bluewave

Yeah, NYC used to warmer than LGA during the summer in the 70s and earlier before the excess tree growth. https://www.nytimes.com/1977/07/22/archives/vandals-in-central-park-forcing-weather-service-to-seek-new-site.html Harold Gibson, the meteorologist in charge of the New York bureau, When the devices at the castle are not functioning, the Weather Service substitutes readings from La Guardia Airport. But Mr. Gibson said those readings do not really reflect conditions in the city, because they may be several degrees cooler in summer or warmer in winter than those in Central Park. NYC is the only station with the same number of 90° days in the recent era as the 70s due to tree growth too close to sensor. It used to have more 90° days than LGA and 3 less than EWR. Now it’s 7 fewer days than LGA and 14 lower than Newark. Monthly Number of Days Max Temperature >= 90 for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Apr May Jun Jul Aug Sep Oct Season Mean 0 1 2 7 6 2 0 18 1970 0 2 1 4 8 7 0 22 1971 0 0 5 6 5 2 0 18 1972 0 0 0 11 3 1 0 15 1973 0 0 4 4 6 4 0 18 1974 0 1 1 10 5 0 0 17 1975 0 1 1 2 4 0 0 8 1976 3 0 6 2 4 0 0 15 1977 1 2 0 11 7 2 0 23 1978 0 1 2 3 5 0 0 11 1979 0 2 0 7 8 1 0 18 1980 0 2 1 11 15 3 0 32 Monthly Number of Days Max Temperature >= 90 for LAGUARDIA AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Year Apr May Jun Jul Aug Sep Oct Season Mean 0 1 2 5 4 1 0 13 1970 0 2 1 5 9 5 0 22 1971 0 0 3 3 2 1 0 9 1972 0 0 0 3 0 1 0 4 1973 0 0 3 3 7 4 0 17 1974 0 1 1 9 2 0 0 13 1975 0 1 1 2 3 0 0 7 1976 1 0 5 1 3 0 0 10 1977 0 1 0 9 3 1 0 14 1978 0 0 0 3 1 0 0 4 1979 0 2 0 7 7 0 0 16 1980 0 0 3 8 9 2 0 22 Monthly Number of Days Max Temperature >= 90 for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Year Apr May Jun Jul Aug Sep Oct Season Mean 0 1 3 8 7 2 0 21 1970 0 2 2 5 8 5 0 22 1971 0 0 6 7 7 2 0 22 1972 0 0 0 16 4 1 0 21 1973 0 0 5 9 12 5 0 31 1974 1 2 2 10 3 0 0 18 1975 0 1 3 3 5 0 0 12 1976 2 0 7 2 4 0 0 15 1977 1 3 1 14 6 1 0 26 1978 0 1 3 8 4 0 0 16 1979 0 2 1 8 9 0 0 20 1980 0 1 3 8 12 3 0 27 Monthly Number of Days Max Temperature >= 90 for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Apr May Jun Jul Aug Sep Oct Season Mean 0 1 3 8 5 2 0 18 2012 0 0 5 10 3 1 0 19 2013 0 2 3 10 1 1 0 17 2014 0 0 0 3 3 2 0 8 2015 0 0 1 5 8 6 0 20 2016 0 2 0 10 7 3 0 22 2017 0 3 3 5 1 1 0 13 2018 0 2 3 6 7 3 0 21 2019 0 0 1 10 3 0 1 15 2020 0 0 2 14 4 0 0 20 2021 0 0 8 4 5 0 0 17 2022 0 2 1 10 11 1 0 25 Monthly Number of Days Max Temperature >= 90 for LAGUARDIA AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Year Apr May Jun Jul Aug Sep Oct Season Mean 0 2 4 11 7 2 0 25 2012 0 2 6 14 6 0 0 28 2013 0 2 2 15 1 1 0 21 2014 0 0 0 3 1 2 0 6 2015 0 0 3 6 8 3 0 20 2016 0 3 1 15 10 3 0 32 2017 0 3 3 8 2 1 0 17 2018 0 4 4 10 16 4 0 38 2019 0 0 4 14 5 2 1 26 2020 0 0 5 19 10 0 0 34 2021 0 0 9 8 8 0 0 25 2022 0 3 3 11 13 0 0 30 Monthly Number of Days Max Temperature >= 90 for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Year Apr May Jun Jul Aug Sep Oct Season Mean 0 2 5 13 9 3 0 32 2012 0 2 6 16 7 2 0 33 2013 0 2 4 15 3 1 0 25 2014 0 0 2 8 2 3 0 15 2015 0 2 4 11 13 5 0 35 2016 0 3 3 16 13 5 0 40 2017 0 3 5 9 2 3 0 22 2018 0 4 5 9 14 4 0 36 2019 0 1 4 14 4 3 1 27 2020 0 0 5 17 9 0 0 31 2021 0 4 12 11 13 1 0 41 2022 0 4 6 20 18 1 0 49

Already 90° in SE CT. Chester FAIR 90 43 19 N6

I don’t think so.The closest NYC came was within 5 days during April 1976. Walpack did it within 2 days this week. Have to go out West for 90° days that start below freezing. https://www.wunderground.com/cat6/extreme-short-duration-temperature-changes-us Data for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature 1976-04-12 43 25 1976-04-13 62 36 1976-04-14 72 48 1976-04-15 76 53 1976-04-16 82 56 1976-04-17 91 66 1976-04-18 96 70 1976-04-19 92 68 ▼ Walpack NJ 2023-04-13 SafetyNet 91 41 29.93 29.81 0.00 16 ▼ Walpack NJ 2023-04-12 SafetyNet 83 48 29.94 29.81 0.00 20 ▼ Walpack NJ 2023-04-11 SafetyNet 76 27 30.29 29.94 0.00 20 ▼ Walpack NJ 2023-04-10 SafetyNet 70 23 30.49 30.29 0.00 11 ▼ Walpack NJ 2023-04-09 SafetyNet 60 20 30.51

I guess part of the problem is that people were doubting the strength based on the previous winter forecast being so far off. Also never had a 2nd year El Niño super event since 1950. We technically got some Modoki-like west based forcing with the biggest snowstorm on record in NYC during January. Then the first below 0° since 1994.

https://threadex.rcc-acis.org NYC recorded only 2 daily record daily high temperatures since 2015 in JJA with all the extra tree growth over the sensor. Poughkeepsie is at 10 record daily highs since 2015. Newark has 10 also since 2015 during the summer. With bare trees during the winter, NYC has had 15 record highs DJF. There were 21 record highs at Poughkeepsie. With 16 winter record highs at Newark. So NYC has had 4 daily record highs this year so far. That is 4 times more than when the trees were fully leafed out in the summer since 2015.

Yeah, the lower dewpoints this month allowed the minimum departures to remain much lower than the maximum departures.

That’s pretty impressive. While this data only goes back to 1998, it’s probably safe to say it’s a new record high in your area. https://xmacis.rcc-acis.org Almanac for MONTGOMERY ORANGE COUNTY AP, NY April 13, 2023 Daily Data Observed Normal Record Highest Record Lowest Max Temperature M 59 81 in 2018 45 in 2007 Min Temperature M 35 53 in 2002 24 in 2000 TEMPERATURE (F) TODAY MAXIMUM 90R 2:57 PM 88 1945 60 30 77 MINIMUM 48 5:43 AM 19 1986 37 11 38 AVERAGE 69 48 21 58

Made it before the trees had a chance to leaf out and block the sensor.

50° range today at Walpack. https://www.njweather.org/data/daily/79 Walpack NJ 2023-04-13 SafetyNet 91 41

We would expect the -PDO to weaken from these -2 values should the El Niño actually become strong. But even a neutral to -1 PDO with a moderate to strong El Niño could displace the Nino +PNA ridge over to the Northeast. These seasonal model forecasts don’t have that much long range skill. So the El Niño and PDO values will have to wait. Plus the models have really struggled with El Niño forecasts since 2012. 2012-2013 El Niño never developed due to strong -PDO and trades 2014-2015 El Niño much weaker than forecast 2015-2016 forecast was pretty good 2017-2018 El Niño was but forecast never developed 2018-2019 El Niño never coupled

Central Park tied the record of 88° before the trees fully leafed out.

Coastal sections of Northern California had their 2nd coldest March on record. I have been using NOAA. The coastal bouy off San Diego recorded its lowest SST on record. So the trades have been slow to relax back to the Central Pacific with this pattern. Notice how the WWBs are further west near Indonesia instead of closer to 180. So the subsurface near Dateline is much less impressive than years like 2015 and 1997 as GaWx posted yesterday. https://www.ncei.noaa.gov/access/monitoring/pdo/

ISP tied the record high of 82° at 10am. 4/13 82 in 1977 72 in 2018 72 in 1968

Don’t have that one. But NOAA came in at -2.35 for March. Lowest March reading since 1956. https://www.ncei.noaa.gov/pub/data/cmb/ersst/v5/index/ersst.v5.pdo.dat

25 inches of rain for Fort Lauderdale.

HRRR has 3rd earliest 90° for Newark.

Has Newark ever had a record low max which was above 60° in the spring with a dewpoint in the 20s before? The previous record low max of 59° in 2017 had a dewpoint of 51°. The record for 4-13 had a 60° dewpoint. So these record low maxes usually occur on higher dewpoints above 50° early mornings. Newark/Liberty CLOUDY 65 29 4/12 59 in 2017 56 in 1948 56 in 1947 6:51 AM 60 °F 51 °F 72 % 4/13 61 in 2019 6:51 AM 61 °F 60 °F 97 % 4/14 62 in 2014 6:51 AM 62 °F 55 °F 78 %

The last 35 dewpoint at Newark in July was in 2010. Plenty of dry heat that month. The drought feedback boosted the heat that month. https://www.wunderground.com/history/daily/us/nj/newark/KEWR/date/2010-7-1 4:51 PM 79 °F 35 °F 20 % https://www.wunderground.com/history/daily/us/nj/newark/KEWR/date/2010-7-3 2:51 PM 92 °F 41 °F 17 % https://www.wunderground.com/history/daily/us/nj/newark/KEWR/date/2010-7-4 2:51 PM 99 °F 43 °F 15 % https://www.wunderground.com/history/daily/us/nj/newark/KEWR/date/2010-7-5 1:51 PM 100 °F 45 °F 15 % https://www.wunderground.com/history/daily/us/nj/newark/KEWR/date/2010-7-6 12:51 PM 102 °F 56 °F 22 % Data for July 1, 2010 through July 30, 2010 Click column heading to sort ascending, click again to sort descending. State Name Station Type Highest Max Temperature NY MINEOLA COOP 108 NJ CANOE BROOK COOP 107 NY WANTAGH CEDAR CREEK COOP 107 NJ HARRISON COOP 106 NJ RINGWOOD COOP 106 NJ CRANFORD COOP 104 CT DANBURY COOP 104 NJ NEWARK LIBERTY INTL AP WBAN 103 NY LAGUARDIA AIRPORT WBAN 103 NY NY CITY CENTRAL PARK WBAN 103 NJ TETERBORO AIRPORT WBAN 103 NY WEST POINT COOP 103 NY SHIRLEY BROOKHAVEN AIRPORT WBAN 103 Data for July 1, 2010 through July 30, 2010 Click column heading to sort ascending, click again to sort descending. State Name Station Type Highest Max Temperature NJ SOMERDALE 4 SW COOP 106 PA MARCUS HOOK COOP 105 NJ NEW BRUNSWICK 3 SE COOP 105 NJ PENNSAUKEN 1N COOP 104 PA NORTHEAST PHILADELPHIA AIRPORT WBAN 104 NJ TRENTON-MERCER AIRPORT WBAN 104 NJ FREEHOLD-MARLBORO COOP 104 NJ SOUTH JERSEY REGIONAL AIRPORT WBAN 104

Newark ties with 1977 for 7th earliest 85° or warmer day of the season. First/Last Summary for NEWARK LIBERTY INTL AP, 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 First Value Last Value Difference 1-1990 03-13 (1990) 86 10-09 (1990) 87 209 2-1945 03-20 (1945) 85 09-29 (1945) 89 192 3-1998 03-30 (1998) 86 09-27 (1998) 91 180 4-1991 04-07 (1991) 85 09-17 (1991) 95 162 4-2010 04-07 (2010) 92 09-25 (2010) 90 170 5-2013 04-09 (2013) 85 10-04 (2013) 89 177 6-2011 04-11 (2011) 87 10-10 (2011) 85 181 7-1977 04-12 (1977) 90 09-18 (1977) 85 158

I learned more about weather forecasting using resources on the internet than trying to use textbooks and Alden Difax maps in the 1980s. You don’t even need to understand calculus to be a good forecaster these days. But an advanced math background is required if you want to work in model development or other research areas and academia. Though you can still understand the concepts in papers without advanced math. A big part of forecasting is understanding model strengths, weaknesses, and biases. Learning basic weather statistics can go a long way.

None of the El Niño events following 09-10 evolved in a way that were familiar to us from what happened in the past. Models were indicating an El Niño in 12-13 that began to dissipate after Labor Day with the strong trades and -PDO. But it still acted in some ways like like an El Niño winter. Front loaded warmth and the historic Nemo in February. The spring of 2014 saw strong WWBs and the talk turned to a strong El Niño in 14-15. But the trades picked back up and we had one of the farthest west Modokis for that winter. The big event was delayed a year to 15-16 and produced the record Nino 4 temperatures. Front loaded historic warmth with the first strong MJO 4-6 in December during a super El Niño. But the westward lean back to the CP during the 2nd half of the winter with blocking gave us the historic January snowstorm. The 18-19 El Niño never coupled due to all the warm water in the WPAC mimicking a La Niña. So we got the Aleutian Ridge-Western Trough-SE Ridge combo. This event is starting out east based before Nino 3.4 had a chance to catch up. So we could see Nino 1-2 begin to decline before an actual El Niño is declared using 3.4. Not many analogs for what happens when these two regions are out of phase. We will probably need much stronger and sustained CP WWBs to get a trimonthly ONI of +1.5 or higher in Nino 3.4. This could happen if the trades can relax enough. But we have never seen a super before with such strong trades like we had in March. Seems like the atmosphere gets an early start in March ahead of super El Niño’s. But some strong events can see a pick up in WWB activity later in the spring. So these individual model forecasts may not yet have a good handle of how this El Niño will develop until the CP WWB activity comes into better focus.

This link gives you a very good explanation. I can remember my class learning the Skew-T back in meteorology 101. Gives a great image of the whole atmosphere in one diagram. http://www.theweatherprediction.com/thermo/skewt/

Yeah, true east based El Niño events have become very rare since the 1980s. The 82-83 and 97-98 events developed with strong WWBs in the CPAC in March. That didn’t happen this year. So we haven’t had strong east based event developing from the rare EPAC WWBs like we recently saw. That’s why we don’t have any good analogs for how this one may evolve.

Pretty cool soundings.