bluewave

Classic spring warm day temperature distribution around the area. Jones Beach N/A 59 N/A N/A S10G16 N/A Wantagh N/A 66 50 55 S12 N/A Kennedy Intl PTSUNNY 77 48 35 SW15 29.72S LaGuardia Arpt MOSUNNY 82 44 26 W12G21 29.68F Newark/Liberty PTSUNNY 83 45 26 SW24 29.70S

The Euro had the morning showers with warm front moving through. Should see a big temperature jump this afternoon. So 80+ for the areas in NJ that get warm sectored is still on track.

The MJO was less robust at this time last year. But the blocking north of Alaska was pretty extreme. Just a month earlier we had the record 1068 mb high over the Arctic. So the pattern was primed for a record May Arctic outbreak here. The daily record low of 34° in NYC was the 3rd coldest on record for April. To put that in perspective, the last time NYC had a top 3 coldest monthly low temperature was way back in April and August 1982 and 1986. So I guess that it’s fitting the April 1982 blizzard set the standard for April blizzards and cold. The trace last May was a record shared with 1977 for latest in the season. 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 1891 32 0 2 1874 33 0 3 2020 34 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 Lowest Min Temperature Missing Count 1 1923 12 0 2 1874 20 0 3 1982 21 0 Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Aug Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 1986 50 0 - 1982 50 0 - 1976 50 0 - 1965 50 0 - 1885 50 0

You had to figure that a cooler trough would find a way to develop by later next week with a record MJO 8-1 for early May. The big question is how the individual storm details will work out with so much model spread. The models may not be much help beyond 3-5 days with such an amplified pattern. Big warm up next several days MJO 8-1 cool down by later in the week

Yeah, I have noticed this also. It seems to happen when the top of the mixed layer gets near 700mb. The peak wind gusts often run about 5 to 10 KT higher than strongest surface to 700mb level forecast sounding winds. The afternoon peak gusts around NYC occurred near the time of the convection moving through. The Manhattan Mesonet rooftop sensor gusted to 60 mph at 2:20 then had .01 of rain at 2:35. http://www.nysmesonet.org/weather/meteogram#network=nysm&stid=manh

8th warmest spring so far in NYC. So it’s no surprise to see the models indicating 80° potential for the warm spots on Sunday. 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 Apr 30 Missing Count 1 1945-04-30 53.3 0 2 2010-04-30 53.0 0 3 2012-04-30 52.8 0 4 1921-04-30 52.2 0 5 2016-04-30 51.1 0 6 1985-04-30 50.5 0 7 1903-04-30 50.3 0 8 2021-04-30 50.1 0 - 1977-04-30 50.1 0 - 1946-04-30 50.1 0 9 2002-04-30 50.0 0 - 1991-04-30 50.0 0 10 1973-04-30 49.8 0

A +2.5 to +3.5 March followed by a +1 to +2 April.

Jones Beach already gusting to 46 mph. Jones Beach N/A 61 N/A N/A NW35G46

NYC is currently at the 9th warmest March and April average temperature of 50.0°. 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 Apr 30 Missing Count 1 1945-04-30 53.3 0 2 2010-04-30 53.0 0 3 2012-04-30 52.8 0 4 1921-04-30 52.2 0 5 2016-04-30 51.1 0 6 1985-04-30 50.5 0 7 1903-04-30 50.3 0 8 1977-04-30 50.1 0 - 1946-04-30 50.1 0 9 2021-04-30 50.0 1 - 2002-04-30 50.0 0 - 1991-04-30 50.0 0 10 1973-04-30 49.8 0

Lapse rates really steepen next few hours. 45KT in the mixed layer should produce gusts to 50 mph + by later this afternoon. Then a 50KT LLJ arrives this evening with the potential for some peak gusts to around 60 mph.

I started a May 2021 thread.

Looks like some briefly cooler temperatures on May 1st with morning low 40s around NYC. Then a quick rebound in temperatures back to the 70s on Sunday.

While the forecast soundings are indicating only modest CAPE, the seasonally high PWATS signal the chance for some much needed rainfall. Maybe some locally strong to severe storms if we can destabilize more than forecast with the decent shear. But most will be happy to get a soaking downpour.

Looks like our first +3 SD MJO phase 8 since February 2017. That one was preceded by the blizzard of 2017. But much warmer conditions and a spring wavelength response didn’t allow for a similar wintery outcome. 2021 4 27 -2.8350327 1.1143280 8 3.0461676 2017 2 15 -3.0841775 0.94387865 8 3.2253771 https://www.weather.gov/okx/Blizzard_Feb92017

Just looking at the teleconnections, it appears like this should have been a cold April. But the warmer south based blocking continued like we saw during the winter. So it was a rare warmer than average -EPO, -AO, -NAO April.

This is one of the less common months when the high temperatures are driving the departures. NYC was +1.5 on the max and +0.3 on the min through yesterday. Frequent cold fronts and drier conditions have allowed the minimum temperatures to remain near normal while the high temperatures have been above average. CLIMATE REPORT NATIONAL WEATHER SERVICE NEW YORK, NY 435 PM EDT WED APR 28 2021 ................................... ...THE NEWARK NJ CLIMATE SUMMARY FOR APRIL 28 2021... VALID TODAY AS OF 0400 PM LOCAL TIME. CLIMATE NORMAL PERIOD 1981 TO 2010 CLIMATE RECORD PERIOD 1893 TO 2021 WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST VALUE (LST) VALUE VALUE FROM YEAR NORMAL ................................................................... TEMPERATURE (F) TODAY MAXIMUM 89 157 PM 90 1990 67 22 68 2009 MINIMUM 50 502 AM 33 1934 48 2 40 AVERAGE 70 57 13 54

Yeah, now the temperature is back down to 71° at LGA. Very impressive hourly and daily temperature jumps since late March on the wind shifts. The temperature on the South Shore back in late March rose from 57° to 80° in an hour.

Today was the 7th highest April diurnal temperature range for Newark at 38°.

When was the last time that Newark was 17° warmer than LGA at 2pm? Newark/Liberty PTSUNNY 88 53 30 SW14G21 LaGuardia Arpt PTSUNNY 71 46 40 NE9

Temperatures are off to the races for areas that get into a westerly flow like we are first seeing in Central New Jersey. WRI just experienced a 25° jump in just 3 hours. So our local spots that can go more westerly will quickly rise into the 80s.

This month is another example of the coldest departures focused around the Plains.

Looks like .47 so far in NYC. Matches the spring theme of mostly light to moderate events. While this spring is on the drier side of recent years, it’s still wetter than 2016 was. Time Series Summary for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Ending Date Total Precipitation Mar 1 to Apr 25 Missing Count 2021-04-25 5.88 0 2020-04-25 7.33 0 2019-04-25 7.26 0 2018-04-25 10.62 0 2017-04-25 8.69 0 2016-04-25 2.49 0 2015-04-25 6.80 0 2014-04-25 5.60 0 2013-04-25 4.17 0 2012-04-25 4.45 0 2011-04-25 11.23 0 2010-04-25 12.94 0

The system is moving pretty quickly. So the best chance for rain will be tonight into early Sunday. Looks like the afternoon could turn out nice with breaks of sun and 60s. KEWR GFS MOS GUIDANCE 4/24/2021 0600 UTC DT /APR 24 /APR 25 /APR 26 / HR 12 15 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18 00 06 X/N 71 51 63 41 65 TMP 53 64 68 68 64 58 54 53 54 54 59 61 56 53 48 43 46 55 62 59 47 DPT 36 32 30 31 33 36 40 42 44 44 43 38 34 33 30 26 24 19 17 19 25 CLD SC FW SC BK OV OV OV OV OV OV OV BK FW CL CL CL CL FW CL FW CL WDR 26 27 23 20 22 18 18 05 02 36 31 31 30 31 29 29 30 31 30 30 30 WSP 05 07 10 11 09 05 03 05 09 12 14 17 19 19 15 14 17 17 18 18 04

Quick wavelength changes coming up with the very strong MJO and typhoon recurve. Looks like we finally get our April 80° potential on Wednesday. But a near record amplitude MJO 8 for April doesn’t allow it to lock in for long. So it’s followed by a backdoor cold front and cooler on Thursday.