bluewave

At least some measurable rainfall which was the case going back to March 1st.

We are back to the rain on weekends theme since March 1st after a brief break.

The only preseason metric which has worked for all La Ninas since 2010 has been the October early MJO indicator. This has helped out with the snowfall potential. But every La Niña since 11-12 has been warmer than average here in the Northeast.

We are probably better off using the SSTs west of the Dateline in the tropics and subtropics rather than what is happening in the official Nino regions. It seems to me the WPAC warm pool has been driving the bus since 15-16. The RONI has been trying to do this but it still feels incomplete to me. Since the MJO in the 4-7 regions has become so dominant regardless of El Niño, La Niña, or neutral.

After the really comfortable dew points on Friday ,we are headed for our first mid 70s dew points of the season on Sunday. This will push the HX into the upper 90s in NJ. Some spots may approach a 100 HX.

It looks like the -PDO has been driving the strong La Niña background state with the 100° June heat we have just seen in the East. As the actual La Niña has been slower out of the gate than usual. May be related to the ongoing record marine heatwaves slowing the drop in SSTs east of the Dateline. But as long as the -PDO is so negative, we are getting a very strong La Niña background state regardless of what happens east of the Dateline. Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of Jun Click column heading to sort ascending, click again to sort descending. 1 2021 103 La Niña 2 2011 102 La Niña - 1994 102 El Niño - 1993 102 Neutral - 1952 102 Neutral - 1943 102 7 1988 101 El Niño to La Niña - 1966 101 El Niño to La Niña 9 2024 100 El Nino to La Niña - 1959 100 El Niño to neutral - 1953 100 El Niño - 1934 100

The best the PDO has been able to do has been a rise back to around -1.5 before dropping again to the -2 to -3 range.

It felt great today. Quick turnaround for weekend with parts of area challenging the all-time PWAT record for June near 2.5”.

The record breaking 500 mb heights and surface high pressures just keep coming out there.

You can see how the tree growth is getting even thicker over the NYC ASOS as it couldn’t even make it to 95° during the big heatwave. Monthly Data for June 2024 for Upton NY NWS CWA Click column heading to sort ascending, click again to sort descending. NJ NEWARK LIBERTY INTL AP WBAN 100 NJ HARRISON COOP 100 NJ TETERBORO AIRPORT COOP 97 NY LAGUARDIA AIRPORT WBAN 97 NJ TETERBORO AIRPORT WBAN 97 NJ CALDWELL ESSEX COUNTY AP WBAN 97 NY WEST POINT COOP 96 NY PORT JERVIS COOP 96 CT MERIDEN MARKHAM MUNICIPAL AP WBAN 96 CT NORWICH PUBLIC UTILITY PLANT COOP 95 NJ CHARLOTTEBURG RESERVOIR COOP 94 NY NY CITY CENTRAL PARK WBAN 94 Corona, Queens…………………………………………………..98 Astoria, Queens…………………………………………………..97 Fresh Kills, Staten Island……………………………………..99 Hillsborough-Duke Somerset………………………………100 NYC was much closer to Newark during past 100° Junes at Newark before the tree issues began to really be a factor after the 1990s ASOS change. Monthly Data for June 1988 for Upton NY NWS CWA Click column heading to sort ascending, click again to sort descending. NJ NEWARK LIBERTY INTL AP WBAN 101 NY MINEOLA COOP 101 NJ PLAINFIELD COOP 100 NY LAGUARDIA AIRPORT WBAN 99 NJ CRANFORD COOP 98 NJ CANOE BROOK COOP 98 NY NEW YORK AVE V BROOKLYN COOP 98 NY NY CITY CENTRAL PARK WBAN 98 Monthly Data for June 1966 for Upton NY NWS CWA Click column heading to sort ascending, click again to sort descending. NJ NEWARK LIBERTY INTL AP WBAN 101 NY NY CITY CENTRAL PARK WBAN 101 NJ PATERSON COOP 101 NJ LITTLE FALLS COOP 100 NJ PLAINFIELD COOP 99 NJ ELIZABETH COOP 98 NJ JERSEY CITY COOP 98 NJ CANOE BROOK COOP 98 NY SCARSDALE COOP 98 NY WEST POINT COOP 98 Monthly Data for June 1952 for Upton NY NWS CWA Click column heading to sort ascending, click again to sort descending. NJ ELIZABETH COOP 103 NJ PATERSON COOP 103 NJ NEWARK LIBERTY INTL AP WBAN 102 NJ CANOE BROOK COOP 102 NY NEW YORK LAUREL HILL COOP 102 NY WEST POINT COOP 102 CT STAMFORD COOP 102 NJ PLAINFIELD COOP 101 NY LAGUARDIA AIRPORT WBAN 101 NJ RIDGEFIELD COOP 101 NJ LITTLE FALLS COOP 101 NY SUFFERN 2 E COOP 101 NY MINEOLA COOP 101 CT WATERBURY ANACONDA COOP 101 NJ JERSEY CITY COOP 100 NY NEW YORK BENSONHURST COOP 100 NY NY CITY CENTRAL PARK WBAN 100 Monthly Data for June 1943 for Upton NY NWS CWA Click column heading to sort ascending, click again to sort descending. CT DANBURY COOP 105 NJ NEWARK LIBERTY INTL AP WBAN 102 NJ CANOE BROOK COOP 102 NY PORT JERVIS COOP 100 NJ ELIZABETH COOP 100 NJ RIDGEFIELD COOP 100 NY BEDFORD HILLS COOP 100 CT BALTIC COOP 100 NJ PLAINFIELD COOP 99 NY LAGUARDIA AIRPORT WBAN 99 NY NY CITY CENTRAL PARK WBAN 99 Monthly Data for June 1934 for Upton NY NWS CWA Click column heading to sort ascending, click again to sort descending. NY MOUNT VERNON COOP 101 NJ PLAINFIELD COOP 101 NY NY CITY CENTRAL PARK WBAN 101 CT WATERBURY ANACONDA COOP 101 CT WATERBURY CITY HALL COOP 101 NJ JERSEY CITY COOP 100 NJ NEWARK LIBERTY INTL AP WBAN 100 NY FLUSHING COOP 100 NJ LITTLE FALLS COOP 100

Aerosols have been masking global warming over the years. But they have no idea how much since each model gives them a different answer. In addition to shipping places like China have cleaned up the sulphur emissions also. I think the scientific community is pretty much scrambling to figure out why the temperature increase was so much beyond expectations in recent years. Clouds and aerosols are very uncertain since the models have such a wide range of results.

It’s possible that the rapid reduction of shipping aerosols due to the new regulations that went into effect in 2020 is boosting the marine heatwaves in the mid-latitudes. One of these record marine heatwaves is driving the record SSTs east of Japan leading to the record -PDO values. The ongoing record marine heatwave in the Atlantic are driving the record +AMO. We will probably need further studies to confirm the exact reason for this sudden global temperature rise above model forecasts in recent years. But one of the uncertainties in climate modeling is how changes in clouds and aerosols affect global climate sensitivity to CO2 forcing.

While you are technically correct, the 18-19 El Niño wasn’t able to couple for much of the winter. So we effectively didn’t have an El Niño between 15-16 and 23-24. The La Niña background state is getting so strong, that we need a borderline super to actual super El Niño in order to couple with the 500 mb pattern. Plus the record MJO 4-6 in December 2015 and throughout the 23-24 event were more typical for La Ninas before this 10 year period. So even 2 such strong events couldn’t mute the WPAC warm pool influence. https://www.climate.gov/news-features/blogs/enso/csi-enso-case-missing-central-pacific-rainfall

June is our most recent to 10 warmest month around the region. This will be the 53rd top 10 warmest for spots since 2010. The only top 10 coldest month was February 2015.

My guess is that the major global temperature spike since the 14-15 super El Niño shifted the Pacific to this new state we have been seeing with record MJO 4-6 action in the Tropical West Pacific and record SSTs from Japan to north of Hawaii in the subtropics. This pattern has been driving the record winter warmth. It’s interesting how this period was preceded by the 13-14 and 14-15 winters which only lasted a few years before this much longer 9 year pattern so far. https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2022GL101078 The fundamental result of this study is that the first EOF of SST in the North Pacific has changed starting in 2014. For more than 20 years, the PDO has been used to describe the state of the North Pacific. However, since the marine heatwave of 2014, there have been remarkable changes to the dominant mode of SST in the North Pacific. The spatial pattern of the first EOF of SST from 1950 to 2021 is notably different from the PDO, suggesting that though the PDO served as a useful metric of SST variations until 2014 (Johnstone & Mantua, 2014), it may no longer be as effective a climate index for the North Pacific. From 1950 until the 2014 MHW, the first EOF remained consistent in its proportion of positive and negative regions with both taking up roughly half the area of the North Pacific (and with the positive region taken to be the eastern Pacific). When EOFs are calculated from 1950 to endpoints after 2014, the first EOF has a maximum positive region covering 77% of the North Pacific, with a PC indicating the largest anomalies on record. These changes to the first EOF/PC of North Pacific SST are nothing short of remarkable. In concert with these changes, the second EOF/PC of SST has also undergone profound evolution since 2014. This second EOF now accounts for approximately 18% of the variability, growing from 13% during the 1950–2013 period. The spatial structure of the second EOF now is positive over almost the entire basin, with a PC that has grown strongly positive in the last several years. Thus, the second EOF/PC describes warming over much of the Pacific not in the positive lobe of the first.

More of a gradient pattern over the next week. The major 95°+ heat shifts to the south with a possible brief return around Sunday. Then we wait and see what the pattern does as we head into July. It generally looks like heat will build to our SW and come NE from time to time before we get breaks from storms and fronts dropping south from Canada. So it looks like the rainfall pattern will continue to favor the more northern areas as the drought continues to expand over the Southeast and Mid-Atlantic. Newark and NJ had record warmth over the last week with 5 days going over 95°. Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. 2024-06-20 97 71 2024-06-21 100 77 2024-06-22 95 77 2024-06-23 99 75 2024-06-24 84 73 2024-06-25 94 66 2024-06-26 98 72 No surprise that this was the warmest June 20th to 27th on record for Newark and it beat the 2010 Nino to La Niña transition. Time Series Summary for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. 1 2024-06-27 84.1 1 2 1943-06-27 82.5 0 3 2010-06-27 81.9 0 4 1949-06-27 81.3 0 5 1997-06-27 79.9 0 Source region for the heat to our SW continues to dry out.

The 10 year average high at Newark in July has been 88.2°.So all it takes these days to reach 90° is a +1.8 max departure. Monthly Mean Max Temperature for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Mean 88.2 88.2 2023 89.1 89.1 2022 92.1 92.1 2021 87.5 87.5 2020 89.3 89.3 2019 89.5 89.5 2018 87.0 87.0 2017 85.5 85.5 2016 88.9 88.9 2015 87.5 87.5 2014 86.0 86.0 Monthly Number of Days Max Temperature >= 90 for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Mean 0 2 5 13 9 3 0 33 2023 2 1 1 14 5 6 0 29 2022 0 4 6 20 18 1 0 49 2021 0 4 12 11 13 1 0 41 2020 0 0 5 17 9 0 0 31 2019 0 1 4 14 4 3 1 27 2018 0 4 5 9 14 4 0 36 2017 0 3 5 9 2 3 0 22 2016 0 3 3 16 13 5 0 40 2015 0 2 4 11 13 5 0 35 2014 0 0 2 8 2 3 0 15

I like to focus on 95°+major heat since 90° days have really become commonplace in this much warmer climate. The new 10 year running average for Newark is around 33 days reaching 90° in a year. The last time Newark had under 10 days reaching 90° was way back in 1996.

Looks like our big June warm stretch is finally winding down as the warm spots should make it to the upper 90s today.

The HRRR also has a bowing line and possible MCS later.

Yeah, the GFS and Euro want to approach the highest June PWATS on record for this area around 2.5”. https://www.spc.noaa.gov/exper/soundingclimov2/

Several 100° readings in PA and NJ with this current heat wave as Reading had its 2nd warmest June high temperature on record. Monthly Data for June 2024 for Pennsylvania Click column heading to sort ascending, click again to sort descending. SHIPPENSBURG COOP 101 READING REGIONAL AIRPORT WBAN 101 Reading Area ThreadEx 101 BIGLERVILLE COOP 100 CONNELLSVILLE 2 SSW COOP 100 CARLISLE WATER PLANT COOP 100 NORTHEAST PHILADELPHIA AIRPORT WBAN 99 LANCASTER 2 NE FILT PLANT COOP 99 MIDDLETOWN HARRISBURG INT'L AP WBAN 99 HARRISBURG CAPITAL CITY AP WBAN 99 Middletown-Harrisburg Area ThreadEx 99 CASHTOWN 1S COOP 99 PHILADELPHIA INTL AP WBAN 98 YORK AIRPORT WBAN 98 LANCASTER AIRPORT WBAN 98 BLUE MARSH LAKE COOP 98 ALLENTOWN LEHIGH VALLEY INTERNATIONAL AIRPORT WBAN 98 SCHENLEY LOCK 5 COOP 98 WILLIAMSPORT REGIONAL AP WBAN 98 NEW HOLLAND 2 SE COOP 98 HERITAGE FIELD AIRPORT WBAN 98 SELINSGROVE 2 S COOP 98 Allentown Area ThreadEx 98 Williamsport Area ThreadEx 98 Philadelphia Area ThreadEx 98 Monthly Data for June 2024 for New Jersey Click column heading to sort ascending, click again to sort descending. Newark Area ThreadEx 100 NEWARK LIBERTY INTL AP WBAN 100 HARRISON COOP 100 SOUTH JERSEY REGIONAL AIRPORT WBAN 100 Time Series Summary for Reading Area, PA (ThreadEx) - Month of Jun Click column heading to sort ascending, click again to sort descending. 1 1952 102 0 2 2024 101 6 - 1925 101 0 - 1923 101 0 3 2021 99 0 - 1943 99 0 - 1934 99 0

The 12z run is much sunnier with highs pushing 100° in NJ before a MCS rolls through later in the day.

We have been fortunate that in this part of the country the most extreme warm temperature anomalies in the last decade have occurred during the cold season. Having 9 warmer to record warm winters in a row here is unprecedented in the climatological record. Our first +13 departure 50° December in 2015 was warmer than many Novembers. Plus our first winter 80° reading in February 2018 would have been the equivalent of around 112° had it occurred in a July. This isn’t to say that the summer warmth hasn’t been impressive since 15-16. This period has featured 7 out of 9 warmer summers with several ranking near the warmest on record. But the most extreme summer events have been the multiple 100 year to 1000 year rainfalls leading to serious flooding along with all -time rainfalls over shorter to longer intervals.

Yeah, it was a very impressive heatwave for June. My take on what caused the unprecedented talk were some of the social media posts showing the ECMWF model output. It has been running too warm recently and had highs for the heatwave in excess of 105° which would have been unprecedented this early in June. I was posting on this in the local NYC Metro forum and was skeptical of the model output since none of the other models were close. This was almost like a warm season version of what happened when model snowfall output for our region was posted on social media several winters ago. The NWS had to come out and say these amounts were unlikely but the heavy snowfall images gained traction and the talk began on social media. So we have been seeing more and more examples of unlikely raw model output getting onto social media and then getting picked up by others as if it was an actual likely outcome.