bluewave

My only regret over this period is that I missed out on the Nemo 6” per hour 50 DBZ band. But maybe we can see something like that in the 2020s closer to our area. Be interesting to see if we can get a 40” event like BGM did in December.

Remarkable snowfall run since 02-03. Even winters with above normal temperatures have been able to produce above normal snowfall. Below normal snowfall years like 06-07, 07-08, 11-12, 18-19, and 19-20 have been the exception rather than the rule.

Our first 60° day since Christmas.

Yeah, long term SST warming is boosting the expectations for what is considered a normal Atlantic hurricane season.

Yeah, a new study indicates that the active phase that began in 1995 may be more of a new normal. With warming Atlantic SSTs, we may not be able to count on a less active phase happening again like the 1970s and 1980s. Another study just out reinforces the idea of the warm pool remaining in place to our east. We saw how the warmer SSTs and higher pressures there last summer lead to an active close in storm track.

This will be only the 6th time since 1991 that NYC had to wait until March for the first 60°+ day of the year. But it’s the first time following a warmer than average winter. So you can see how rare the winter south based blocking pattern was. 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 First Value DJF AVG Temp 2015 03-26 (2015) 62 31.4 2003 03-16 (2003) 68 31.2 2014 03-11 (2014) 66 32.9 2010 03-08 (2010) 61 33.8 2004 03-01 (2004) 63 32.4 2021................................................36.1

GFS continuing with the first -5 to +5 AO rise in such a short period of time. 2021 2 10 -5.285 2021 2 11 -5.254

The bigger AO swings since 2010 have made seasonal AO forecasting even more challenging. https://climexp.knmi.nl/getindices.cgi?WMO=NCEPData/cpc_ao&STATION=AO_CPC&TYPE=i&id=someone@somewhere

If that +5 verifies, then I believe it would be the first time that the AO rose from under -5 to +5 in just 30 days.

I guess we had to know that the MJO would eventually make it to phases 8-1.

March and November are the few months of the year that bucked the big warming trend since 2010.

This was the 2nd most backloaded DJF period on Long Island since 2010. Only Nemo in 2013 featured a more lopsided February snowfall total relative to December and January. 09-10 was more a bookend winter on Long Island. Monthly Total Snowfall for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. Year Dec Jan Feb Season 2012-2013 0.6 3.3 31.4 35.3 2020-2021 7.5 1.1 24.9 33.5 2013-2014 8.1 25.2 24.5 57.8 2009-2010 25.3 6.4 21.7 53.4 2016-2017 3.2 14.0 14.7 31.9 2014-2015 0.4 30.2 13.4 44.0 2015-2016 T 24.8 13.2 38.0 2010-2011 14.9 34.4 3.9 53.2 2018-2019 T 0.9 3.5 4.4 2017-2018 6.0 22.0 1.4 29.4 2011-2012 T 3.8 0.6 4.4 2019-2020 4.2 2.5 0.0 6.7

We were as backloaded as Glasgow was frontloaded.

More confirmation of the GFS cold bias fix.

The AO reversal in February continues to set records. This is the first February with a daily -5 reading and only a monthly -1 average. The previous -5 drops in 2010, 1978, and 1969 all had -3 and lower monthly averages. https://ftp.cpc.ncep.noaa.gov/cwlinks/norm.daily.ao.index.b500101.current.ascii https://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/monthly.ao.index.b50.current.ascii.table 2021 -2.484 -1.191 2010 -2.587 -4.266 1978 -0.347 -3.014 1969 -2.967 -3.114

The lack of multi-year ice has finally allowed the 1st transit of the Northern Sea Route in February.

The more slowly warming spring temperatures relative to the other seasons is reflected in the new 1991-2020 climate normals.

The spring of 2010 was a real outlier. Spring is the slowest warming season for us since 1981. So our springs usually feature a back and forth between warm and cool. But the warmer temperatures still have won out. Just not as lopsided as the other seasons. https://www.ncdc.noaa.gov/cag/divisional/time-series/3004/tavg/3/5/1981-2021?trend=true&trend_base=10&begtrendyear=1981&endtrendyear=2020 Seasonal warming for our area since 1981 DJF.........+0.8° F per decade MAM......+0.4°F JJA........+0.7°F SON.......+0.8°F

Euro coming in even warmer now for next week. Has the first 60s of the year by next Tuesday. Then it has a chance for some of the warmer spots to reach 70° by later next week. Looks like the big AO rise will really amp up the SE Ridge for a while.

That 1995 event was near the start of high dewpoint era. Matches the steep increase in minimum temperatures. 110°+ heat indices have occurred in 1993,1995, 1999, 2010, 2011, and 2019.

Yeah, the minimums are rising quickly at both urban and rural sites. POU has fewer July lows in the 40s. While the NYC lows in the 50s have been harder to come by.

The NYC years since the 1990s would be much warmer than the 1950s to 1980s if the sensor wasn’t blocked by the thick vegetation. The warmest 30 day periods at EWR and LGA were in more recent times. So we can add a few degrees to the more recent NYC warmest 30 day periods. warmest 30 day periods LGA 83.8...2010 83.3...2020 82.9....2005 82.8....2016 82.7....2006 82.5....2013 82.4....1999 81.9....1995 81.7....2019 81.8....1966 81.6....2012 81.5....1980....1955 EWR 83.6....1993 83.4....2011 83.1....1988 82.9....2010 82.6....2013 82.2....1994 82.0.....2005 81.9.....1999 81.6.....2012 81.4.....1980 81.3.....2016 81.2.....2020 81.1.....1955 80.6.....1966...1979 80.5.....1973

Yeah, the two most memorable heatwaves of the 1970s were late August into early September 1973 and mid-July 1977. The brief heatwave around 7-4-74 was also memorable since is was in the mid 90s for the July 4th celebrations. The 70s heatwaves usually didn’t last too long. Even the famous 1977 heatwave dropped into the 50s a few days later. NYC when the sensor was in the shade under thick foliage 1977-07-13 93 73 83.0 6.4 0 18 0.00 0.0 0 1977-07-14 92 73 82.5 5.8 0 18 0.00 0.0 0 1977-07-15 96 72 84.0 7.3 0 19 0.00 0.0 0 1977-07-16 98 75 86.5 9.8 0 22 T 0.0 0 1977-07-17 97 78 87.5 10.7 0 23 T 0.0 0 1977-07-18 100 78 89.0 12.2 0 24 0.00 0.0 0 1977-07-19 102 78 90.0 13.2 0 25 0.00 0.0 0 1977-07-20 92 75 83.5 6.7 0 19 0.06 0.0 0 1977-07-21 104 78 91.0 14.2 0 26 0.00 0.0 0 1977-07-22 88 68 78.0 1.2 0 13 0.00 0.0 0 1977-07-23 87 62 74.5 -2.3 0 10 0.00 0.0 0 1977-07-24 90 70 80.0 3.2 0 15 0.00 0.0 0 1977-07-25 78 70 74.0 -2.8 0 9 0.48 0.0 0 1977-07-26 82 62 72.0 -4.7 0 7 0.00 0.0 0 1977-07-27 81 58 69.5 -7.2 0 5 0.00 0.0 0