bluewave

The record warmth took a break that May. It was the 5th latest 41 or lower reading on record in NYC. The temperatures rebounded again in July after a close to average June. 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 1961 05-27 (1961) 41 10-28 (1961) 40 153 1925 05-25 (1925) 41 10-10 (1925) 36 137 1963 05-24 (1963) 39 09-24 (1963) 40 122 1907 05-21 (1907) 40 10-19 (1907) 39 150 2002 05-19 (2002) 41 10-15 (2002) 41 148 1976 05-19 (1976) 38 10-18 (1976) 38 151

This is ridiculous for May.

Today was the 8th -10 departure in NYC since April 17th. There were only 2 days with a -10 departure in NYC for all of December through March. TEMPERATURE (F) TODAY MAXIMUM 52 1113 AM 92 1986 68 -16 74 1949 MINIMUM 48 253 PM 32 1891 51 -3 51 AVERAGE 50 60 -10 63

I believe that 5-22-02 was the latest freeze for the coldest spots on Long Island. Frost/Freeze Summary for WESTHAMPTON GABRESKI AP, 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 Season Length 2002 05-22 (2002) 32 10-15 (2002) 31 145 2016 05-20 (2016) 32 10-11 (2016) 31 143 2008 05-20 (2008) 31 10-07 (2008) 31 139 2003 05-19 (2003) 32 10-03 (2003) 29 136 2000 05-16 (2000) 30 10-09 (2000) 32 145 2013 05-15 (2013) 32 10-19 (2013) 32 156 1999 05-15 (1999) 31 10-06 (1999) 31 143

This may be a new surface to 500 mb steep lapse rate record for our area on Saturday.

Euro has some the lowest May 850 mb temperatures on record for Saturday. So it looks like NYC has a good chance to dip below 40 for the first time in May since the 1970’s. NYC may not get out of the 40’s for a high on Saturday. There also could be some wet snowflakes mixed in during the morning. That would tie 1977 for the latest trace of snow on record in NYC. The NYC record low is 35 and low max 44. Record Lowest Max Temperature M 69 94 in 1979 44 in 1977 Min Temperature M 52 74 in 2000 35 in 1947

18z NAM with a rare late season interior snow. Maybe some flakes to the coast behind the storm. Models really struggling with the TPV storm details.

Models continuing with record low May 500 mb heights this weekend. The Euro has a -5 SD event with the TPV. So maybe we can see some flurries if the precipitation coincides with the lowest temperatures in the morning. Would be a tie with 1977 for the latest trace of snow at the coast.

Euro hinting at possibly the lowest 500mb heights on record for May next weekend. The TPV drops into the Northeast with a -4 to -5 SD departure. TPV related storm details can be difficult beyond 120 hrs. But portions of the Northeast can see late season snow along with impressive May cold for most.

Euro continuing with the late freeze idea for next weekend N and W of NYC. Be interesting to see if NYC can actually drop below 40 degrees. Sometimes the OP Euro is too cool for NYC beyond 5 days out. But with the TPV dipping into New England, maybe NYC can pull off 37 to 39 degrees. Frost/Freeze Summary for SUSSEX AIRPORT, NJ 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 Season Length Minimum 04-17 (2016) 10-05 (2019) 151 Mean 04-30 10-16 167 Maximum 05-14 (2013) 10-28 (2011) 188 2019 04-29 (2019) 28 10-05 (2019) 30 158 2018 05-01 (2018) 32 10-18 (2018) 31 169 2017 05-04 (2017) 32 10-17 (2017) 30 165 2016 04-17 (2016) 31 - - - 2015 04-26 (2015) 28 10-17 (2015) 27 173 2014 04-25 (2014) 30 10-20 (2014) 32 177 2013 05-14 (2013) 29 10-21 (2013) 32 159 2012 04-30 (2012) 27 10-12 (2012) 29 164 2011 04-22 (2011) 26 10-28 (2011) 32 188 2010 05-11 (2010) 28 10-10 (2010) 30 151

Newark made it to 80 with the warm downslope flow. Newark Liberty PTSUNNY 80 52 37 W15G22

We get our transient warm up this weekend. But one of the coldest 6-10 forecasts we see this time of year. The blocking pattern right across the pole is as strong as it gets for May.

Looks like mid to upper 70’s today. Probably the warmest day for the first half of the month. While it will feel warm, temperatures will be much cooler than the record heat two years ago. RECORD EVENT REPORT NATIONAL WEATHER SERVICE NEW YORK NY 440 PM EDT THU MAY 03 2018 ...RECORD HIGH TEMPERATURE SET AT NEWARK NJ... A RECORD HIGH TEMPERATURE OF 94 DEGREES WAS SET AT NEWARK NJ TODAY. THIS BREAKS THE OLD RECORD OF 91 SET IN 2001.

Finally getting some more spring-like 70’s this weekend. Models hinting at the first May 30’s in NYC since the 1970’s next weekend. This would mean an unusually late freeze for some outlying areas if it verifies. Time Series Summary for NY CITY CENTRAL PARK, NY - Month of May Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 1977 36 0 2 1978 38 0 - 1976 38 0 - 1970 38 0

Our recent long streaks were 16 days in November 2018 and 22 days in March 2018.

16th day in a row with a negative temperature departure in NYC. This is a rare feat after April 15th. Most of our streaks this long have occurred from November into March. 2020-04-15 -4.9 2020-04-16 -9.3 2020-04-17 -10.1 2020-04-18 -10.5 2020-04-19 -2.8 2020-04-20 -2.2 2020-04-21 -5.0 2020-04-22 -11.8 2020-04-23 -9.6 2020-04-24 -10.5 2020-04-25 -1.8 2020-04-26 -10.1 2020-04-27 -12.4 2020-04-28 -3.2 2020-04-29 -4.5 2020-04-30 -3.0

Sun is out now on Long Island. Looks like the heaviest rains will move through tonight.

This was the first April that Newark didn’t reach 70 degrees.It was also the 3rd lowest monthly max for NYC. First time that Islip stayed below 65 degrees in April. Also the first year that both January and March had a warmer monthly maximum temperature than April. Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of Apr Click column heading to sort ascending, click again to sort descending. Rank Year Highest Max Temperature Missing Count 1 2020 69 1 2 1940 70 0 3 1931 71 0 Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Apr Click column heading to sort ascending, click again to sort descending. Rank Year Highest Max Temperature Missing Count 1 1874 64 0 - 1873 64 0 2 1940 67 0 - 1875 67 0 3 2020 68 1 - 1883 68 0 4 1884 69 0 Time Series Summary for ISLIP-LI MACARTHUR AP, NY - Month of Apr Click column heading to sort ascending, click again to sort descending. Rank Year Highest Max Temperature Missing Count 1 2020 64 1 2 1988 68 0 - 1975 68 0 3 2014 69 0 - 1998 69 0 - 1984 69 0 - 1980 69 0 - 1978 69 0 Monthly Highest Max Temperature for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Year Jan Feb Mar Apr Season 2020 70 62 80 69 80 Monthly Highest Max Temperature for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Jan Feb Mar Apr Season 2020 69 62 77 68 77

No surprise that this was one of the cloudiest Aprils on Long Island around noontime. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=45&network=NY_ASOS&zstation=ISP&hour=12&year=2020&month=4&dpi=100&_fmt=png

Right back to our default -EPO pattern since 2013. Just goes to show how unusual the strong winter +EPO was for this era. Occasionally the -EPO becomes strong enough to flatten out the SE Ridge. This is when we get the odd cold departure month. This EPO reversal returned the PDO back to positive territory after a dip negative.

All the summers since the super El Niño in 2016 had near to record high dew points. The only summer with slightly cooler departures in the 0 to -0.5 range was 2017. The 2016 summer was a top 10 warmest across the area. Numerous top 10 warmest Julys and Augusts during 2016, 2018, and 2019. Time Series Summary for LAGUARDIA AIRPORT, NY - Month of Jul Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2010 82.8 0 2 1999 81.9 0 3 2019 81.5 0 4 2013 81.2 0 5 2016 81.1 0 6 1955 80.9 0 7 1966 80.8 0 8 2006 80.7 0 9 1994 80.6 0 10 2012 80.4 0 Time Series Summary for LAGUARDIA AIRPORT, NY - Month of Aug Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2016 81.6 0 2 2018 81.0 0 3 2005 80.9 0 4 2001 79.8 0 5 2015 79.3 0 6 1995 79.1 0 7 1988 78.8 0 8 2012 78.7 0 - 1955 78.7 0 9 2010 78.6 0 10 2002 78.5 0

3rd highest number of days with measurable precipitation through the 26th in NYC. But the actual amounts were slightly below normal for the month so far. NYC...3.77....-0.17 Time Series Summary for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Rank Ending Date Number of Days Precipitation >= .01 Apr 1 to Apr 26 Missing Count 1 1934-04-26 15 0 2 2019-04-26 14 0 - 1957-04-26 14 0 - 1936-04-26 14 0 - 1929-04-26 14 0 - 1874-04-26 14 0 3 2020-04-26 13 0

Maybe we can sneak in some 70’s from Friday into the weekend. But it looks like another cool down in about a week to 10 days.

You need at least 30-40 years to generate a meaningful trend with the NCDC charts. 10 years is too short a period of time to use on the site. You can generate charts for a wide variety of regions or cites. https://www.ncdc.noaa.gov/cag/divisional/time-series/3004/tavg/3/5/1981-2019?trend=true&trend_base=10&begtrendyear=1981&endtrendyear=2019

Spring has warmed less than all other seasons across our area since 1981. Local seasonal warming since 1981 DJF.......+0.7°F Decade MAM.....+0.4°F/Decade JJA........+0.6°F/Decade SON.......+0.8°F/Decade