

This is one of those early spring days when we can be drier than the Desert Southwest. PHOENIX FAIR 72 43 35 E7 LAS VEGAS PTSUNNY 67 28 23 E7 Newark Liberty FAIR 73 22 14 W16

Newark at 71 with at a 15% relative humidity. Newark Liberty FAIR 71 22 15 W14

Pretty quick temperature rise to around 60 as relative humidity falls. Newark Liberty FAIR 58 26 29 SW14G20 Stony Brook N 61 28 29 W5

Temperatures rising quickly into the 50’s with the drier conditions continuing.The warm spots should reach the upper 60’s with 70 possible with a guidance beat.

The Southeast Ridge has become a permanent feature.

Beautiful early spring weather. Mid to upper 60’s for the warm spots on Monday. Maybe someone could reach 70 with a guidance beat.

Drier pattern continues. Relative humidity is dropping under 20% early this afternoon. This is the driest start to the year since 2012. Central Park FAIR 46 1 15 VRB7G21 Time Series Summary for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Ending Date Total Precipitation Jan 1 to Mar 7 Missing Count 2020-03-07 5.10 1 2019-03-07 8.17 0 2018-03-07 11.66 0 2017-03-07 7.53 0 2016-03-07 9.06 0 2015-03-07 9.47 0 2014-03-07 8.31 0 2013-03-07 7.20 0 2012-03-07 5.01 0 2011-03-07 10.51 0 2010-03-07 8.85 0

This is just a continuation of the cutter, hugger, and suppressed southern stream storm tracks of the last two winters. It’s the first two winters in a row since the1990’s without at least a NESIS 1 snowstorm. But at least this is the strongest low to pass SE of the BM in a few years.

The last measurable snowfall of 2.1 inches in NYC was on January 18th. So NYC is currently a day ahead of 2002 for the earliest last measurable snowfall. First/Last Summary for NY CITY CENTRAL PARK, NY Each section contains date and year of occurrence, value on that date. Click column heading to sort ascending, click again to sort descending. Year Last Value First Value Difference 2002 01-19 (2002) 3.0 12-05 (2002) 6.0 319 1878 02-01 (1878) 2.0 11-07 (1878) 0.1 278 1925 02-12 (1925) 1.3 10-30 (1925) 0.8 259 2012 02-12 (2012) 0.2 11-07 (2012) 4.3 268 1903 02-15 (1903) 0.3 12-02 (1903) 0.8 289 1986 02-15 (1986) 0.1 12-09 (1986) 0.6 296 1979 02-19 (1979) 12.7 12-19 (1979) 3.5 302

Yeah, that record WPAC warm pool keeps the warm MJO phases going.

This record +AO pattern was more like something we saw around 1990. https://nsidc.org/arcticseaicenews/ Previous studies, led by University of Washington scientist Ignatius Rigor (e.g., Rigor et al., 2002), suggest that a positive winter phase of the Arctic Oscillation favors low sea ice extent the subsequent September. Wind patterns “flush” old, thick ice out of the Arctic Ocean through the Fram Strait and promote the production of thin ice along the Eurasian coast that is especially prone to melting out in summer. However, in recent years, this relationship has not been as clear (Stroeve et al., 2011). The potential effects this winter’s positive AO on the summer evolution of ice extent and the September 2020 minimum bears watching.