bluewave

Portions of Central NJ have already entered the top 10 for most 95° days and it’s only July 8th. Time Series Summary for HIGHTSTOWN 2 W, NJ - Jan through Dec Click column heading to sort ascending, click again to sort descending. 1 2002 17 0 2 1955 16 8 3 1953 14 0 4 2021 13 0 - 2018 13 1 - 2016 13 2 - 2010 13 4 - 1988 13 0 - 1949 13 0 5 2022 12 2 - 1999 12 0 - 1944 12 1 6 2020 11 0 - 1895 11 11 7 1983 10 0 - 1911 10 0 - 1894 10 12 8 2012 9 1 - 1966 9 0 - 1963 9 1 - 1929 9 2 9 2024 8 179 - 1957 8 0 - 1936 8 2 - 1933 8 19 - 1930 8 1 - 1910 8 0 - 1896 8 9

Warmest start to the summer in portions of Eastern PA. Time Series Summary for Reading Area, PA (ThreadEx) Click column heading to sort ascending, click again to sort descending. 1 2024-07-07 76.7 0 2 1925-07-07 75.9 0 3 1966-07-07 75.8 0 4 1943-07-07 75.5 0 5 1949-07-07 75.3 0 - 1934-07-07 75.3 0 6 2010-07-07 75.1 0 7 1952-07-07 74.9 0 8 1923-07-07 74.5 0 9 2005-07-07 74.4 0 10 1957-07-07 74.3 0 11 2021-07-07 74.2 0 - 2013-07-07 74.2 0 12 2008-07-07 74.1 0 13 2020-07-07 74.0 0 - 2011-07-07 74.0 0 - 1953-07-07 74.0 0 14 1921-07-07 73.8 0 - 1919-07-07 73.8 0 15 1901-07-07 73.6 0

The only time NYC can beat Newark these days is on an easterly flow which gives Newark a cooling bay breeze.

JFK needs westerly flow to reach 100°. Most of our heatwaves over the last decade have had too much southerly flow component due to the elongation of the subtropical ridge to the east of New England. It could also be that they moved the location of the ASOS back in the 1990s. Remember that JFK is the 9th largest airport in the U.S. at 8.1 sq miles. The current ASOS is located in a marshy area close to Woodmere in the 5 towns area of Long Island. The section of the airport closer to Ozone Park is at least 3-5° warmer. If the old weather station was located closer to that area it could also show another way JFK is getting more sea breeze influence in its readings.

JFK is approaching its longest under 100° streak due to all the high pressure east of New England with our heat waves resulting in more onshore flow. Number of Consecutive Days Max Temperature < 100 for JFK INTERNATIONAL AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Period of record: 1948-07-17 to 2024-07-07 1 4016 1999-07-06 through 2010-07-03 2 4009 1972-07-24 through 1983-07-15 3 4007 2013-07-19 through 2024-07-07 4 3610 1983-08-21 through 1993-07-08 5 2210 1966-07-05 through 1972-07-22 6 2185 1993-07-11 through 1999-07-04 7 963 1960-05-02 through 1962-12-20 8 857 1955-03-18 through 1957-07-21 9 817 1951-11-07 through 1954-01-31 10 736 1948-08-28 through 1950-09-02

That’s par for the course with the MJO since the convection which initiates the Rossby wave train can take up to 5-15days to propagate around the world to our area. But sometimes the conditions are such that other teleconnections are already in place which can coincide with the favorable phase and the effect is quicker. So it’s the combination of factors which determine the timing. https://journals.ametsoc.org/view/journals/clim/25/3/jcli-d-11-00033.1.xml The structure of the AO in the geopotential height and surface air temperature fields significantly varies based on the phase of the MJO; the AO index results in a preference for negative polarity in which the anomalously cold (warm) air is prevalent over the upper Midwest and New England (western United States) during the MJO phases 7–8 [convection over the Western Hemisphere; see L’Heureux and Higgins (2008)]. Lin et al. (2009) indicated that when MJO is detected in phases 6–8 (from the western Pacific to the Western Hemisphere), the NAO index is negative 5–15 days later, which can influence the weather in eastern North America and Europe. https://journals.ametsoc.org/view/journals/mwre/144/4/mwr-d-15-0434.1.xml These results are broadly consistent with Barrett et al. (2015). They found an increase in March snow depth for the 7 days following phases 6–8, which would equate well with the findings of our study, given the approximate time lag of 7 days per one phase of the MJO. Their findings also found no air temperature response, indicating that the increase in snowfall was driven by increased storminess and not by a decrease in melt rates. Our results verify this relationship by showing the concomitant modulation of extratropical cyclone activity. This study examined contemporaneous relationships between MJO phase and New England snowstorms. Thousands of kilometers separate these features, so we do not imply that the MJO’s effect is instantaneous. Rather, the MJO’s typical phase speed dictates that the MJO goes through one WH phase every 5–7 days, so some lag from the previous phase is implicit in our composites.

The snowstorm effect can be lagged following MJO 8-2 passages by sometimes 6-10 days after.

This is the warmest start to summer on record for parts of the region. Time Series Summary for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. 1 1994-07-07 78.5 0 2 2024-07-07 77.9 0 3 2010-07-07 77.4 0 4 1993-07-07 76.8 0 5 2021-07-07 76.4 0 Time Series Summary for Reading Area, PA (ThreadEx) Click column heading to sort ascending, click again to sort descending. 1 2024-07-07 76.7 0 2 1925-07-07 75.9 0 3 1966-07-07 75.8 0 4 1943-07-07 75.5 0 5 1949-07-07 75.3 0 - 1934-07-07 75.3 0 Time Series Summary for New Brunswick Area, NJ (ThreadEx) Click column heading to sort ascending, click again to sort descending. 1 2024-07-07 74.8 0 - 1899-07-07 74.8 0 2 2010-07-07 74.6 0 - 1901-07-07 74.6 0 3 1898-07-07 74.5 0 4 1925-07-07 74.4 0 5 1934-07-07 74.1 0 Time Series Summary for IGOR I SIKORSKY MEMORIAL AIRPORT, CT Click column heading to sort ascending, click again to sort descending. 1 2024-07-07 73.1 0 2 1994-07-07 73.0 0 3 2010-07-07 72.9 0 4 2008-07-07 72.6 0 5 1999-07-07 72.1 0 Time Series Summary for SOMERSET AIRPORT, NJ Click column heading to sort ascending, click again to sort descending. 1 2024-07-07 73.4 0 2 1999-07-07 72.6 7 3 2010-07-07 72.5 0 - 2005-07-07 72.5 0 4 2021-07-07 72.0 0 - 2013-07-07 72.0 0 - 2008-07-07 72.0 0 5 2020-07-07 71.9 0

BTV has us beat so far in that department. Data for June 1, 2024 through July 8, 2024 Click column heading to sort ascending, click again to sort descending. NJ NEWARK LIBERTY INTL AP WBAN 79 NY NY CITY CENTRAL PARK WBAN 79 NJ HARRISON COOP 78 NJ TETERBORO AIRPORT WBAN 78 NJ CALDWELL ESSEX COUNTY AP WBAN 78 NJ TETERBORO AIRPORT COOP 76 CT NEW HAVEN TWEED AP WBAN 76 NY LAGUARDIA AIRPORT WBAN 75 Data for June 1, 2024 through July 8, 2024 Click column heading to sort ascending, click again to sort descending. VT BURLINGTON INTERNATIONAL AIRPORT WBAN 80 NY CANTON 4 SE WBAN 75 NY MALONE COOP 75 VT VERGENNES COOP 75 VT ISLAND POND AP COOP 75

The record rainfall in places like the Northeast has probably been the most significant aspect of this record global temperature and moisture spike over the last year. Data for July 1, 2023 through July 8, 2024 Click column heading to sort ascending, click again to sort descending. CT PROSPECT 1.9 ENE CoCoRaHS 86.17 CT MIDDLEFIELD 1.4 W CoCoRaHS 84.54 CT NORWICH 2.5 NNE CoCoRaHS 83.78 CT OAKDALE 2.6 WNW CoCoRaHS 83.30 NY STONY POINT 0.7 NW CoCoRaHS 83.03 CT BROOKFIELD 3.3 SSE CoCoRaHS 82.84 CT MIDDLEFIELD 0.6 SE CoCoRaHS 82.82 CT WATERBURY 1.3 WNW CoCoRaHS 81.99 CT COLCHESTER 0.6 ENE CoCoRaHS 81.56 NY WEST POINT COOP 81.33 CT NORTHFORD 0.8 SW CoCoRaHS 81.21 CT HIGGANUM 0.7 N CoCoRaHS 81.18 CT GRISWOLD 0.9 N CoCoRaHS 81.14 NY CARMEL 4N COOP 81.02 CT HIGGANUM 0.8 NE CoCoRaHS 80.80 CT EAST LYME 0.5 SW CoCoRaHS 80.60 CT CHESTER CENTER 2.7 WNW CoCoRaHS 80.45 CT NAUGATUCK 1.7 NNE CoCoRaHS 80.44

This is one of the strongest La Niña background patterns that we have ever seen in July. The models are all forecasting the strongest Western Atlantic ridge on record this week to 603 dam. A La Niña in July usually features a ridge just off the East Coast. But the extreme marine heatwave over the WPAC and the Atlantic are combining for a new record.

All-time high temperatures in Japan with that record marine heatwave.

We usually don’t get to see such dense fog around the July 4 period with 75° dew points. New Haven FOG 76 75 97 CALM 29.94S VSB 1/4

The Euro still has numerous days here next week with PWATS in the 2.0 to 2.5 range. So moisture and heavy convection with beryls remnants could extend further east than what that model is printing out.

It bumped a little west with the heaviest axis of rainfall and its 600 dam + record WAR pattern. But it’s still way too early to determine where the actual axis of heaviest Beryl rain will be located. The heaviest axis will probably have torrential downpours with the Beryl remnants and also a PRE.

I posted recent papers on this topic in these discussion threads. There has been a rapid expansion of the WPAC warm pool since the early 80s. So forcing in those areas has been steadily increasing. More forcing there results in warmer winters for the Northeast. The period since 15-16 has been unprecedented for winter warmth in the recorded climate record. The next 5 winters will be important in determining what happens in the future. A 15 year period of observations can be helpful in determining if a new climate threshold has been crossed or not. The thing about climate thresholds is that you won’t know whether you crossed one until it’s pretty far back in the rear view mirror. We usually don’t know where they are ahead of time. So if these very warm winters are still occurring regularly by around 2030 then we may have already crossed the invisible threshold. I will continue to take one winter at a time and collect more data before making a determination one way or another. My guess is that the WPAC warming faster than the EPAC is increasing the trades along the equator in the Central Pacific leading to more frequent La Ninas.

I meant to say east of the Dateline. While that 500mb anomaly center south of the Aleutians has been steadily increasing, it has grown to unprecedented levels of strength and persistence since the 15-16 super El Niño. I zoomed into the 500mb anomaly center where you placed the arrow. I define the La Niña background state as record SSTs west of the Dateline along the equator in the MJO 4-6 regions and east of Japan to south of the Aleutians. So both the tropics to the mid-latitudes. We even had a ridge there last winter during the borderline super El Niño and during the uncoupled El Niños in 18-19 and 19-20. Anytime we have a strong enough ridge axis out south of the Aleutians it pumps up the Southeast ridge and or ridge over the Northeast. This is the main reason we have seen the first 9 year run of record to warmer than normal winters in a row for the Northeast.

But it’s not the subsurface east of the Dateline driving the pattern. This pattern also has a warmer surface component west of the Dateline. That warm pool at the surface over the WPAC is what has been producing the perma-La Niña background state since the 15-16 super El Niño.

Not much difference between +0.24 and +0.55 ONI as either in our older climate would have been more El Niño modoki-like.

One of the biggest examples of this was the warm neutral ONI to weak modoki El Niño in 19-20. It behaved more like a robust La Niña due to the record WPAC warm pool and marine heatwave east of Japan really amping up the Aleutian ridge and Southeast ridge. So the La Niña background state prevailed even with the SSTs approaching weak modoki status.

The exact track of the remnants will be important as to where the heaviest axis of rainfall sets up. But this pattern is much more amplified than normal. The 12z GFS is advertising the first 603 dam WAR pattern this week.

2nd day in a row with 80° dew points in NJ. https://www.njweather.org/maps/

The current Nino 3.4 is +0.4. But due to the record WPAC warmth driving the record -PDO we have been getting a very robust La Niña atmospheric response. The 100° heat in June and record breaking Beryl deepening so early is like an even more amped up La Niña response than usual with the record Atlantic SST boost. So my guess is that the happenings over the Western Pacific will continue to be more influential than what the official ONI readings are.

Dew points have been steadily rising as a warmer atmosphere holds more moisture. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=76&network=NY_ASOS&station=JFK&season=summer&varname=dwpf&agg=mean&year=1893&w=bar&hours=0-23&_r=t&dpi=100&_fmt=png

77° dew point here now after .82 of rain. My sunglasses actually fogged up going outside now that the sun is out. The area has a shot at one of the highest July average dew points for the whole month. https://www.weather.gov/wrh/timeseries?site=khvn https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=76&network=NJ_ASOS&station=SMQ&season=jul&varname=dwpf&agg=mean&year=1893&w=bar&hours=0-23&_r=t&dpi=100&_fmt=png