bluewave

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

65° along the South Shore beaches with the sea breeze after a high of 71°. https://mesowest.utah.edu/cgi-bin/droman/meso_base_dyn.cgi?stn=F3143&unit=0&timetype=GMT

The 71° dewpoint at SMQ could be the earliest on record. It’s currently the 4th highest on record for the month of May. Looks like their May record is 74°. Somerville SUNNY 80 71 https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=155&network=NJ_ASOS&zstation=SMQ&var=max_dwpf&threshold=100&hour=12&sdate=2000%2F01%2F01&edate=2000%2F12%2F31&month=may&_r=t&dpi=100&_fmt=png

The leaf transpiration on top of the NYC ASOS is doing its job. 1000 AM EDT SAT MAY 21 2022 CITY SKY/WX TMP DP RH WIND PRES REMARKS Central Park MOSUNNY 67 65 93 CALM 30.06F FOG LaGuardia Arpt PTSUNNY 70 64 81 NW6 30.02F Kennedy Intl MOSUNNY 72 66 81 NW8 30.03F HAZE Newark Liberty MOSUNNY 75 67 76 CALM 30.03S

With the dewpoint pooling along the sea breeze front today, we may be able to approach the highest dewpoint records for May.

The dense fog this morning was predicted by the models and we were discussing it. The HRRR forecast from yesterday is below showing the dense fog for this morning.

Starting the day with dense fog around the area. So a continuation of the marine influence theme. The higher dewpoints will help to boost the heat indices.

This was the heaviest downpour of the whole year so far here in SW Suffolk. But the winds were light. Best looking MCS structure in a while.

Impressive looking warned cell SW of Reading.

The RGEM looks more realistic into the same areas that have the tornado watch.

The forecasts soundings for Eastern PA would support tornadoes later.

This MCS looks like it will be more impressive than the storms on Monday were. http://www.meteo.psu.edu/fxg1/NAMSFC4_6z/rloop.html

The models haven’t been the greatest recently. So we have been seeing quite a bit of run to run variation. It may be related to the record La Niña for this time of year and developing -IOD.

The West becoming drier while the East gets wetter is part of the long term trend. So the precipitation response is different while the whole CONUS warms. Some studies show the drought spreading into the Plains in the future. But they are still wet in our area.

The warmth around Christmas has been more memorable than Memorial Day in recent years.

Still looks like too much wavelength volatility for any extended warm ups just yet.

Looks like this will be the 2nd year in a row with the weekend before Memorial Day being warmer. New run Old run