bluewave

Tuesday looks like it could be the 3rd 95° day of the season so far. Very warm WNW flow ahead of the backdoor. Quite a difference between our area and New Hampshire. JFK could beat the record high of 92° set in 1988. Data for May 31 - JFK INTERNATIONAL AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature Precipitation Snowfall Snow Depth 1988-05-31 92 65 0.00 0.0 0 1991-05-31 91 69 1.08 0.0 0 1986-05-31 91 69 0.01 0.0 0

It’s been tough to get a completely dry Memorial Day weekend with an official 90° heatwave covering all 3 days. The last time this happened was back in 1999. This was followed by one of our hottest July 4th weekends. Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature Precipitation 1999-05-29 90 62 0.00 1999-05-30 90 63 0.00 1999-05-31 90 64 0.00 Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature Precipitation 1999-07-03 88 73 0.00 1999-07-04 99 79 T 1999-07-05 103 81 0.00

I started the June thread for anyone that wants to discuss the extended pattern,

Looks like June will start out with a blocking pattern. So probably near seasonable temperatures. We’ll have to wait a while for extended 90° heat which has been coming in 1 or 2 day intervals this spring.

It gave us another over the top warm month. Our area is running +1 to +2 for June. New England is +3 to +5.

Unusual amount of amplitude to our blocking and MJO waves heading into early June. So we get a few days in the 90s followed by back door cold fronts with high pressure building into New England. Record SE Canada block for May has been pumping the high pressure over New England.

Yeah, the backdoor comes through later on Tuesday with cooler SE flow for Long Island on Wednesday.

The highs on Saturday topped out in the low 70s from Long Beach to Fire Island. The 90°s didn’t start until you got to near or just north of the Southern State. Pretty typical for strong sea breeze days. Tuesday could be a rare westerly flow heat event for us. So probably the first 90s of the season for JFK. The record high is 92° set back in 1988. Models have 850 temperatures around +20c with westerly flow through early afternoon..The timing of the backdoor cold front will be key as to how high into the 90s we make it.

It may be related to the coarse model resolution unable to pick up where the actual sea breeze front is located. The Euro had low 90s near Commack on Saturday. But it missed the 90° at ISP. It will be interesting to see how the model performs when they increase the resolution to around 4km in the coming years. One of the features of the raw Euro 2m forecast is that it sometimes limits the 90° temperatures to Monmouth County like it has on Monday. But when the flow is SW, those 90° readings often end up expanding north from EWR to LGA and the North Shore. The mid 90s it forecast for CNJ on Saturday made it up to EWR and Central Queens. The raw ECMWF also has too much of an onshore flow bias at Newark . The NWS MDL lab used to generate ECMWF MOS. So it corrected the raw 2m and wind direction biases. Similar to the GFS and NAM MOS. I am not sure if they still have that on their AWIPS terminals. Most model raw 2m temperature forecasts are too cool when there is strong WAA and full sun away from the immediate sea breeze. So we can get a better idea of the high temperature potential from the 850mb temperatures. The future of all modeling may be machine learning automatically correcting model biases beyond what the current MOS does. So in the meantime, we have to try and adjust the models manually to correct their known biases.

Memorial Day may make a run on 90° in the usual warm spots.

Yeah, the extension of the ridge into SE Canada has been pushing extreme severe storms further north than usual for this time of year.

The benchmark for early June heat in our area was 2011 when the Newark suburbs hit 103°. Data for June 1, 2011 through June 10, 2011 Click column heading to sort ascending, click again to sort descending. State Name Station Type Highest Max Temperature NJ CANOE BROOK COOP 103 NJ NEWARK LIBERTY INTL AP WBAN 102 NJ TETERBORO AIRPORT WBAN 101 NJ HARRISON COOP 99 NY BRONX COOP 97 NY LAGUARDIA AIRPORT WBAN 97 NJ CALDWELL ESSEX COUNTY AP WBAN 97 NY PORT JERVIS COOP 96 NJ PLAINFIELD COOP 96 NY MINEOLA COOP 96 NY WEST POINT COOP 95 NY NY CITY CENTRAL PARK WBAN 95

Memorial Day weekend is on track to follow the post 15-16 super El Niño script. At least one day with rainfall. Best chance for rain this year appears to be on Saturday with improvement by Sunday or Monday. Memorial Day weekends at Newark with Memorial Day bolded Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Date Max Temperature Precipitation 2021-05-29 52 0.58 2021-05-30 53 1.15 2021-05-31 76 T Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Date Max Temperature Precipitation 2020-05-23 71 0.79 2020-05-24 68 T 2020-05-25 73 T Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Date Max Temperature Precipitation 2019-05-25 70 0.00 2019-05-26 90 0.20 2019-05-27 82 0.00 Go Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Date Max Temperature Precipitation 2018-05-26 92 0.00 2018-05-27 78 0.87 2018-05-28 71 0.00 Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Date Max Temperature Precipitation 2017-05-27 74 0.00 2017-05-28 71 T 2017-05-29 61 0.14 Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Date Max Temperature Precipitation 2016-05-28 96 0.00 2016-05-29 88 0.03 2016-05-30 83 1.57

The reason is that models struggle with closed lows in these blocky patterns. They all seem to agree on rain from Friday into Saturday. The 12z Euro gets the front to our east by later Saturday. So a backloaded Memorial Day weekend with Sunday and Monday better than Friday and Saturday.

This May is just an extension of recent summers since 2018 with record blocking in SE Canada. Over the top warm ups are common in this pattern like we saw a few weeks ago with the record heat in Northern New England. Then we get intervals with the ridge flattening out like this past weekend. So places away from the sea breeze make a run on record highs. But the deep westerly flow heat events that make it to JFK like we saw from 2010 to 2013 are absent. Then there is the occasional cutoff low getting stuck underneath the block. So a fairly predictable pattern. May 2022 Summers since 2018

The actual SSTs are still In the upper 50s which will give you a very cool sea breeze. So around 20° colder than the recent summers with SSTs pushing 80° at times. But the departures relative to average are the warmest on record for this time year in the North Atlantic.

Yeah, the expansion of the ridge into New England allows warmer S to W flow away from the immediate shore. We have the cooler onshore flow influence. It’s exaggerated in May since the SSTs are still so cold. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=71&network=VT_ASOS&zstation=BTV&year=2022&month=5&units=MPH&_r=t&dpi=100&_fmt=png

These over the top type warm ups have become very common in recent years. It has allowed Concord, New Hampshire to pull ahead of Newark for the the first 90° day of the year. The average first 90° of the season at Concord has moved up from June 5th in 1981 to May 17th in 2022. Newark has remained nearly unchanged at May 21st in 1981 and May 20th in 2022.

The dew points have been running above average with the persistent onshore flow. It has also kept our departures cooler than New England. The stronger high pressure to our north has allowed for higher departures in New England. This has become a common theme in recent years with more over the top warmth. The forecast for the rest of this month is similar. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=76&network=NY_ASOS&station=JFK&season=may&varname=dwpf&year=1893&w=bar&hours=0-23&_r=t&dpi=100&_fmt=png Warmer in New England this month BTV….+4.2 BDL….+3.7 EWR….+2.1……further inland from the marine influence near the coast NYC….+0.3 LGA….-0.1…..cool easterly flow off the Long Island sound Forecast for the rest of the month more of the same

This month is on track to finish as one of the most persistent onshore flow Mays. High pressure has been dominating in New England all month. The warm up this weekend favored areas away from immediate sea breeze for the highest temperatures. This week will feature a return of high pressure to our north and easterly flow. Next surge of warmth looks to be on track for around Memorial Day. It could be an over the top warm up with higher temperatures in New England. But small details like that are tough to work out too far in advance. Models have a round of blocking in early June. So the next warm up at the end of May will get pushback from high pressure to our north again. Similar to what we have been experiencing recently. May pressure pattern Forecasts into early June

The hottest parts of the region yesterday were Philly, NNJ, and Queens all reaching 95°+. Models did very well showing the maximum temperatures for the whole area in NJ. Some models did better showing the 90° readings near ISP. Most struggled with the heat in Central Queens showing too much cooling sea breeze in Corona, Queens. The wind forecast at EWR was also very hard for the models to resolve. We were discussing this with Forky earlier in the thread. Models show too much onshore flow at Newark. All the models did very well showing the 60s to low 70s for the South Shore beaches. More struggles for the NYC high temperature. This is a result of the tree growth blocking the sensor. But the raw model guidance doesn’t know that this is the case. So the NWS and several TV outlets went for a high of 93° which verified as 90°. This is in line with some of my posts in the climate change thread. The trees can shave off around 3° from the highs from what they should be out in the open in an area like the Great Lawn. Sometimes the difference can be a little higher or a little lower. This is probably a result of the moisture content in the vegetation. Monthly Data for May 2022 for Upton NY NWS CWA Click column heading to sort ascending, click again to sort descending. State Name Station Type Highest Max Temperature NJ TETERBORO AIRPORT WBAN 98 NJ NEWARK LIBERTY INTL AP WBAN 95 NJ CALDWELL ESSEX COUNTY AP WBAN 95 Fresh Kills 95 Corona 95 Monthly Data for May 2022 for Mount Holly NJ NWS CWA Click column heading to sort ascending, click again to sort descending. State Name Station Type Highest Max Temperature NJ SOUTH JERSEY REGIONAL AIRPORT WBAN 95 DE GEORGETOWN-DELAWARE COASTAL AIRPORT WBAN 95 PA PHILADELPHIA INTL AP WBAN 95

That’s a result of the ASOS being improperly located under dense vegetation. It’s common for NYC to try and play catch up when the sun dries wet morning vegetation. But NYC ultimately fell 3° short of the NWS official forecast high of 93°. I don’t think that the NWS applies any deep shade correction to their forecast for NYC. That’s why they usually do much better with their forecasts for the other sites than Central Park. Official NWS high temperature forecasts for today on the left Actual NYC high temperature below CLIMATE REPORT NATIONAL WEATHER SERVICE NEW YORK, NY 431 PM EDT SAT MAY 21 2022 ................................... ...THE CENTRAL PARK NY CLIMATE SUMMARY FOR MAY 21 2022... VALID TODAY AS OF 0400 PM LOCAL TIME. CLIMATE NORMAL PERIOD 1991 TO 2020 CLIMATE RECORD PERIOD 1869 TO 2022 WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST VALUE (LST) VALUE VALUE FROM YEAR NORMAL ................................................................... TEMPERATURE (F) TODAY MAXIMUM 90 223 PM 93 1996 73 17 79

Elongation of the ridge to the east of New England in recent years has been causing more frequent onshore flow. Notice how much flatter the ridge was back in May 1996. So it allowed a deep westerly flow from the Midwest right out across Long Island.

The heat index at Newark today was the highest in May since 1996. Came within a few degrees of the all-time highest May record of 102°. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=155&network=NJ_ASOS&zstation=EWR&var=max_feel&threshold=100&hour=12&sdate=2000%2F01%2F01&edate=2000%2F12%2F31&month=may&_r=t&dpi=100&_fmt=png

Wantagh just dropped from 85° to 70° in 1 hour. https://www2.nysmesonet.org/weather/meteogram#network=nysm&stid=want