bluewave

Newark came closest in July 1966 reaching 100°. So the number to watch will be 101°+. All the other years stayed under 100° in the following 15 days of 104°+. July 1949 made it back to 101° on the 28th which was 24 days after. 1966-07-03 105 75 90.0 12.6 0 25 0.00 0.0 0 1966-07-04 100 78 89.0 11.5 0 24 0.00 0.0 0 1966-07-05 87 74 80.5 2.8 0 16 0.00 0.0 0 1966-07-06 87 73 80.0 2.2 0 15 T 0.0 0 1966-07-07 93 76 84.5 6.6 0 20 T 0.0 0 1966-07-08 91 70 80.5 2.4 0 16 0.00 0.0 0 1966-07-09 89 67 78.0 -0.2 0 13 0.00 0.0 0 1966-07-10 93 70 81.5 3.3 0 17 0.00 0.0 0 1966-07-11 96 72 84.0 5.7 0 19 0.00 0.0 0 1966-07-12 98 72 85.0 6.6 0 20 0.00 0.0 0 1966-07-13 100 77 88.5 10.1 0 24 0.00 0.0 1949-07-04 105 74 89.5 12.0 0 25 0.08 0.0 0 1949-07-05 95 73 84.0 6.3 0 19 0.00 0.0 0 1949-07-06 83 68 75.5 -2.3 0 11 0.47 0.0 0 1949-07-07 81 64 72.5 -5.4 0 8 0.06 0.0 0 1949-07-08 81 65 73.0 -5.1 0 8 0.00 0.0 0 1949-07-09 81 61 71.0 -7.2 0 6 0.00 0.0 0 1949-07-10 76 64 70.0 -8.2 0 5 0.13 0.0 0 1949-07-11 86 67 76.5 -1.8 0 12 0.00 0.0 0 1949-07-12 81 69 75.0 -3.4 0 10 0.17 0.0 0 1949-07-13 85 69 77.0 -1.4 0 12 0.56 0.0 0 1949-07-14 91 67 79.0 0.5 0 14 0.00 0.0 0 1949-07-15 80 71 75.5 -3.0 0 11 0.22 0.0 0 1949-07-16 81 71 76.0 -2.5 0 11 0.00 0.0 0 1949-07-17 75 70 72.5 -6.0 0 8 1.17 0.0 0 1949-07-18 93 70 81.5 3.0 0 17 T 0.0 0 1949-07-19 94 72 83.0 4.5 0 18 T 0.0 0 1949-07-20 94 74 84.0 5.5 0 19 0.00 0.0 0 1949-07-21 94 77 85.5 7.0 0 21 T 0.0 0 1949-07-22 97 75 86.0 7.5 0 21 0.01 0.0 0 1949-07-23 90 71 80.5 2.1 0 16 0.00 0.0 0 1949-07-24 90 63 76.5 -1.9 0 12 0.00 0.0 0 1949-07-25 94 69 81.5 3.2 0 17 0.03 0.0 0 1949-07-26 88 71 79.5 1.2 0 15 0.00 0.0 0 1949-07-27 97 71 84.0 5.8 0 19 T 0.0 0 1949-07-28 101 75 88.0 9.8 0 23 T 0.0 0 1949-07-29 100 75 87.5 9.4 0 23 0.00 0.0 0 1949-07-30 101 75 88.0 9.9 0 23 0.05 0.0

This will be the first 101°+ potential less than 15 days after 104°+ during July and August.

Really extreme over the top heatwave with parts of the Rockies and Plains approaching all-time highs today. The record 600 DM ridge will become very compressed leading to the 850 mb heat plume tracking through the Upper Great Lakes and Ontario next few days. The heat should peak in our area on Wednesday. Both the Euro and GFS have 100°-103° highs at the warm spots around the region. 101°+ would be a first to follow so quickly after 104°-106° heat earlier in the month.

This July is the most extreme difference between a developing super El Niño and the midlatitude 500 mb and temperature pattern across the CONUS. The tropics are clearly in El Niño mode as we can see from the forcing and -SOI with very strong shear over the Caribbean. Notice how the strong -PDO ridge north of Hawaii leads to the classic July -PDO SST pattern. This is an impressive July -PDO response across the CONUS with the record heat and ridging from the Plains to the East Coast. Strong July -PDO composites July 1-10, 2026 500 mb pattern

No doubt a cold month for that region. Just not as cold as the DMI ECMWF data. The persistence of low pressure closer to the Pacific side of the Arctic is a function of the big summer dipole reversal since 2013. This weaker dipole is the main reason that the 2012 record low has held into the 2020s.

This is the actual ERA 5 temperature map which produced the climate record for June 2026. The Pacific Arctic area to the north of Alaska did have its coldest June since the 1940s as I mentioned in my first post. But you can see how the total area from 80N to 90N had zones closest to the warmest on record on the Atlantic side. So the actual rank of the high Arctic wasn’t the coldest on record. Since the totality of the Arctic north of 60N had the warmest June on record. Even the less reliable ECWMF only starts in 2002, so an apples to apples comparison to any year earlier than 2002 can’t be made. This is why we use Era 5 for comparison to times since the 1940s.

The shifted nature of the ridges further south than usual over the CONUS is probably related to the persistent marine heatwave and 500 mb pattern from Japan to north of Hawaii driving the -PDO and contributing to the +AMO. A recent study found that this process is operating independently from the El Nino. So this more La Nina background pattern is overlapping with the developing super El Nino. If this interaction continues into the winter, then the El Nino ridge axis normally south of Hudson Bay could be located further south than usual. We’ll just have to see how the pattern evolves moving into the winter. https://www.science.org/doi/10.1126/sciadv.adz4647 Marine heatwaves in the Northwestern Pacific (NWP) have become increasingly frequent and persistent, yet the mechanisms enabling their multiseasonal duration remain poorly understood. Through observational analyses and climate model experiments, we demonstrate that NWP marine heatwaves are primarily driven by a quasistationary wavenumber 5 circumglobal wave (CGW) pattern that operates independently of El Niño–Southern Oscillation. The CGW modulates surface heat fluxes during summer, triggering a self-reinforcing feedback loop where NWP warming intensifies the CGW pattern, amplifying and prolonging heatwaves across extended warm seasons. Additionally, CGW-driven summer warming in the northern North Atlantic persists into winter through oceanic thermal inertia, exciting a great-circle wave pattern that propagates back to the NWP, sustaining heatwaves through cold seasons. This interplay between atmospheric waves and trans-basin interactions enables multiyear marine heatwave events. Analysis of observational data and climate model simulations reveals a strengthening CGW influence in recent decades, indicating more frequent and prolonged NWP marine heatwaves under ongoing global warming.

The forecast record breaking 600 DM ridge next week in the Upper Midwest is yet another pattern since May that doesn’t fit the typical developing record super El Niño playbook.

RECORD EVENT REPORT NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 0154 AM EDT FRI JUL 10 2026 ...RECORD DAILY MAXIMUM RAINFALL SET AT PHILADELPHIA PA... A RECORD RAINFALL OF 2.70 INCHES WAS SET AT PHILADELPHIA PA TODAY. THIS BREAKS THE OLD DAILY RECORD OF 1.79 INCHES SET IN 1952. THIS IS ALSO THE FIRST DAILY PRECIPITATION VALUE GREATER THAN 2 INCHES FOR PHILADELPHIA IN 837 DAYS, WHICH ENDS THE 4TH LONGEST SUCH STREAK ON RECORD. PRECIPITATION RECORDS FOR THE PHILADELPHIA PA AREA DATE BACK TO NOVEMBER 1871.

https://ocean.dmi.dk/arctic/meant80n_anomaly.uk.php As described in the data information sheet, the +80N mean temperature index is not a climate data record. Since 2002, the daily mean temperatures are calculated from the operational atmosphere model at ECMWF, and changes in the operational model over time may affect the resulting temperature trends. The effect of this should be considered before making firm conclusions on basis of trends in the +80N climate indices.

This will be a very rare pancake heat dome Notice how compressed the forecast record 600 dm heights for the MSP area will be. So the 850 mb plume will be fairly narrow. If it ejects perfectly coinciding with the daily highs next week around 4pm then my guess is the warm spots could reach 100° to 103°. If the warmest 850 mb temperatures occur at night then the daytime max could only be 96° to 100° for the warm spots. This is probably why each model is flipping from run to run since the timing of the peak 850 mb temperatures keeps changing. Fairly narrow 850 mb plume

Even though the areas north of 60N had their warmest June on record, a small area of the Arctic to the north of Alaska had their coldest June on record. This Beaufort Sea region is a key area in determining what the annual sea ice minimum in September will be. Early season weak dipole patterns which are colder in this region have been common since 2013. It indicates locally fewer melt ponds and a better pattern for sea ice retention toward the Pacific side of the Arctic. Seasons like 2012 and 2020 had very strong dipole patterns which preconditioned the ice for a big melt out by August and September. Most seasons since 2013 have finished in the 4.0 to 4.9 million sq km range for extent. Only 2012 and 2020 finished below 4.0 million sq km due to extreme dipole patterns and early record melt ponding. Climatologist49 ‪@climatologist49.bsky.social‬ Follow For the combined area poleward of 60N, this was the warmest June on record - despite the fact that a portion of the area north of Alaska had its coldest June on record (since 1940). @alaskawx.bsky.social 10:51 PM · Jul 6, 2026 Arctic Temperatures https://alaskaclimate.substack.com/p/june-2026-arctic-and-alaska-climate June was very mild over a large part of the Arctic. About 70 percent of the Arctic (land and seas poleward of 60°N) had a warmer than average June relative to the 1991-2020 baseline (Fig. 1). But almost 85 percent of Arctic land areas were milder than normal. About 12 percent of the Arctic had the warmest June since 1950 in ERA5 reanalysis, while only 1 percent had the coldest June in the past 77 years. The warmth was most dramatic in western Siberia. For Yamalo-Nenets Autonomous Okrug this was by far the warmest June on record. For the third time in the past five years, Svalbard had the warmest June on record. Parts of the Northwest Territories and southern Nunavut, Canada also had the warmest June on record. Areas with below normal temperatures were more restricted. June was quite chilly north of about 75N over the Canadian Arctic Islands and westward into the Arctic basin east of the dateline as well as on Alaska’s North Slope. Of special note was the extreme warmth in northwest Siberia on June 25. Beliy Island (73.3°N), just offshore of the Yamal Peninsula, reached 28.3C (83F). According to M. Herrera on his “Extreme Temperatures Around the World” Bluesky account, this is (apparently) the highest temperature on record so far north anywhere in the world. This heat was concurrent with the late June western and central European heatwave but was entirely distinct, as Russia east of Ural Mountains was generally cooler than normal during this time. Since 1950, this was easily the warmest June on record for the Arctic overall (Fig. 2) and the mildest since 2020. Arctic lands also had the highest June average temperature.

First time that Harrison,NJ away from the sea breeze reached 20 days of 90° or greater by July 8th. The station is in 3rd place for 95° days at 8. They are in 1st place with 4 days reaching 100°. The New Brunswick COOP is 2nd only to 2010 for the warmest average summer high temperature through June 8th. This matches the entire region which has numerous top 5 for average maximum temperature so far. Time Series Summary for HARRISON, NJ Most 90° days by July 8th Click column heading to sort ascending, click again to sort descending. 1 2026-07-08 20 0 - 2010-07-08 20 17 2 2018-07-08 18 0 3 2024-07-08 17 0 - 2021-07-08 17 0 - 2002-07-08 17 5 Time Series Summary for HARRISON, NJ Most 95° days by July 8th Click column heading to sort ascending, click again to sort descending. 1 2012-07-08 11 19 2 2021-07-08 9 0 3 2026-07-08 8 0 - 2010-07-08 8 17 Time Series Summary for HARRISON, NJ Click column heading to sort ascending, click again to sort descending. 1 2026-07-08 4 0 2 2025-07-08 3 0 - 2010-07-08 3 17 3 2021-07-08 2 0 - 2012-07-08 2 19 - 1999-07-08 2 1 Time Series Summary for NEW BRUNSWICK 3 SE, NJ Highest average maximum temperature June 1 to July 8 Click column heading to sort ascending, click again to sort descending. 1 2010-07-08 87.2 0 2 2026-07-08 86.3 0 3 2024-07-08 86.1 0 4 1999-07-08 84.8 0 5 2008-07-08 84.7 0

Yeah, this is going to be a very impressive ridge for that part of North America. MPX has a shot at a new all-time 500 mb height record. The previous record is less than three years old.