donsutherland1

No one has made the misleading argument that 'statistics cause or drive weather.' They are measures. Nothing more. Statistics measure the state of weather and, over longer timeframes, the state of the climate. Climate change in the conventional use of the term concerns the changes taking place among, other things, measures of temperature, precipitation, etc. The data is now almost unequivocal that the world has been warming. The scientific research also overwhelmingly attributes that warming to anthropogenic factors. The literature reveals that the increased tendency for hot and dry conditions is creating more favorable conditions for wildfires. The massive wildfires witnessed in recent years in Australia, California, parts of Europe, and Siberia are not random occurrences. The climate research has already accurately forecast an increased incidence of such events.

The date unequivocally show that climate change is boosting such warm minimum temperatures. With regard to Islip, the 30-year moving averages for the periods ending in 2000 and later are: 2000: 18.9 days/year 2010: 20.4 days/year 2020: 23.7 days/year (using data through 8/14) Islip has seen that figure increase by nearly 2.5 days per decade since 2000. The coefficient of determination is > 0.95. Whether one is dealing with urban areas having mature footprints, suburban or exurban areas, one finds the same trend in increasing minimum temperatures (and temperatures overall).

Morning thoughts... At 9:12 am, a dying thunderstorm was located near Waterbury and headed east-southeastward. Following the departure of that thunderstorm, clouds should break in Hartford allowing the temperature to approach or reach 90°. If the temperature reaches 90°, that would be Hartford's record-breaking 39th such day this summer. The record is 38 days, which was set in 1983 and tied in 2020. Around the region, 9 am temperatures included: Hartford: 75° New York City: 78° Newark: 80° Philadelphia: 77° Poughkeepsie: 77° Much of the region will see high temperatures in the upper 80s and lower 90s. Parts of the area could see a strong or severe thunderstorm this afternoon or evening. Laura is now a hurricane with maximum sustained winds of 75 mph. There is a distinct possibility that it could be this season's first major landfalling hurricane. The remnants of Laura could exit off the Delmarva Peninsula this weekend.

Unfortunately, the added heat from the growing greenhouse gas forcing is triggering more extremes. Balance is being sought in more damaging fashion.

Another relevant article on the California fires and climate change: https://yaleclimateconnections.org/2020/08/climate-change-is-worsening-californias-hellish-wildfires/

Under partly to mostly sunny skies, readings soared into the upper 80s and even some lower 90s across the region today. Parts of the region, especially eastern Pennsylvania and also New England saw scattered thunderstorms. Highs included: Allentown: 89° Baltimore: 91° Harrisburg: 92° Hartford: 89° Islip: 88° New York City-JFK: 88° New York City-LGA: 93° (tied record set in 1998) New York City-NYC: 90° Newark: 93° Philadelphia: 91° Washington, DC: 89° 90° Days for Select Cities (through August 24): Albany: 13 (2019: 12 days) Allentown: 23 (2019: 24 days) Baltimore: 42 (2019: 59 days) Boston: 14 (2019: 15 days) Burlington: 20 (2019: 8 days) Harrisburg: 32 (2019: 33 days) Hartford: 38 (2019: 27 days) Islip: 6 (2019: 8 days) New York City-JFK: 10 (2019: 7 days) New York City-LGA: 32 (2019: 26 days) New York City-NYC: 19 (2019: 15 days) Newark: 29 (2019: 28 days) Philadelphia: 33 (2019: 35 days) Scranton: 24 (2019: 12 days) Washington, DC: 41 (2019: 62 days) New York City-Newark Average: 23 (2019: 19 days) ...Expected: 23 (based on regression equation tied to JFK-LGA-EWR data) Tomorrow could again see readings approach or reach 90° in much of the region. There will be a risk of strong to possibly severe thunderstorms. The month could end on a cool note before temperatures return to above normal levels during the first week of September. The remnants of Laura could exit off the Delmarva Peninsula this weekend. The system has the potential to bring a period of heavy rain along or near its path and another area of heavy rain along a frontal boundary to its north. There remains some uncertainty about Laura's track and the location of the front. The current predominantly warmer than normal pattern will likely persist through much of September, providing a warm start to fall throughout the region. Occasional short-lived cool shots remain possible. Parts of the West continued to experience near record to record warmth. Select high temperatures included: Death Valley, CA: 120° Denver: 98° (tied record set in 2011) Flagstaff: 87° Kingman, AZ: 106° Lake Havasu City, AZ: 113° Las Vegas: 107° Needles, CA: 116° Palm Springs, CA: 115° Phoenix: 115° (tied record set in 1985) Pueblo, CO: 100° Tucson: 107° Yuma, AZ: 116° Today was the 11th consecutive day on which the temperature reached 120° or above at Death Valley. It is the longest August stretch since August 6-17, 2012 when the mercury reached 120° or above on 12 consecutive days. Phoenix has an implied near 100% probability of having its warmest summer on record. Phoenix will likely finish with a summer mean temperature of 96.7° - 96.9°. The existing record is 95.1°, which was set in summer 2013 and tied in summer 2015. July 2020 was Phoenix's warmest month on record with a mean temperature of 98.9°. August 2020 could approach or exceed that figure. There is currently an implied 62% probability that August will exceed July's monthly record. The ENSO Region 1+2 anomaly was -1.1°C and the Region 3.4 anomaly was -0.8°C for the week centered around August 19. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.17°C and the ENSO Region 3.4 anomaly has averaged -0.55°C. Neutral-cool conditions will likely evolve into La Niña conditions during the fall. The SOI was +11.17. Today, the preliminary Arctic Oscillation (AO) figure was +0.793. On August 23, the MJO was unavailable. The MJO's recent passage through Phase 8 at an amplitude of 1.500 or above has been fairly uncommon during the August 10-25 timeframe. During the 1981-2019 period only 2002 and 2004 saw the MJO move through Phase 8 with an amplitude of 1.500 or above during this period. Both cases were followed by a warmer than normal September. Last year, the MJO went through a very strong passage through Phase 1 during the closing days of May. About four weeks later, a warmer than normal pattern locked in and predominated through early autumn. This year, the MJO was in Phase 1 for 3 consecutive days with an amplitude of 1.500 or above during the June 1-3 period. Last year, the SOI fell to -42.04 on June 22 when the MJO was in Phase 6. This year, the SOI plunged below -46.68 on June 5, its lowest level in more than three years. The dramatic plunge in the SOI could be the proverbial spark that kicks off a sequence of events leading to the development of a sustained warmer than normal period. The cases that saw both the MJO and SOI thresholds satisfied generally saw 10-20 days where the temperature reached or exceeded 90° in New York City during the July 1-August 31 period. Since 1990, there have been 11 La Niña events, 6 of which followed an El Niño winter. 10/11 (91%) case saw warmer than normal September. All 6 following an El Niño winter were warmer than normal. September mean temperatures for New York City for those cases were: 11 cases: 69.9°; Subset of 6 cases: 70.8°; Entire 1990-2019 period: 69.0°. The September mean temperature for all La Niña and neutral-cool cases following an El Niño winter (1950-2019: n=13) was 69.9°. Overall, the evolution of ENSO, along with the observed ongoing monthly warming (1.6°/decade in NYC and 1.5°/decade in the Northeast Region during September 1990-2019), favors a warmer than normal September. Since 1950, there have been five cases where a La Niña developed during June-July-August or afterward following an El Niño winter. 4/5 (80%) of those cases saw a predominant EPO+/AO+ winter pattern. The most recent such case was 2016-17. 9/10 (90%) of the La Niña winters that followed an El Niño winter featured a predominantly positive EPO. Based on sensitivity analysis applied to the latest guidance, there is an implied 92% probability that New York City will have a warmer than normal August. August will likely finish with a mean temperature near 76.9°. Finally, on August 23, Arctic sea ice extent was 4.266 million square kilometers (JAXA). There is an implied 91% probability that Arctic sea ice extent will reach a minimum figure below 4.000 million square kilometers for the second consecutive year and third time on record. The highest 25% bound is 3.825 million square kilometers. The lowest 25% bound is 3.473 million square kilometers.

Almost certainly, climate change has driven the increased incidence of wildfires on a global basis. Brazil’s deliberate policy of land clearing in and around the Amazon has amplified the situation there. In fact, as the Amazon is reduced in size, that development will feedback in greater drying due to the loss of rainforest and increased fire risks.

Temperatures rose into the middle and even upper 80s across most of the region today. A thick line of severe thunderstorms moved across parts of Massachusetts late in the day with wind gusts in excess of 60 mph and hail. Through 8:05 pm, Boston picked up 1.30" rain. Worcester received 1.72" rain, which surpass the previous daily record of 1.33" from 1970. Tomorrow and Tuesday could see readings approach or reach 90° in much of the region. There is a risk of strong to possibly severe thunderstorms tomorrow and Tuesday. The month could end on a cool note before temperatures return to above normal levels during the first week of September. In addition, the remnants of Laura could exit off the Middle Atlantic coast late this week. The current predominantly warmer than normal pattern will likely persist through much of September, paving the way for a solidly warmer than normal summer and a warm start to fall throughout the region. Occasional short-lived cool shots remain possible. Parts of the West continued to experience near record to record warmth. Select high temperatures included: Death Valley, CA: 121° Denver: 98° (Tied record set in 2009 and tied in 2011) Flagstaff: 88° Lake Havasu City, AZ: 111° Las Vegas: 105° Needles, CA: 113° Palm Springs, CA: 113° Phoenix: 110° Pueblo, CO: 99° Tucson: 106° Yuma, AZ: 110° At Death Valley, the temperature topped out at 121°. That was the 10th consecutive day on which the temperature reached 120° or above and is the longest August stretch since August 6-17, 2012 when the mercury reached 120° or above on 12 consecutive days. Phoenix has an implied near 100% probability of having its warmest summer on record. Phoenix will likely finish with a summer mean temperature of 96.6° - 97.0°. The existing record is 95.1°, which was set in summer 2013 and tied in summer 2015. July 2020 was Phoenix's warmest month on record with a mean temperature of 98.9°. August 2020 could approach or exceed that figure. There is currently an implied 61% probability that August will exceed July's monthly record. The ENSO Region 1+2 anomaly was -0.9°C and the Region 3.4 anomaly was -0.5°C for the week centered around August 12. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.17°C and the ENSO Region 3.4 anomaly has averaged -0.45°C. Neutral-cool conditions will likely into the start of autumn. During the autumn, La Niña conditions will likely develop. The SOI was +9.53. Today, the preliminary Arctic Oscillation (AO) figure was +0.258. On August 22, the MJO was in Phase 1 at an amplitude of 1.700 (RMM). The August 21-adjusted amplitude was 1.529. The MJO's recent passage through Phase 8 at an amplitude of 1.500 or above has been fairly uncommon during the August 10-25 timeframe. During the 1981-2019 period only 2002 and 2004 saw the MJO move through Phase 8 with an amplitude of 1.500 or above during this period. Both cases were followed by a warmer than normal September. Last year, the MJO went through a very strong passage through Phase 1 during the closing days of May. About four weeks later, a warmer than normal pattern locked in and predominated through early autumn. This year, the MJO was in Phase 1 for 3 consecutive days with an amplitude of 1.500 or above during the June 1-3 period. Last year, the SOI fell to -42.04 on June 22 when the MJO was in Phase 6. This year, the SOI plunged below -46.68 on June 5, its lowest level in more than three years. The dramatic plunge in the SOI could be the proverbial spark that kicks off a sequence of events leading to the development of a sustained warmer than normal period. The cases that saw both the MJO and SOI thresholds satisfied generally saw 10-20 days where the temperature reached or exceeded 90° in New York City during the July 1-August 31 period. Since 1990, there have been 11 La Niña events, 6 of which followed an El Niño winter. 10/11 (91%) case saw warmer than normal September. All 6 following an El Niño winter were warmer than normal. September mean temperatures for New York City for those cases were: 11 cases: 69.9°; Subset of 6 cases: 70.8°; Entire 1990-2019 period: 69.0°. The September mean temperature for all La Niña and neutral-cool cases following an El Niño winter (1950-2019: n=13) was 69.9°. Overall, the evolution of ENSO, along with the observed ongoing monthly warming (1.6°/decade in NYC and 1.5°/decade in the Northeast Region during September 1990-2019), favors a warmer than normal September. Since 1950, there have been five cases where a La Niña developed during June-July-August or afterward following an El Niño winter. 4/5 (80%) of those cases saw a predominant EPO+/AO+ winter pattern. The most recent such case was 2016-17. 9/10 (90%) of the La Niña winters that followed an El Niño winter featured a predominantly positive EPO. Based on sensitivity analysis applied to the latest guidance, there is an implied 87% probability that New York City will have a warmer than normal August. August will likely finish with a mean temperature near 76.9°. Finally, on August 22, Arctic sea ice extent was 4.317 million square kilometers (JAXA). There is an implied 89% probability that Arctic sea ice extent will reach a minimum figure below 4.000 million square kilometers for the second consecutive year and third time on record. The highest 25% bound is 3.840 million square kilometers. The lowest 25% bound is 3.460 million square kilometers.

There's a growing body of literature linking climate change to a slowing of the jet stream. The end result is "stuck patterns." Alaska's record warm summer last year, Siberia's record warmth earlier this year, and Phoenix's record-setting summer this year are some recent examples resulting from a greater persistence in prevailing patterns.

BDL had yet another 90 degree day.

This PBS Newshour interview was conducted in 2018 but is as timely now as it was then. Since then, Australia recorded its worst fire season on record. More big wildfires are currently burning in California. https://www.pbs.org/newshour/show/climate-change-is-making-wildfires-more-extreme-heres-how And an animated satellite photo from the August 2020 fires in California:

Under mainly sunny skies, temperatures rose to the middle and upper 80s today. A few parts of the region reached 90° or slightly above. 90° Days for Select Cities (through August 22): Albany: 13 (2019: 12 days) Allentown: 23 (2019: 24 days) Baltimore: 40 (2019: 59 days) Boston: 14 (2019: 15 days) Burlington: 20 (2019: 8 days) Harrisburg: 30 (2019: 33 days) Hartford: 37 (2019: 27 days) Islip: 6 (2019: 8 days) New York City-JFK: 10 (2019: 7 days) New York City-LGA: 31 (2019: 26 days) New York City-NYC: 18 (2019: 15 days) Newark: 28 (2019: 28 days) Philadelphia: 32 (2019: 35 days) Scranton: 24 (2019: 12 days) Washington, DC: 41 (2019: 62 days) New York City-Newark Average: 22 (2019: 19 days) ...Expected: 22 (based on regression equation tied to JFK-LGA-EWR data) Tomorrow will be another warm day. At the height of the warmth early next week, readings could approach or reach 90° in much of the region. However, the month could end on a cool note before temperatures return to above normal levels during the first week of September. In addition, the remnants of Laura could exit off the Middle Atlantic coast late next week. The current predominantly warmer than normal pattern will likely persist through much of September, paving the way for a solidly warmer than normal summer and a warm start to fall throughout the region. Occasional short-lived cool shots remain possible. Parts of the West continued to experience near record to record warmth. Select high temperatures included: Death Valley, CA: 121° Denver: 97° Flagstaff: 90° (old record: 88°, 1938) Las Vegas: 105° Needles, CA: 111° Phoenix: 106° Pueblo, CO: 103° (old record: 100°, 2003 and 2013) ***hottest so late in the season*** At Death Valley, the temperature topped out at 120°. That was also the 9th consecutive day on which the temperature reached 120° or above. That is the longest August stretch since August 6-17, 2012 when the mercury reached 120° or above on 12 consecutive days. Phoenix has an implied near 100% probability of having its warmest summer on record. Phoenix will likely finish with a summer mean temperature of 96.6° - 97.0°. The existing record is 95.1°, which was set in summer 2013 and tied in summer 2015. July 2020 was Phoenix's warmest month on record with a mean temperature of 98.9°. August 2020 could approach or exceed that figure. There is currently an implied 56% probability that August will exceed July's monthly record. As recently, as 2000, the 30-year average summer minimum temperature in Phoenix was 79.8°. The last time Phoenix had an average summer minimum temperature below 80.0° was 1998 when the average minimum temperature was 79.7°. The first time Phoenix recorded an average summer mean temperature of 80° or above was in 1977 when the average low temperature was 81.5°. Records go back to August 1895. The ENSO Region 1+2 anomaly was -0.9°C and the Region 3.4 anomaly was -0.5°C for the week centered around August 12. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.17°C and the ENSO Region 3.4 anomaly has averaged -0.45°C. Neutral-cool conditions will likely into the start of autumn. During the autumn, La Niña conditions will likely develop. The SOI was +9.53. Today, the preliminary Arctic Oscillation (AO) figure was -0.397. On August 21, the MJO was in Phase 1 at an amplitude of 1.533 (RMM). The August 20-adjusted amplitude was 1.572. The MJO's recent passage through Phase 8 at an amplitude of 1.500 or above has been fairly uncommon during the August 10-25 timeframe. During the 1981-2019 period only 2002 and 2004 saw the MJO move through Phase 8 with an amplitude of 1.500 or above during this period. Both cases were followed by a warmer than normal September. Last year, the MJO went through a very strong passage through Phase 1 during the closing days of May. About four weeks later, a warmer than normal pattern locked in and predominated through early autumn. This year, the MJO was in Phase 1 for 3 consecutive days with an amplitude of 1.500 or above during the June 1-3 period. Last year, the SOI fell to -42.04 on June 22 when the MJO was in Phase 6. This year, the SOI plunged below -46.68 on June 5, its lowest level in more than three years. The dramatic plunge in the SOI could be the proverbial spark that kicks off a sequence of events leading to the development of a sustained warmer than normal period. The cases that saw both the MJO and SOI thresholds satisfied generally saw 10-20 days where the temperature reached or exceeded 90° in New York City during the July 1-August 31 period. Since 1990, there have been 11 La Niña events, 6 of which followed an El Niño winter. 10/11 (91%) case saw warmer than normal September. All 6 following an El Niño winter were warmer than normal. September mean temperatures for New York City for those cases were: 11 cases: 69.9°; Subset of 6 cases: 70.8°; Entire 1990-2019 period: 69.0°. The September mean temperature for all La Niña and neutral-cool cases following an El Niño winter (1950-2019: n=13) was 69.9°. Overall, the evolution of ENSO, along with the observed ongoing monthly warming (1.6°/decade in NYC and 1.5°/decade in the Northeast Region during September 1990-2019), favors a warmer than normal September. Since 1950, there have been five cases where a La Niña developed during June-July-August or afterward following an El Niño winter. 4/5 (80%) of those cases saw a predominant EPO+/AO+ winter pattern. The most recent such case was 2016-17. 9/10 (90%) of the La Niña winters that followed an El Niño winter featured a predominantly positive EPO. Based on sensitivity analysis applied to the latest guidance, there is an implied 88% probability that New York City will have a warmer than normal August. August will likely finish with a mean temperature near 76.9°. Finally, on August 21, Arctic sea ice extent was 4.386 million square kilometers (JAXA). There is an implied 86% probability that Arctic sea ice extent will reach a minimum figure below 4.000 million square kilometers for the second consecutive year and third time on record. The highest 25% bound is 3.870 million square kilometers. The lowest 25% bound is 3.460 million square kilometers.

Unfortunately, based on 2010-19 melt rates, it is very likely that 2020 will finish solidly with the second lowest minimum extent on record. It will also be the second consecutive year with a minimum extent below 4 million square kilometers and third such year on record.

Temperatures topped out mainly in the lower 80s across the region today. Tomorrow will see noticeably warmer weather begin to overspread the region. At the height of the warmth, readings could approach or reach 90° in much of the region early next week. However, the month could end on a cool note before temperatures recover to above normal levels. The current predominantly warmer than normal pattern will likely persist through much of September, paving the way for a solidly warmer than normal summer and a warm start to fall throughout the region. Occasional short-lived cool shots remain possible. Although cooler readings prevailed in the Southwest today, Las Vegas reached 111°. That surpassed the daily record of 110°, which was set in 2009. At Death Valley, the temperature topped out at 124°. That surpassed the prior daily record of 122°, which was set in 1992. Today was also the 8th consecutive day on which the temperature reached 120° or above. That is the longest August stretch since August 6-17, 2012 when the mercury reached 120° or above on 12 consecutive days. Phoenix has an implied near 100% probability of having its warmest summer on record. Phoenix will likely finish with a summer mean temperature of 96.5° - 96.9°. The existing record is 95.1°, which was set in summer 2013 and tied in summer 2015. July 2020 was Phoenix's warmest month on record with a mean temperature of 98.9°. August 2020 could approach or exceed that figure. Since recordkeeping began in August 1895, two years saw both July and August rank among Phoenix's 20 warmest months on record: 2007 and 2019. It is all but certain that 2020 will become the third such case. The ENSO Region 1+2 anomaly was -0.9°C and the Region 3.4 anomaly was -0.5°C for the week centered around August 12. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.17°C and the ENSO Region 3.4 anomaly has averaged -0.45°C. Neutral-cool conditions will likely into the start of autumn. During the autumn, La Niña conditions will likely develop. The SOI was +23.79. Today, the preliminary Arctic Oscillation (AO) figure was -1.058. On August 20, the MJO was in Phase 8 at an amplitude of 1.567 (RMM). The August 19-adjusted amplitude was 1.470. The MJO's recent passage through Phase 8 at an amplitude of 1.500 or above has been fairly uncommon during the August 10-25 timeframe. During the 1981-2019 period only 2002 and 2004 saw the MJO move through Phase 8 with an amplitude of 1.500 or above during this period. Both cases were followed by a warmer than normal September. Last year, the MJO went through a very strong passage through Phase 1 during the closing days of May. About four weeks later, a warmer than normal pattern locked in and predominated through early autumn. This year, the MJO was in Phase 1 for 3 consecutive days with an amplitude of 1.500 or above during the June 1-3 period. Last year, the SOI fell to -42.04 on June 22 when the MJO was in Phase 6. This year, the SOI plunged below -46.68 on June 5, its lowest level in more than three years. The dramatic plunge in the SOI could be the proverbial spark that kicks off a sequence of events leading to the development of a sustained warmer than normal period. The cases that saw both the MJO and SOI thresholds satisfied generally saw 10-20 days where the temperature reached or exceeded 90° in New York City during the July 1-August 31 period. Since 1990, there have been 11 La Niña events, 6 of which followed an El Niño winter. 10/11 (91%) case saw warmer than normal September. All 6 following an El Niño winter were warmer than normal. September mean temperatures for New York City for those cases were: 11 cases: 69.9°; Subset of 6 cases: 70.8°; Entire 1990-2019 period: 69.0°. The September mean temperature for all La Niña and neutral-cool cases following an El Niño winter (1950-2019: n=13) was 69.9°. Overall, the evolution of ENSO, along with the observed ongoing monthly warming (1.6°/decade in NYC and 1.5°/decade in the Northeast Region during September 1990-2019), favors a warmer than normal September. Since 1950, there have been five cases where a La Niña developed during June-July-August or afterward following an El Niño winter. 4/5 (80%) of those cases saw a predominant EPO+/AO+ winter pattern. The most recent such case was 2016-17. 9/10 (90%) of the La Niña winters that followed an El Niño winter featured a predominantly positive EPO. Based on sensitivity analysis applied to the latest guidance, there is an implied 79% probability that New York City will have a warmer than normal August. August will likely finish with a mean temperature near 76.9°. Finally, on August 20, Arctic sea ice extent was 4.485 million square kilometers (JAXA). Recent days have seen an increase in the melt rate. There is an implied 81% probability that Arctic sea ice extent will reach a minimum figure below 4.000 million square kilometers for the second consecutive year and third time on record. The highest 25% bound is 3.938 million square kilometers. The lowest 25% bound is 3.503 million square kilometers.

Yes. It was 46 at MPO. It has been dry in the Southwest. However, Phoenix was hit by heavy thunderstorms last night with 0.90” rain.

The coolest temperatures since mid-June covered many parts of the area. Low temperatures included: Albany: 48° (coolest since June 14: 43°) Allentown: 54° (coolest since June 17: 53°) Boston: 61° (coolest since July 17: 59°) Bridgeport: 61° (coolest since June 17: 58°) Islip: 60° (coolest since June 17: 56°) New York City: 62° (coolest since June 17: 60°) Newark: 61° (coolest since June 17: 60°) Philadelphia: 64° (coolest since August 17: 63°) Poughkeepsie: 50° (coolest since June 16: 49°) Noticeably warmer weather will likely arrive this weekend. Readings could approach or reach 90° in much of the region early next week. Temperatures remained warmer than normal in many parts of the Southwest, even as temperatures backed off their recent extreme levels. Select high temperatures included: Death Valley, CA: 122° Flagstaff: 89° Kingman, AZ: 107° (tied record set in 1915) Lake Havasu City, AZ: 115° Las Vegas: 112° (old record: 110°, 1950) Mesa, AZ: 109° Needles, CA: 118° Palm Springs, CA: 109° Phoenix: 112° Stockton, CA: 97° Tucson: 107° Yuma, AZ: 107° Phoenix has an implied 99% probability of having its warmest summer on record. Phoenix will likely finish with a summer mean temperature of 96.5° - 96.9°. The existing record is 95.1°, which was set in summer 2013 and tied in summer 2015. July 2020 was Phoenix's warmest month on record with a mean temperature of 98.9°. Since recordkeeping began in August 1895, two years saw both July and August rank among Phoenix's 20 warmest months on record: 2007 and 2019. It is all but certain that 2020 will become the third such case. Consistent with the forecasts related to climate change, Phoenix has been witnessing an increased number of annual days on which the temperature reaches 100° or above and on which the low temperature remains at or above 90°. For the 30-year period ending in 1999, Phoenix averaged 100.1 days per year with maximum temperatures of 100° or above and 1.1 days per year on which the minimum temperature was 90° or above. For the 30-year period ending in 2019, those increased to 109.6 days per year and 6.6 days per year respectively. The current predominantly warmer than normal pattern will likely persist through much of September, paving the way for a solidly warmer than normal summer and a warm start to fall throughout the region. Occasional short-lived cool shots remain possible. The ENSO Region 1+2 anomaly was -0.9°C and the Region 3.4 anomaly was -0.5°C for the week centered around August 12. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.17°C and the ENSO Region 3.4 anomaly has averaged -0.45°C. Neutral-cool conditions will likely into the start of autumn. During the autumn, La Niña conditions will likely develop. The SOI was +26.40. Today, the preliminary Arctic Oscillation (AO) figure was -1.330. On August 19, the MJO was in Phase 8 at an amplitude of 1.470 (RMM). The August 18-adjusted amplitude was 1.700. The MJO's recent passage through Phase 8 at an amplitude of 1.500 or above has been fairly uncommon during the August 10-25 timeframe. During the 1981-2019 period only 2002 and 2004 saw the MJO move through Phase 8 with an amplitude of 1.500 or above during this period. Both cases were followed by a warmer than normal September. Last year, the MJO went through a very strong passage through Phase 1 during the closing days of May. About four weeks later, a warmer than normal pattern locked in and predominated through early autumn. This year, the MJO was in Phase 1 for 3 consecutive days with an amplitude of 1.500 or above during the June 1-3 period. Last year, the SOI fell to -42.04 on June 22 when the MJO was in Phase 6. This year, the SOI plunged below -46.68 on June 5, its lowest level in more than three years. The dramatic plunge in the SOI could be the proverbial spark that kicks off a sequence of events leading to the development of a sustained warmer than normal period. The cases that saw both the MJO and SOI thresholds satisfied generally saw 10-20 days where the temperature reached or exceeded 90° in New York City during the July 1-August 31 period. Since 1990, there have been 11 La Niña events, 6 of which followed an El Niño winter. 10/11 (91%) case saw warmer than normal September. All 6 following an El Niño winter were warmer than normal. September mean temperatures for New York City for those cases were: 11 cases: 69.9°; Subset of 6 cases: 70.8°; Entire 1990-2019 period: 69.0°. The September mean temperature for all La Niña and neutral-cool cases following an El Niño winter (1950-2019: n=13) was 69.9°. Overall, the evolution of ENSO, along with the observed ongoing monthly warming (1.6°/decade in NYC and 1.5°/decade in the Northeast Region during September 1990-2019), favors a warmer than normal September. Since 1950, there have been five cases where a La Niña developed during June-July-August or afterward following an El Niño winter. 4/5 (80%) of those cases saw a predominant EPO+/AO+ winter pattern. The most recent such case was 2016-17. 9/10 (90%) of the La Niña winters that followed an El Niño winter featured a predominantly positive EPO. Based on sensitivity analysis applied to the latest guidance, there is an implied 80% probability that New York City will have a warmer than normal August. August will likely finish with a mean temperature near 77.0°.

Another short-lived cool shot is overspreading the region in the wake of the showers and thundershowers and moved across the area earlier today. Overnight, parts of the region could see their coolest readings so far this month. Noticeably warmer weather will likely arrive this weekend. Readings could approach or reach 90° in much of the region early next week. Out west, extreme heat again prevailed in the Southwest. Select high temperatures included: Blythe, CA: 116° (old record: 114°, 1973) Death Valley, CA: 125° (tied record set in 2001) Flagstaff: 89° (old record: 88°, 1928 and 1973) Kingman, AZ: 107° Lake Havasu City, AZ: 117° (old record: 116°, 2011) Las Vegas: 113° (old record: 111°, 1937 and 1992) Mesa, AZ: 112° (old record: 108°, 2019) Needles, CA: 118° (old record: 117°, 2018) Palm Springs, CA: 114° Phoenix: 115° (old record: 113°, 1986) Sacramento: 101° Stockton, CA: 105° Tucson, AZ: 111° (old record: 110°, 1915) Yuma, AZ: 112° Death Valley reached 125° or above for the fifth consecutive day. That further extended its August record streak. The previous August record of three days was set during August 11-13, 1933 and tied during August 6-8, 1998. In addition, Phoenix has now registered a record-tying four consecutive days with temperatures of 115° or above for the second time this summer. No previous year had more than one such stretch. Phoenix has an implied 98% probability of having its warmest summer on record. Phoenix will likely finish with a summer mean temperature of 96.5° - 96.9°. The existing record is 95.1°, which was set in summer 2013 and tied in summer 2015. July 2020 was Phoenix's warmest month on record with a mean temperature of 98.9°. Since recordkeeping began in August 1895, two years saw both July and August rank among Phoenix's 20 warmest months on record: 2007 and 2019. It is all but certain that 2020 will become the third such case. The current predominantly warmer than normal pattern will likely persist through much of September, paving the way for a solidly warmer than normal summer and a warm start to fall throughout the region. Occasional short-lived cool shots remain possible. The ENSO Region 1+2 anomaly was -0.9°C and the Region 3.4 anomaly was -0.5°C for the week centered around August 12. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.17°C and the ENSO Region 3.4 anomaly has averaged -0.45°C. Neutral-cool conditions will likely into the start of autumn. During the autumn, La Niña conditions will likely develop. The SOI was +28.46. That was the highest SOI figure since April 2, 2018 when the SOI was +31.29. Today, the preliminary Arctic Oscillation (AO) figure was -1.394. On August 18, the MJO was in Phase 8 at an amplitude of 1.698 (RMM). The August 17-adjusted amplitude was 1.835. The MJO's recent passage through Phase 8 at an amplitude of 1.500 or above has been fairly uncommon during the August 10-25 timeframe. During the 1981-2019 period only 2002 and 2004 saw the MJO move through Phase 8 with an amplitude of 1.500 or above during this period. Both cases were followed by a warmer than normal September. Last year, the MJO went through a very strong passage through Phase 1 during the closing days of May. About four weeks later, a warmer than normal pattern locked in and predominated through early autumn. This year, the MJO was in Phase 1 for 3 consecutive days with an amplitude of 1.500 or above during the June 1-3 period. Last year, the SOI fell to -42.04 on June 22 when the MJO was in Phase 6. This year, the SOI plunged below -46.68 on June 5, its lowest level in more than three years. The dramatic plunge in the SOI could be the proverbial spark that kicks off a sequence of events leading to the development of a sustained warmer than normal period. The cases that saw both the MJO and SOI thresholds satisfied generally saw 10-20 days where the temperature reached or exceeded 90° in New York City during the July 1-August 31 period. Since 1990, there have been 11 La Niña events, 6 of which followed an El Niño winter. 10/11 (91%) case saw warmer than normal September. All 6 following an El Niño winter were warmer than normal. September mean temperatures for New York City for those cases were: 11 cases: 69.9°; Subset of 6 cases: 70.8°; Entire 1990-2019 period: 69.0°. The September mean temperature for all La Niña and neutral-cool cases following an El Niño winter (1950-2019: n=13) was 69.9°. Overall, the evolution of ENSO, along with the observed ongoing monthly warming (1.6°/decade in NYC and 1.5°/decade in the Northeast Region during September 1990-2019), favors a warmer than normal September. Since 1950, there have been five cases where a La Niña developed during June-July-August or afterward following an El Niño winter. 4/5 (80%) of those cases saw a predominant EPO+/AO+ winter pattern. The most recent such case was 2016-17. 9/10 (90%) of the La Niña winters that followed an El Niño winter featured a predominantly positive EPO. Based on sensitivity analysis applied to the latest guidance, there is an implied 83% probability that New York City will have a warmer than normal August. August will likely finish with a mean temperature near 77.0°.

That is Newark’s latest 100 degree reading.

Morning thoughts... At 7:50 am, a shower was crossing the Hudson River just north of Yonkers and a thundershower was approaching Englewood. A larger area of showers and thundershowers covered an area running from northern Virginia to eastern Pennsylvania. That area as headed northeastward and will likely affect the Philadelphia, Newark and New York City areas later this morning. Sunshine should return to those areas during the afternoon. In the wake of the frontal passage, tonight will see temperatures fall into the lower 60s in New York City and 50s in many places outside the City. Out west, intense heat will again topple records in parts of California, Arizona and Nevada. Out in the eastern Atlantic, a new tropical depression could develop in over the next 24-48 hours.

July 2020 was also Phoenix’s hottest month on record by 0.6 degrees.

The region saw its coolest readings since just after mid-June this morning. During the afternoon, the temperature rebounded into the lower and middle 80s. Another brief cool shot is possible near mid-week. Noticeably warmer weather could arrive for the weekend. Out west, extreme heat again prevailed in the Southwest. Select high temperatures included: Death Valley, CA: 126° (old record: 124°, 2001) Flagstaff: 88° (old record: 87°, 1992 and 2002) Kingman, AZ: 110° (old record: 109°, 1915) Lake Havasu City, AZ: 115° Las Vegas: 114° (old record: 111°, 1992) Mesa, AZ: 111° (old record: 102°, 2019) Needles, CA: 118° (old record: 115°, 1992 and 2011) Palm Springs, CA: 114° Phoenix: 115° (old record: 112°, 2011) Sacramento: 106° Stockton, CA: 107° (tied record set in 1967) Tucson, AZ: 107° (old record: 107°, 2013) Yuma, AZ: 111° Death Valley reached 125° or above for the fourth consecutive day. That surpassed the previous August record, which was set during August 11-13, 1933 and tied during August 6-8, 1998. Intense heat will likely continue in that region into the coming weekend although the most severe heat will fade after midweek. Phoenix has an implied 97% probability of having its warmest summer on record. Phoenix will likely finish with a summer mean temperature of 96.4° - 96.8°. The existing record is 95.1°, which was set in summer 2013 and tied in summer 2015. July 2020 was Phoenix's warmest month on record with a mean temperature of 98.9°. Since recordkeeping began in August 1895, two years saw both July and August rank among Phoenix's 20 warmest months on record: 2007 and 2019. It is all but certain that 2020 will become the third such case. The current predominantly warmer than normal pattern will likely persist through much of September, paving the way for a solidly warmer than normal summer and a warm start to fall throughout the region. Occasional short-lived cool shots remain possible. The ENSO Region 1+2 anomaly was -0.9°C and the Region 3.4 anomaly was -0.5°C for the week centered around August 12. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.17°C and the ENSO Region 3.4 anomaly has averaged -0.45°C. Neutral-cool conditions will likely into the start of autumn. During the autumn, La Niña conditions will likely develop. The SOI was +10.56. Today, the preliminary Arctic Oscillation (AO) figure was -1.377. On August 17, the MJO was in Phase 8 at an amplitude of 1.837 (RMM). The August 16-adjusted amplitude was 1.632. The MJO's recent passage through Phase 4 at an amplitude of 1.500 or above has been uncommon during the first half of August. During the 1981-2019 period only 1983 and 2019 saw the MJO move through Phase 4 with an amplitude of 1.500 or above during the first half of August. August 1983 had the longest such stretch. Both cases saw the second half of August average generally warmer than normal in the Middle Atlantic region. Both cases also featured a warmer than normal September. Last year, the MJO went through a very strong passage through Phase 1 during the closing days of May. About four weeks later, a warmer than normal pattern locked in and predominated through early autumn. This year, the MJO was in Phase 1 for 3 consecutive days with an amplitude of 1.500 or above during the June 1-3 period. Last year, the SOI fell to -42.04 on June 22 when the MJO was in Phase 6. This year, the SOI plunged below -46.68 on June 5, its lowest level in more than three years. The dramatic plunge in the SOI could be the proverbial spark that kicks off a sequence of events leading to the development of a sustained warmer than normal period. The cases that saw both the MJO and SOI thresholds satisfied generally saw 10-20 days where the temperature reached or exceeded 90° in New York City during the July 1-August 31 period. Since 1990, there have been 11 La Niña events, 6 of which followed an El Niño winter. 10/11 (91%) case saw warmer than normal September. All 6 following an El Niño winter were warmer than normal. September mean temperatures for New York City for those cases were: 11 cases: 69.9°; Subset of 6 cases: 70.8°; Entire 1990-2019 period: 69.0°. The September mean temperature for all La Niña and neutral-cool cases following an El Niño winter (1950-2019: n=13) was 69.9°. Overall, the evolution of ENSO, along with the observed ongoing monthly warming (1.6°/decade in NYC and 1.5°/decade in the Northeast Region during September 1990-2019), favors a warmer than normal September. Since 1950, there have been five cases where a La Niña developed during June-July-August or afterward following an El Niño winter. 4/5 (80%) of those cases saw a predominant EPO+/AO+ winter pattern. The most recent such case was 2016-17. 9/10 (90%) of the La Niña winters that followed an El Niño winter featured a predominantly positive EPO. Based on sensitivity analysis applied to the latest guidance, there is an implied 79% probability that New York City will have a warmer than normal August. August will likely finish with a mean temperature near 77.0°. Finally, on August 17, Arctic sea ice extent was 4.782 million square kilometers (JAXA). There is an implied 63% probability that Arctic sea ice extent will reach a minimum figure below 4.000 million square kilometers for the second consecutive year and third time on record. The highest 25% bound is 4.129 million square kilometers. The lowest 25% bound is 3.609 million square kilometers.

I tried to take it, but received the following message: This survey is now closed, but the Haz Simp team will still be accepting comments on the proposal via email ([email protected]) through August 21, 2020. Thank you for your interest!

Morning thoughts... It was another cool morning in parts of the region. At New York City, the temperature fell to 63 degrees, its coolest figure since June 17 when the temperature fell to 60 degrees. At Newark, the temperature fell to 63 degrees. The last time it was at least as cool there was on June 17 when the temperature dropped to 60 degrees. Under bright sunshine, temperatures will rebound to the lower and even middle 80s. After another short mid-week cool shot, noticeably warmer conditions will likely develop for the coming weekend. Out west, intense heat will again topple records in parts of California, Arizona and Nevada. Out in the eastern Atlantic, a new tropical depression could develop in coming days.

From this evening as a thunderstorm passed to the north of Larchmont. The Village received a downpour, but only a few drops fell right at the Long Island Sound.

The region saw its coolest readings since just after mid-June this morning. However, under sunshine, the temperature rebounded into the upper 70s and lower 80s. The day ended with scattered thunderstorms. Another brief cool shot is possible near mid-week before a more prolonged warming trend takes hold. Out west, extreme heat again prevailed in the Southwest. Select high temperatures included: Bishop, CA: 105° Blythe, CA: 117° (old record: 116°, 1950 and 1992) Death Valley, CA: 127° (old record: 125°, 1994) Flagstaff: 91° (old record: 88°, 2002) Kingman, AZ: 108° (old record: 106°, 2001) Lake Havasu City, AZ: 115° Las Vegas: 112° (old record: 111°, 1939) Mesa, AZ: 113° (old record: 106°, 2019) Needles, CA: 117° (tied record set in 1892) Palm Springs, CA: 114° Phoenix: 115° (old record: 114°, 2013) Sacramento: 105° Stockton, CA: 109° (old record: 106°, 1967) Tucson, AZ: 109° (old record: 108°, 2013) Yuma, AZ: 114° (tied record set in 1892 and tied in 1953 and 1992) Death Valley reached 125° or above for the third consecutive day. That ties the August record, which was set during August 11-13, 1933 and tied during August 6-8, 1998. Intense heat will likely continue in that region into the coming weekend although the most severe heat will fade after midweek. Phoenix has an implied 96% probability of having its warmest summer on record. Phoenix will likely finish with a summer mean temperature of 96.3° - 96.7°. The existing record is 95.1°, which was set in summer 2013 and tied in summer 2015. July 2020 was Phoenix's warmest month on record with a mean temperature of 98.9°. The current predominantly warmer than normal pattern will likely persist through much of September, paving the way for a solidly warmer than normal summer and a warm start to fall throughout the region. Occasional short-lived cool shots remain possible. The ENSO Region 1+2 anomaly was -0.9°C and the Region 3.4 anomaly was -0.5°C for the week centered around August 12. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.17°C and the ENSO Region 3.4 anomaly has averaged -0.45°C. Neutral-cool conditions will likely into the start of autumn. During the autumn, La Niña conditions will likely develop. The SOI was -3.52. Today, the preliminary Arctic Oscillation (AO) figure was -0.917. On August 16, the MJO was in Phase 8 at an amplitude of 1.635 (RMM). The August 15-adjusted amplitude was 1.367. The MJO's recent passage through Phase 4 at an amplitude of 1.500 or above has been uncommon during the first half of August. During the 1981-2019 period only 1983 and 2019 saw the MJO move through Phase 4 with an amplitude of 1.500 or above during the first half of August. August 1983 had the longest such stretch. Both cases saw the second half of August average generally warmer than normal in the Middle Atlantic region. Both cases also featured a warmer than normal September. Last year, the MJO went through a very strong passage through Phase 1 during the closing days of May. About four weeks later, a warmer than normal pattern locked in and predominated through early autumn. This year, the MJO was in Phase 1 for 3 consecutive days with an amplitude of 1.500 or above during the June 1-3 period. Last year, the SOI fell to -42.04 on June 22 when the MJO was in Phase 6. This year, the SOI plunged below -46.68 on June 5, its lowest level in more than three years. The dramatic plunge in the SOI could be the proverbial spark that kicks off a sequence of events leading to the development of a sustained warmer than normal period. The cases that saw both the MJO and SOI thresholds satisfied generally saw 10-20 days where the temperature reached or exceeded 90° in New York City during the July 1-August 31 period. Since 1990, there have been 11 La Niña events, 6 of which followed an El Niño winter. 10/11 (91%) case saw warmer than normal September. All 6 following an El Niño winter were warmer than normal. September mean temperatures for New York City for those cases were: 11 cases: 69.9°; Subset of 6 cases: 70.8°; Entire 1990-2019 period: 69.0°. The September mean temperature for all La Niña and neutral-cool cases following an El Niño winter (1950-2019: n=13) was 69.9°. Overall, the evolution of ENSO, along with the observed ongoing monthly warming (1.6°/decade in NYC and 1.5°/decade in the Northeast Region during September 1990-2019), favors a warmer than normal September. Since 1950, there have been five cases where a La Niña developed during June-July-August or afterward following an El Niño winter. 4/5 (80%) of those cases saw a predominant EPO+/AO+ winter pattern. The most recent such case was 2016-17. 9/10 (90%) of the La Niña winters that followed an El Niño winter featured a predominantly positive EPO. Based on sensitivity analysis applied to the latest guidance, there is an implied 74% probability that New York City will have a warmer than normal August. August will likely finish with a mean temperature near 77.0°.