donsutherland1

Tomorrow will be partly sunny and pleasantly warm. Temperatures will again surge into the upper 80s and lower 90s on Tuesday and Wednesday before the next cold front crosses the region. In the long-range, August could wind up warmer to perhaps much warmer than normal based on the evolution of the MJO. The MJO was in Phase 1 with an amplitude between 1.500 and 2.000 on multiple days during the June 20-30 period. There were 8 prior cases similar to 2021. mean temperature for August was 77.1° following such cases. The 1991-20 mean temperature for was 76.0° for August. 88% of the August cases were warmer than the 1991-20 mean temperatures. Early prospects for a very warm second half of July have diminished on account of the MJO's having moved back into Phase 2 from Phase 3. The ENSO Region 1+2 anomaly was +0.1°C and the Region 3.4 anomaly was 0.0°C for the week centered around July 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged 0.10°C and the ENSO Region 3.4 anomaly has averaged -0.13°C. Neutral ENSO conditions will likely prevail through August. The SOI was +17.30 today. The preliminary Arctic Oscillation (AO) figure was +0.791 today. On July 16 the MJO was in Phase 4 at an amplitude of 0.995 (RMM). The July 15-adjusted amplitude was 0.970 (RMM). In late April, the MJO moved through Phase 8 at an extreme amplitude (+3.000 or above). Only February 25, 1988 and March 18-19, 2015 had a higher amplitude at Phase 8. Both 1988 and 2015 went on to have an exceptionally warm July-August period. July-August 1988 had a mean temperature of 79.1°, which ranked 4th highest for that two-month period. July-August 2015 had a mean temperature of 78.9°, which ranked 5th highest for that two-month period. September 2015 was also the warmest September on record. The MJO's extreme passage through Phase 8 could provide the first hint of a hot summer. Since 1896, 76% of years that saw Phoenix reach 115° or above in June, as occurred this year, had a warmer than July-August in the Middle Atlantic region. The ratio of top 30 July-August temperatures relative to bottom 30 temperatures was 6:1 in favor of the warmth. Overall, the ingredients continue to fall into place for a warmer than normal to potentially hot summer. Based on sensitivity analysis applied to the latest guidance, there is an implied 65% probability that New York City will have a cooler than normal July (1991-2020 normal). July will likely finish with a mean temperature near 76.8° (0.7° below normal).

What happened in the Pacific Northwest was unprecedented. There will be extreme heat in our region at some point. Things are warming and eventually it will happen. I would be surprised if it didn’t happen this decade.

All measures are important in providing a full picture of the climate. Outside of the increasingly dense “forest” in Central Park mean summer high temperatures are rising.

Morning thoughts… With rainfall through 8 am, July rainfall in New York City has reached 9.14”. That makes 2021 the 4th wettest July on record. At 8:30, a few small showers were working northeastward in northern New Jersey. Any rain will end this morning. The clouds could break during the afternoon. It will be cooler than yesterday. Temperatures will likely reach the lower and middle 80s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 83° Newark: 87° Philadelphia: 83° Normals: New York City: 30-Year: 85.3°; 15-Year: 86.4° Newark: 30-Year: 87.2°; 15-Year: 88.6° Philadelphia: 30-Year: 88.1°; 15-Year: 89.2° Tomorrow will be partly sunny and pleasant.

Parts of the region again saw temperatures surge into the 90s. However, a cold front that has already triggered thunderstorms will break the heat in much of the region. 90° Days for Select Cities (through July 17): Albany: 4 (2020: 13 days; 5-Year Average: 13.6 days) Allentown: 15 (2020: 24 days; 5-Year Average: 27.6 days) Baltimore: 26 (2020: 46 days; 5-Year Average: 44.6 days) Boston: 14 (2020: 14 days; 5-Year Average: 17.2 days) Bridgeport: 7 (2020: 11 days; 5-Year Average: 13.4 days) Burlington: 7 (2020: 20 days; 5-Year Average: 13.0 days) Harrisburg: 19 (2020: 35 days; 5-Year Average: 30.6 days) Hartford: 15 (2020: 39 days; 5-Year Average: 29.0 days) Islip: 3 (2020: 8 days; 5-Year Average: 9.4 days) New York City-JFK: 5 (2020: 12 days; 5-Year Average: 10.2 days) New York City-LGA: 15 (2020: 34 days; 5-Year Average: 29.4 days) New York City-NYC: 12 (2020: 20 days; 5-Year Average: 18.2 days) Newark: 24 (2020: 31 days; 5-Year Average: 31.2 days) Philadelphia: 20 (2020: 36 days; 5-Year Average: 34.6 days) Scranton: 12 (2020: 25 days; 5-Year Average: 16.4 days) Washington, DC: 22 (2020: 46 days; 5-Year Average: 50.8 days) New York City-Newark Average: 14 (2020: 22 days) ...Expected: 15 (based on regression equation tied to JFK-LGA-EWR data) Tomorrow will start out with clouds and possible showers and thundershowers. The clouds could break during the afternoon and humidity levels could fall. It will be cooler than today. In the long-range, August could wind up warmer to perhaps much warmer than normal based on the evolution of the MJO. The MJO was in Phase 1 with an amplitude between 1.500 and 2.000 on multiple days during the June 20-30 period. There were 8 prior cases similar to 2021. mean temperature for August was 77.1° following such cases. The 1991-20 mean temperature for was 76.0° for August. 88% of the August cases were warmer than the 1991-20 mean temperatures. Early prospects for a very warm second half of July have diminished on account of the MJO's having moved back into Phase 2 from Phase 3. Out West, some of the long-range guidance, including the latest EPS weeklies, suggest that a new expansive heat dome could develop over the western third of the United States and Canada toward the end of July or during the first week of August and then persist toward mid-month. The ENSO Region 1+2 anomaly was +0.1°C and the Region 3.4 anomaly was 0.0°C for the week centered around July 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged 0.10°C and the ENSO Region 3.4 anomaly has averaged -0.13°C. Neutral ENSO conditions will likely prevail through August. The SOI was +30.41 today. This was the third consecutive day on which the SOI was at +30.00 or above. The last time that happened was during December 17-19, 2020 when the SOI was at or above +30.00 for three consecutive days. The preliminary Arctic Oscillation (AO) figure was +1.363 today. On July 15 the MJO was in Phase 4 at an amplitude of 0.967 (RMM). The July 14-adjusted amplitude was 0.970 (RMM). In late April, the MJO moved through Phase 8 at an extreme amplitude (+3.000 or above). Only February 25, 1988 and March 18-19, 2015 had a higher amplitude at Phase 8. Both 1988 and 2015 went on to have an exceptionally warm July-August period. July-August 1988 had a mean temperature of 79.1°, which ranked 4th highest for that two-month period. July-August 2015 had a mean temperature of 78.9°, which ranked 5th highest for that two-month period. September 2015 was also the warmest September on record. The MJO's extreme passage through Phase 8 could provide the first hint of a hot summer. Since 1896, 76% of years that saw Phoenix reach 115° or above in June, as occurred this year, had a warmer than July-August in the Middle Atlantic region. The ratio of top 30 July-August temperatures relative to bottom 30 temperatures was 6:1 in favor of the warmth. Overall, the ingredients continue to fall into place for a warmer than normal to potentially hot summer. Based on sensitivity analysis applied to the latest guidance, there is an implied 65% probability that New York City will have a cooler than normal July (1991-2020 normal). July will likely finish with a mean temperature near 76.8° (0.7° below normal).

It’s not supposed to be listed as snow/sleet in the climate record. But the ASOS can’t distinguish between small hail and sleet.

Quality control needed. Note the snowfall section:

Thunderstorms grazed the New York Botanical Garden this afternoon knocking the temperature back into the 80s. Some light rain fell, but there were no downpours. The daylilies are now at or just past their peak bloom.

Yes, that's a black swallowtail.

Some photos from Robert Moses State Park yesterday. The sea breeze kept temperatures in the middle 80s.

Morning thoughts… It will be partly sunny and very warm today. An approaching cold front will trigger showers and thunderstorms, some of which could produce damaging winds and flooding downpours. Temperatures will likely reach the upper 80s and lower 90s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 89° Newark: 94° Philadelphia: 93° Normals: New York City: 30-Year: 85.3°; 15-Year: 86.4° Newark: 30-Year: 87.3°; 15-Year: 88.6° Philadelphia: 30-Year: 88.1°; 15-Year: 89.2° Rain should end during tomorrow morning and clouds could break. It will be cooler.

Under mostly sunny skies, temperatures surged into the lower and middle 90s across the region. 90° Days for Select Cities (through July 16): Albany: 4 (2020: 13 days; 5-Year Average: 13.6 days) Allentown: 14 (2020: 24 days; 5-Year Average: 27.6 days) Baltimore: 25 (2020: 46 days; 5-Year Average: 44.6 days) Boston: 14 (2020: 14 days; 5-Year Average: 17.2 days) Bridgeport: 7 (2020: 11 days; 5-Year Average: 13.4 days) Burlington: 7 (2020: 20 days; 5-Year Average: 13.0 days) Harrisburg: 18 (2020: 35 days; 5-Year Average: 30.6 days) Hartford: 14 (2020: 39 days; 5-Year Average: 29.0 days) Islip: 3 (2020: 8 days; 5-Year Average: 9.4 days) New York City-JFK: 5 (2020: 12 days; 5-Year Average: 10.2 days) New York City-LGA: 14 (2020: 34 days; 5-Year Average: 29.4 days) New York City-NYC: 11 (2020: 20 days; 5-Year Average: 18.2 days) Newark: 23 (2020: 31 days; 5-Year Average: 31.2 days) Philadelphia: 19 (2020: 36 days; 5-Year Average: 34.6 days) Scranton: 11 (2020: 25 days; 5-Year Average: 16.4 days) Washington, DC: 21 (2020: 46 days; 5-Year Average: 50.8 days) New York City-Newark Average: 13 (2020: 22 days) ...Expected: 14 (based on regression equation tied to JFK-LGA-EWR data) The weekend could see more clouds and perhaps thundershowers. In the long-range, August could wind up warmer to perhaps much warmer than normal based on the evolution of the MJO. The MJO was in Phase 1 with an amplitude between 1.500 and 2.000 on multiple days during the June 20-30 period. There were 8 prior cases similar to 2021. mean temperature for August was 77.1° following such cases. The 1991-20 mean temperature for was 76.0° for August. 88% of the August cases were warmer than the 1991-20 mean temperatures. Early prospects for a very warm second half of July have diminished on account of the MJO's having moved back into Phase 2 from Phase 3. Out West, some of the long-range guidance, including the latest EPS weeklies, suggest that a new expansive heat dome could develop over the western third of the United States and Canada toward the end of July or during the first week of August and then persist toward mid-month. The ENSO Region 1+2 anomaly was +0.1°C and the Region 3.4 anomaly was 0.0°C for the week centered around July 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged 0.10°C and the ENSO Region 3.4 anomaly has averaged -0.13°C. Neutral ENSO conditions will likely prevail through August. The SOI was +33.05 today. This was the second consecutive day on which the SOI was at +30.00 or above. The last time that happened was during December 17-19, 2020 when the SOI was at or above +30.00 for three consecutive days. The preliminary Arctic Oscillation (AO) figure was +1.363 today. On July 14 the MJO was in Phase 2 at an amplitude of 0.970 (RMM). The July 13-adjusted amplitude was 0.939 (RMM). In late April, the MJO moved through Phase 8 at an extreme amplitude (+3.000 or above). Only February 25, 1988 and March 18-19, 2015 had a higher amplitude at Phase 8. Both 1988 and 2015 went on to have an exceptionally warm July-August period. July-August 1988 had a mean temperature of 79.1°, which ranked 4th highest for that two-month period. July-August 2015 had a mean temperature of 78.9°, which ranked 5th highest for that two-month period. September 2015 was also the warmest September on record. The MJO's extreme passage through Phase 8 could provide the first hint of a hot summer. Since 1896, 76% of years that saw Phoenix reach 115° or above in June, as occurred this year, had a warmer than July-August in the Middle Atlantic region. The ratio of top 30 July-August temperatures relative to bottom 30 temperatures was 6:1 in favor of the warmth. Overall, the ingredients continue to fall into place for a warmer than normal to potentially hot summer. Based on sensitivity analysis applied to the latest guidance, there is an implied 60% probability that New York City will have a cooler than normal July (1991-2020 normal). July will likely finish with a mean temperature near 76.9° (0.6° below normal).

Morning thoughts… A hot and humid day lies ahead. It will be partly sunny and hot. A few locations could see an afternoon or evening thundershower. Temperatures will likely reach the lower and middle 90s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 92° Newark: 97° Philadelphia: 93° Normals: New York City: 30-Year: 85.2°; 15-Year: 86.3° Newark: 30-Year: 87.3°; 15-Year: 88.5° Philadelphia: 30-Year: 88.1°; 15-Year: 89.2° Tomorrow will be variably cloudy and very warm with an increasing chance of showers and thunderstorms.

Some climate data for Billings:

The thermometer soared into the upper 80s and lower 90s across the region today. 90° Days for Select Cities (through July 15): Albany: 4 (2020: 13 days; 5-Year Average: 13.6 days) Allentown: 13 (2020: 24 days; 5-Year Average: 27.6 days) Baltimore: 24 (2020: 46 days; 5-Year Average: 44.6 days) Boston: 13 (2020: 14 days; 5-Year Average: 17.2 days) Bridgeport: 6 (2020: 11 days; 5-Year Average: 13.4 days) Burlington: 7 (2020: 20 days; 5-Year Average: 13.0 days) Harrisburg: 17 (2020: 35 days; 5-Year Average: 30.6 days) Hartford: 13 (2020: 39 days; 5-Year Average: 29.0 days) Islip: 3 (2020: 8 days; 5-Year Average: 9.4 days) New York City-JFK: 5 (2020: 12 days; 5-Year Average: 10.2 days) New York City-LGA: 13 (2020: 34 days; 5-Year Average: 29.4 days) New York City-NYC: 10 (2020: 20 days; 5-Year Average: 18.2 days) Newark: 22 (2020: 31 days; 5-Year Average: 31.2 days) Philadelphia: 18 (2020: 36 days; 5-Year Average: 34.6 days) Scranton: 11 (2020: 25 days; 5-Year Average: 16.4 days) Washington, DC: 20 (2020: 46 days; 5-Year Average: 50.8 days) New York City-Newark Average: 13 (2020: 22 days) ...Expected: 13 (based on regression equation tied to JFK-LGA-EWR data) Tomorrow will be another very warm and humid day with highs in the upper 80s and lower 90s. The weekend could see more clouds and perhaps thundershowers. In the long-range, August could wind up warmer to perhaps much warmer than normal based on the evolution of the MJO. The MJO was in Phase 1 with an amplitude between 1.500 and 2.000 on multiple days during the June 20-30 period. There were 8 prior cases similar to 2021. mean temperature for August was 77.1° following such cases. The 1991-20 mean temperature for was 76.0° for August. 88% of the August cases were warmer than the 1991-20 mean temperatures. Early prospects for a very warm second half of July have diminished on account of the MJO's having moved back into Phase 2 from Phase 3. The ENSO Region 1+2 anomaly was +0.1°C and the Region 3.4 anomaly was 0.0°C for the week centered around July 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged 0.10°C and the ENSO Region 3.4 anomaly has averaged -0.13°C. Neutral ENSO conditions will likely prevail through August. The SOI was +37.86 today. That is the highest SOI value since January 15, 2014 when the SOI was +50.17. The preliminary Arctic Oscillation (AO) figure was +1.750 today. On July 13 the MJO was in Phase 2 at an amplitude of 0.941 (RMM). The July 12-adjusted amplitude was 1.091 (RMM). In late April, the MJO moved through Phase 8 at an extreme amplitude (+3.000 or above). Only February 25, 1988 and March 18-19, 2015 had a higher amplitude at Phase 8. Both 1988 and 2015 went on to have an exceptionally warm July-August period. July-August 1988 had a mean temperature of 79.1°, which ranked 4th highest for that two-month period. July-August 2015 had a mean temperature of 78.9°, which ranked 5th highest for that two-month period. September 2015 was also the warmest September on record. The MJO's extreme passage through Phase 8 could provide the first hint of a hot summer. Since 1896, 76% of years that saw Phoenix reach 115° or above in June, as occurred this year, had a warmer than July-August in the Middle Atlantic region. The ratio of top 30 July-August temperatures relative to bottom 30 temperatures was 6:1 in favor of the warmth. Overall, the ingredients continue to fall into place for a warmer than normal to potentially hot summer. Based on sensitivity analysis applied to the latest guidance, there is an implied 63% probability that New York City will have a cooler than normal July (1991-2020 normal). July will likely finish with a mean temperature near 76.9° (0.6° below normal).

Morning thoughts… A very warm and humid day lies ahead. It will be partly cloudy and very warm today. Temperatures will likely reach the upper 80s and lower 90s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 89° Newark: 93° Philadelphia: 93° Normals: New York City: 30-Year: 85.2°; 15-Year: 86.3° Newark: 30-Year: 87.3°; 15-Year: 88.5° Philadelphia: 30-Year: 88.1°; 15-Year: 89.2° Tomorrow will be partly sunny and hot.

Washington, DC to Newark saw temperatures rise into the 90s. Tomorrow will be another steamy day with highs in the upper 80s and lower 90s. Through Friday, temperatures will continue to top out mainly in the upper 80s and lower 90s. The weekend could see more clouds and perhaps thundershowers. In the long-range, August could wind up warmer to perhaps much warmer than normal based on the evolution of the MJO. The MJO was in Phase 1 with an amplitude between 1.500 and 2.000 on multiple days during the June 20-30 period. There were 8 prior cases similar to 2021. mean temperature for August was 77.1° following such cases. The 1991-20 mean temperature for was 76.0° for August. 88% of the August cases were warmer than the 1991-20 mean temperatures. Early prospects for a very warm second half of July have diminished on account of the MJO's having moved back into Phase 2 from Phase 3. The ENSO Region 1+2 anomaly was +0.1°C and the Region 3.4 anomaly was 0.0°C for the week centered around July 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged 0.10°C and the ENSO Region 3.4 anomaly has averaged -0.13°C. Neutral ENSO conditions will likely prevail through August. The SOI was +26.22 today. The preliminary Arctic Oscillation (AO) figure was +1.496 today. On July 12 the MJO was in Phase 2 at an amplitude of 1.091 (RMM). The July 11-adjusted amplitude was 1.391 (RMM). In late April, the MJO moved through Phase 8 at an extreme amplitude (+3.000 or above). Only February 25, 1988 and March 18-19, 2015 had a higher amplitude at Phase 8. Both 1988 and 2015 went on to have an exceptionally warm July-August period. July-August 1988 had a mean temperature of 79.1°, which ranked 4th highest for that two-month period. July-August 2015 had a mean temperature of 78.9°, which ranked 5th highest for that two-month period. September 2015 was also the warmest September on record. The MJO's extreme passage through Phase 8 could provide the first hint of a hot summer. Since 1896, 76% of years that saw Phoenix reach 115° or above in June, as occurred this year, had a warmer than July-August in the Middle Atlantic region. The ratio of top 30 July-August temperatures relative to bottom 30 temperatures was 6:1 in favor of the warmth. Overall, the ingredients continue to fall into place for a warmer than normal to potentially hot summer. Based on sensitivity analysis applied to the latest guidance, there is an implied 58% probability that New York City will have a cooler than normal July (1991-2020 normal). July will likely finish with a mean temperature near 77.1° (0.4° below normal).

Morning thoughts… A steamy day is in order. It will be partly cloudy and very warm today. There could be some scattered showers or thundershowers in parts of the region. Temperatures will likely reach the upper 80s and lower 90s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 88° Newark: 93° Philadelphia: 90° Normals: New York City: 30-Year: 85.2°; 15-Year: 86.2° Newark: 30-Year: 87.3°; 15-Year: 88.5° Philadelphia: 30-Year: 88.1°; 15-Year: 89.1° Tomorrow will be partly sunny and hot.

Warmer air was confined to Philadelphia and southward. While Baltimore hit 96°, New York City's Central Park rose only to 72°. The warm front will gradually move northward tonight and tomorrow. As a result, tomorrow will be variably cloudy and noticeably warmer. Showers or thundershowers are possible. The remainder of the work week will see temperatures mainly in the upper 80s and lower 90s. The second half of July and August could wind up warmer to perhaps much warmer than normal based on the evolution of the MJO. The MJO was in Phase 1 with an amplitude between 1.500 and 2.000 on multiple days during the June 20-30 period. There were 8 prior cases similar to 2021. The mean temperature for New York City during the July 16-31 period was 79.4° and the mean temperature for August was 77.1° following such cases. The 1991-20 mean temperature for July 16-31 was 77.9° and 76.0° for August. 75% of the July 16-31 cases and 88% of the August cases were warmer than the 1991-20 mean temperatures. The ENSO Region 1+2 anomaly was +0.1°C and the Region 3.4 anomaly was 0.0°C for the week centered around July 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged 0.10°C and the ENSO Region 3.4 anomaly has averaged -0.13°C. Neutral ENSO conditions will likely prevail through August. The SOI was +17.24 today. The preliminary Arctic Oscillation (AO) figure was +1.369 today. On July 11 the MJO was in Phase 2 at an amplitude of 1.391 (RMM). The July 10-adjusted amplitude was 1.382 (RMM). In late April, the MJO moved through Phase 8 at an extreme amplitude (+3.000 or above). Only February 25, 1988 and March 18-19, 2015 had a higher amplitude at Phase 8. Both 1988 and 2015 went on to have an exceptionally warm July-August period. July-August 1988 had a mean temperature of 79.1°, which ranked 4th highest for that two-month period. July-August 2015 had a mean temperature of 78.9°, which ranked 5th highest for that two-month period. September 2015 was also the warmest September on record. The MJO's extreme passage through Phase 8 could provide the first hint of a hot summer. Since 1896, 76% of years that saw Phoenix reach 115° or above in June, as occurred this year, had a warmer than July-August in the Middle Atlantic region. The ratio of top 30 July-August temperatures relative to bottom 30 temperatures was 6:1 in favor of the warmth. Overall, the ingredients continue to fall into place for a warmer than normal to potentially hot summer. Based on sensitivity analysis applied to the latest guidance, there is an implied 44% probability that New York City will have a warmer than normal July (1991-2020 normal). July will likely finish with a mean temperature near 77.2° (0.3° below normal).

It’s more than likely that any NWS outreach occurred prior to Mr. Ceglarek’s tenure, possibly the late 1990s or early 2000s.

Morning thoughts… It will be mostly cloudy and somewhat cooler today. There could still be a scattered shower or thundershower. Temperatures will likely reach the upper 70s and lower 80s in most of the region. Philadelphia to Washington, DC will see readings in the 90s. Likely high temperatures around the region include: New York City (Central Park): 78° Newark: 82° Philadelphia: 91° Normals: New York City: 30-Year: 85.1°; 15-Year: 86.1° Newark: 30-Year: 87.3°; 15-Year: 88.4° Philadelphia: 30-Year: 88.1°; 15-Year: 89.1° Tomorrow will be partly sunny and warmer.

Some extreme rainfall amounts:

Under partly sunny skies, temperatures surged into the 80s in the northern Mid-Atlantic region. South of there, especially from Newark, temperatures rose into the 90s. 90° Days for Select Cities (through July 12): Albany: 4 (2020: 13 days; 5-Year Average: 13.6 days) Allentown: 13 (2020: 24 days; 5-Year Average: 27.6 days) Baltimore: 21 (2020: 46 days; 5-Year Average: 44.6 days) Boston: 13 (2020: 14 days; 5-Year Average: 17.2 days) Bridgeport: 6 (2020: 11 days; 5-Year Average: 13.4 days) Burlington: 7 (2020: 20 days; 5-Year Average: 13.0 days) Harrisburg: 15 (2020: 35 days; 5-Year Average: 30.6 days) Hartford: 13 (2020: 39 days; 5-Year Average: 29.0 days) Islip: 3 (2020: 8 days; 5-Year Average: 9.4 days) New York City-JFK: 5 (2020: 12 days; 5-Year Average: 10.2 days) New York City-LGA: 11 (2020: 34 days; 5-Year Average: 29.4 days) New York City-NYC: 10 (2020: 20 days; 5-Year Average: 18.2 days) Newark: 20 (2020: 31 days; 5-Year Average: 31.2 days) Philadelphia: 16 (2020: 36 days; 5-Year Average: 34.6 days) Scranton: 11 (2020: 25 days; 5-Year Average: 16.4 days) Washington, DC: 17 (2020: 46 days; 5-Year Average: 50.8 days) New York City-Newark Average: 12 (2020: 22 days) ...Expected: 12 (based on regression equation tied to JFK-LGA-EWR data) Tomorrow will be variably cloudy and cooler in the northern Mid-Atlantic region. Showers and thundershowers are possible. Washington, DC to Philadelphia will likely see readings surge into the lower and middle 90s. In the long-range, the second half of July and August could wind up warmer to perhaps much warmer than normal based on the evolution of the MJO. The MJO was in Phase 1 with an amplitude between 1.500 and 2.000 on multiple days during the June 20-30 period. There were 8 prior cases similar to 2021. The mean temperature for New York City during the July 16-31 period was 79.4° and the mean temperature for August was 77.1° following such cases. The 1991-20 mean temperature for July 16-31 was 77.9° and 76.0° for August. 75% of the July 16-31 cases and 88% of the August cases were warmer than the 1991-20 mean temperatures. The ENSO Region 1+2 anomaly was +0.1°C and the Region 3.4 anomaly was 0.0°C for the week centered around July 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged 0.10°C and the ENSO Region 3.4 anomaly has averaged -0.13°C. Neutral ENSO conditions will likely prevail through August. The SOI was +17.24 today. The preliminary Arctic Oscillation (AO) figure was +1.253 today. On July 10 the MJO was in Phase 2 at an amplitude of 1.381 (RMM). The July 9-adjusted amplitude was 1.329 (RMM). In late April, the MJO moved through Phase 8 at an extreme amplitude (+3.000 or above). Only February 25, 1988 and March 18-19, 2015 had a higher amplitude at Phase 8. Both 1988 and 2015 went on to have an exceptionally warm July-August period. July-August 1988 had a mean temperature of 79.1°, which ranked 4th highest for that two-month period. July-August 2015 had a mean temperature of 78.9°, which ranked 5th highest for that two-month period. September 2015 was also the warmest September on record. The MJO's extreme passage through Phase 8 could provide the first hint of a hot summer. Since 1896, 76% of years that saw Phoenix reach 115° or above in June, as occurred this year, had a warmer than July-August in the Middle Atlantic region. The ratio of top 30 July-August temperatures relative to bottom 30 temperatures was 6:1 in favor of the warmth. Overall, the ingredients continue to fall into place for a warmer than normal to potentially hot summer. Based on sensitivity analysis applied to the latest guidance, there is an implied 46% probability that New York City will have a warmer than normal July (1991-2020 normal). July will likely finish with a mean temperature near 77.3° (0.2° below normal).

A recent paper: https://sciencebrief.org/uploads/reviews/ScienceBrief_Review_RAINFALL_Jun2021.pdf

It is.