bluewave

Taste of spring next few days. Widespread 70s today. Some spots may reach 70° again tomorrow. Then a chance of thunderstorms on Saturday which could be locally strong to severe.

https://www.nature.com/articles/s41558-021-01159-7.epdf?sharing_token=_FVaOVyABkcD2Hudkuy4HdRgN0jAjWel9jnR3ZoTv0O_gxR6rgaJtPXjMaI-B_Efht4SyFms8mqqnoqmB-1adVBLGM5Ox8NTZgYnk58C8f_MqmRXlgMUKAvhPoz3ntaVpIMcZZ9PrSyXcXowWePIeqVtKWaAjhHN6qpaUvjsKJPMu2-ItgHqBkpP-ekBm2TbTkyKT4Ld921Svm7C1wJQmod5-Am_0W6rnLf3GjdTJ9U%3D&tracking_referrer=www.theguardian.com Abstract The northeastern United States (NEUS) and the adjacent Northwest Atlantic Shelf (NWS) have emerged as warming hotspots, but the connection between them remains unexplored. Here we use gridded observational and reanalysis datasets to show that the twentieth-century surface air temperature increase along the coastal NEUS is exceptional on the continental and hemispheric scale and is induced by a combination of two factors: the sea surface temperature (SST) increase in the NWS associated with a weakening Atlantic Meridional Overturning Circulation (AMOC), and atmospheric circulation changes associated with a more persistent positive North Atlantic Oscillation. These connections are important because AMOC slowdown and NWS warming are projected to continue. A survey of climate model simulations indicates that realistic SST representation at high spatial resolution might be a minimum requirement to capture the observed pattern of coastal warming, suggesting that prior projection-based assessments may not have captured key features in this populous region.

Models going for the final dynamic warming around March 25th. So we get a brief interruption of the spring pattern with some blocking and cooler temperatures. The persistent La Niña background state returns to start April with a warmer -PNA SE Ridge pattern .

JFK can hit 70° on Friday if the winds stay westerly for long enough. If we keep the offshore flow long enough, then it will be possible. The models have a wind shift in the afternoon. So it may be a race to see how warm we get before the SE flow and clouds arrive.

The warm spots away from the shore in NJ make another run on 70° today. Friday looks like it will be the warmest day of the week. Widespread readings in the 70-75 range.

Another day with high temperatures beating guidance. 65° now at Newark. So Newark moves into 4th place for most 65° days by March 15th. Time Series Summary for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Rank Ending Date Number of Days Max Temperature >= 65 Jan 1 to Mar 15 Missing Count 1 2017-03-15 10 0 2 2000-03-15 7 0 3 1990-03-15 6 0 - 1976-03-15 6 0 4 2020-03-15 5 0 - 2016-03-15 5 0 - 2012-03-15 5 0 - 2008-03-15 5 0 - 2002-03-15 5 0 - 1991-03-15 5 0 - 1974-03-15 5 0 - 1973-03-15 5 0 - 1946-03-15 5 0 2022-03-15 5 0

They get into all those questions with the online presentation that was just posted a few weeks ago. Things like the increasing summer dewpoints in recent years. Why did the lower resolution global climate models miss this. How some higher resolution models are doing a better job but are not perfect. Future areas of research to include increasing heavy snowfall and rainfall. We have been noticing these changes. It’s also interesting how many of the storms correct further north in time. Plus week 2 model forecast cool downs that trend less impressive the closer in time the models get. With 7 warm winters in a row, seasonal forecasts need to include this new data. There have been plenty of outlets that have been too cold with nearly all their winter forecasts since 15-16. So they owe it to their clients to absorb the presentation and correct their seasonal forecasts so their clients can make better decisions.

They already have acknowledged that it has been increasing and the NE Coast is one of the fastest warming areas of the planet. But the climate models aren’t good enough to show it. So they are looking for theories like AMOC slow down and more +NAO. But we have seen the feature with a -AO like last winter with the south based blocking. https://www.nature.com/articles/s41558-021-01159-7 The northeastern United States (NEUS) and the adjacent Northwest Atlantic Shelf (NWS) have emerged as warming hotspots, but the connection between them remains unexplored. Here we use gridded observational and reanalysis datasets to show that the twentieth-century surface air temperature increase along the coastal NEUS is exceptional on the continental and hemispheric scale and is induced by a combination of two factors: the sea surface temperature (SST) increase in the NWS associated with a weakening Atlantic Meridional Overturning Circulation (AMOC), and atmospheric circulation changes associated with a more persistent positive North Atlantic Oscillation. These connections are important because AMOC slowdown and NWS warming are projected to continue. A survey of climate model simulations indicates that realistic SST representation at high spatial resolution might be a minimum requirement to capture the observed pattern of coastal warming, suggesting that prior projection-based assessments may not have captured key features in this populous region.

Could be another active hurricane season with a continuing La Niña background state and that record warm pool off the East Coast.

It’s possible with this persistent La Niña background state since 16-17. Very hard for El Niño’s to get going and couple with the record SSTs near the Maritime Continent. These impressive MJO events just keep reinforcing the La Niña. Nice discussion from the CPC: • The MJO has shown better signs of organization, which is reflected in the observational RMM index and upper-level velocity potential anomalies depicting the leading edge of the main convective envelope shifting eastward over Africa and the western Indian Ocean during the past week. • There is good agreement in the dynamical models favoring continued eastward propagation of the MJO across the Indian Ocean and into the Maritime Continent during the next two weeks. Several ensemble members suggest the possible development of a high amplitude event. • The enhanced phase of the MJO, as well as predicted Kelvin and Rossby wave activity, is expected to increase chances for tropical cyclone formation mainly over the Indian Ocean during the next two weeks. • The potential for the MJO to constructively interfere with the low frequency footprint would favor an extratropical response typical of La Niña, yielding warmer than normal temperatures across eastern North America later in March.

Warm and wet 2nd half of March on the EPS. March 14-21 temperature departures March 21-28 temperature departures March 21-28 rainfall departures

My all-time favorite late season blizzard.

Sometimes we can have both.

The December 2015 extreme +13.3 departure marked the shift to much warmer winters. This is the first 7 year run of above average winter temperatures in our area. The SE Ridge has never been this strong for such an extended period of time.

The first half of March may go into the record books for the warmest -EPO SE Ridge pattern for this time of year.

New all-time record low pressure for one town in NL.

New observations find much greater decline in Arctic sea ice thickness than scientists expected. https://www.washington.edu/news/2022/03/10/newest-satellite-data-shows-remarkable-decline-in-arctic-sea-ice-over-just-three-years/ The newest technology, a combination of ICESat-2 lidar data and CryoSat-2 radar data, is able for the first time to estimate the depth of the snow on top of the Arctic sea ice. Using snow depth and the height of sea ice exposed above water, the study found that multiyear Arctic sea ice lost 16% of its winter volume, or approximately half a meter (about 1.5 feet) of thickness, in the three years since the launch of ICESat-2 in 2018. “We weren’t really expecting to see this decline, for the ice to be this much thinner in just three short years,” said lead author Sahra Kacimi at CalTech’s Jet Propulsion Laboratory.

Less of a temperature range during the summer. But I believe the record was in June 2011 at close to 40°.

Multiple record temperature swings this week in excess of 50° over a short period of time. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=169&network=NJ_ASOS&zstation=EWR&hours=126&month=mar&dir=cool&_r=t&dpi=100&_fmt=png

This event occurred pretty much as expected. It’s tough to get more than a light accumulation near the coast in rain to snow events without a closed low. This storm was really flying along with the progressive +AO and not closing off at 500mb. The Euro gets some points for the earlier mix near NYC. But the RGEM and GGEM did better on snowfall amounts near the coast. The global model errors with the GFS and Euro were too much snow in the first few hours around changeover this morning. But the mesos did better with the quick drying out on the NW flow. The late day snow was a result of the upper low which most mesos did well with.

25° with moderate wind driven snow here in SW Suffolk covering all surfaces now.

Areas that missed out on the first batch of snow today can get another chance with this round.

The south based -AO and -PNA in spring 2010 gave us the record warmth. The -AO remained in place all summer but the -PNA pumped the SE Ridge for record warmth. 2009 was our last really cool summer since the -AO linked up with the +PNA. So the context of how the other teleconnections interact with the AO is important.

The winter AO and NAO states have been defined by increasing positive and negative extremes. So one phase has not been favored over the other since 2010. Strongest -NAO winter in 09-10 on record and most +NAO on record in 2015. Record SPV in 19-20 followed by 2nd highest number -AO days in 20-21. Back to very +AO this winter. So wild swings from one extreme to the other. Spring has been mostly +AO but with a -NAO. So more east based blocking during the spring for some reason. Winter Spring