bluewave

There has been some research that the IOD could possibly impact the NAO and AO. Maybe the record +IOD from November into December was in some way responsible. Some of our other extremely +AO +NAO events were preceded by strong MJO 2-3 forcing. It could be that the IO standing wave from November into mid-December played a role. But we’ll probably need a a study to confirm. https://journals.ametsoc.org/doi/10.1175/JCLI3577.1?mobileUi=0& The dominant pattern of atmospheric variability in the North Atlantic sector is the North Atlantic Oscillation (NAO). Since the 1970s the NAO has been well characterized by a trend toward its positive phase. Recent atmospheric general circulation model studies have linked this trend to a progressive warming of the Indian Ocean. Unfortunately, a clear mechanism responsible for the change of the NAO could not be given. This study provides further details of the NAO response to Indian Ocean sea surface temperature (SST) anomalies. This is done by conducting experiments with a coupled ocean–atmosphere general circulation model (OAGCM). The authors develop a hypothesis of how the Indian Ocean impacts the NAO. By analyzing model simulations we found that the South Asian jet can act as a waveguide with circumglobal teleconnection in the Northern Hemisphere. The meridional wind pattern, associated with this circumglobal teleconnection, is connected with the North Atlantic Oscillation. A warming/cooling in the Indian Ocean, especially in the western Indian Ocean, produces anomalies in the South Asian jet. The waveguiding effect of the South Asian jet carries the perturbation into the North Atlantic sector and leads to a NAO-like response. The observed recent positive trend in the NAO has likely contributions from the observed warming in the Indian Ocean. Our analysis—confirmed by the observed trend in the western South Asian jet and the anomaly pattern of the 300-hPa winter meridional wind—indicates that the change of the NAO may be via the circumglobal pattern. https://journals.ametsoc.org/doi/full/10.1175/JCLI-D-15-0502.1?mobileUi=0 The teleconnection patterns associated with phases 3 and 7 are also important for Atlantic blocking. In agreement with Lin et al. (2009) and Cassou (2008), 10–15 days after MJO phase 3 a positive NAO pattern develops over the Atlantic. We find that Atlantic blocking frequency is more than halved in association with the positive NAO pattern. In contrast, MJO phase 7 is followed by a negative NAO pattern, which coincides with a high-amplitude wavelike flow and an increase in blocking frequency. Atlantic blocking frequency is almost doubled following phase 7, reaching +16.5% relative to climatology. Approximately 14%–15% of all DJF Atlantic blocked days follow phase 7.

Newark reached a record high of 60 degrees today. This was the 4th time near the start of February since 2017 to go 60 or warmer. It was also the 2nd record high. Last year came within a degree of a record tie. 2/4 69 in 1991 61 in 2019 59 in 2020 2/5 69 in 1991 68 in 2019 57 in 1993 2/6 69 in 2008 59 in 1938 57 in 2005+ 2/7 60 in 2020 55 in 1990 54 in 2005 2/8 65 in 2017 63 in 1965 62 in 1933

I posted them the other day. The EPS has been the best scoring model after 5 days. While all models have a had a cold bias beyond 5 days, the GEFS has been much worse. http://www.frontierweather.com/verification.html

March 2018 was the last time that it happened for us.

Gusting to 63 mph at Islip.

Staten Island just gusted to 49 mph with the squall. http://www.nysmesonet.org/mesonow#network=nysm&stid=stat

2” per hour rates in the cold sector.

60 degrees now on Staten Island. http://www.nysmesonet.org/mesonow#network=nysm&stid=stat

Winds increasing quickly now on the South Shore with Gilgo Beach gusting to 42 mph. https://www.wunderground.com/dashboard/pws/KNYBABYL18/table/2020-02-7/2020-02-7/daily

Warm front just came through here on the South Shore. 51 degrees and south winds gusting to 24 mph in Wantagh.

We continue to see the 240hr SE ridge correct stronger than the 360hr forecast.

The warm sector where the high winds will develop is already into Philly. They jumped 8 degrees from 48 to 56 in just 30 minutes. Winds are now gusting close to 40 mph with pressure at 982 mb. http://wxweb.meteostar.com/meteogram/link.shtml?choice=KPHL

This has to be one of the fastest Atlantic crossings for such an intense storm.

At least somebody is getting record snowfall.

The February record for the western half of CT was set just 10 years ago. At that time we were setting records for the -AO instead of the +AO now.

Parts of CT could challenge their all-time February record lowest pressure on Friday.

The Pacific Jet continues to set records.

Long Island could see higher gusts than that since it will be closer to the strongest LLJ near frontal passage. The warmer surface temperatures should really steepen the low level lapse rates for good mixing along and behind the cold front. Euro has highs in the low 60’s.

Areas around NYC are on track for their first sub 980 mb pressures since 10-29-17. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=18&network=NJ_ASOS&zstation=EWR&sdate=2017%2F01%2F01&days=1000&var=mslp&dpi=100&_fmt=js

At least Philly can brag that they beat 72-73. Time Series Summary for Philadelphia Area, PA (ThreadEx) Click column heading to sort ascending, click again to sort descending. Rank Ending Date Total Snowfall Oct 1 to Apr 30 Missing Count 1 1973-04-30 T 0 2 2020-04-30 0.3 86 3 1998-04-30 0.8 0 4 1950-04-30 2.0 0 5 2012-04-30 4.0 0 - 2002-04-30 4.0 0 7 1931-04-30 4.1 0 8 1919-04-30 4.5 0 9 1951-04-30 4.6 0 10 1992-04-30 4.7 0