donsutherland1

Morning thoughts... This morning, temperatures were in the 50s across the region. 7 am temperatures included: Albany: 50°; Allentown: 51°; Bridgeport: 58°; Islip: 57°; New York City: 57°; Newark: 57°; Philadelphia: 57°; Poughkeepsie: 52°; and White Plains: 55°. Brilliant sunshine will be accompanied by a refreshing breeze. After a cool start, temperatures will likely reach the upper 70s in most places today. Likely high temperatures around the region include: New York City (Central Park): 77° Newark: 80° Philadelphia: 77° Normals: New York City: 30-Year: 82.0°; 15-Year: 81.9° Newark: 30-Year: 84.3°; 15-Year: 84.3° Philadelphia: 30-Year: 85.5°; 15-Year: 85.7° Tomorrow will be fair and pleasant. An extreme to perhaps historic heatwave will likely begin to descend on the Pacific Northwest on Friday. At its height numerous June and perhaps all-time high temperature records will tumble, including at Portland and Seattle.

Tomorrow and Thursday should feature abundant sunshine, low humidity, and refreshing temperatures. The end of the week and coming weekend will turn warmer. No excessive precipitation appears likely through the weekend. In the Pacific Northwest, an extreme to possibly historic heatwave could develop starting late this week. Monthly and possibly all-time record high temperatures in cities, including Seattle and Portland, could be challenged or broken. Climate change has increased the frequency, magnitude, and duration of extreme heat events in the United States and worldwide. Further increases are likely in coming decades as the world's climate continues to warm. In large part on account of Phoenix's recent extreme heat event, there is an implied 73% probability that June 2021 will become Phoenix's warmest June on record with a mean temperature above 95.0°. The existing record of 94.8° was set in 2013 and tied in 2016. The ENSO Region 1+2 anomaly was +0.4°C and the Region 3.4 anomaly was -0.5°C for the week centered around June 16. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.30°C and the ENSO Region 3.4 anomaly has averaged -0.25°C. Neutral ENSO conditions will likely prevail into at least mid-summer. The SOI was +1.05 today. The preliminary Arctic Oscillation (AO) figure was -0.182 today. On June 20 the MJO was in Phase 1 at an amplitude of 0.736 (RMM). The June 19-adjusted amplitude was 0.800 (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 86% probability that New York City will have a warmer than normal June (1991-2020 normal). June will likely finish with a mean temperature near 73.6° (1.6° above normal).

1911 and 1933 had at least one 100-degree day. 1900 and 1922 did not.

Unfortunately, the advance coverage in the Seattle Times omits the role climate change is playing in increasing the likelihood and severity of such events. https://www.seattletimes.com/seattle-news/weather/cooler-temps-arrive-tuesday-and-wednesday-but-seattle-could-see-100-degree-weekend/ Good coverage provides the “why,” which is more than the specific synoptic pattern.

Last year, Phoenix experienced a historically hot summer. Although the extreme heat held off through May this year, a severe heatwave developed toward mid-June. The June 2021 heatwave was among Phoenix's and Tucson's most severe June heatwaves and their most severe heatwave this early in the season. This heatwave developed as an extreme upper air ridge evolved during an era of rising June temperatures and an ongoing drought. An extreme heat event commenced at Tucson on June 11 and it commenced at Phoenix on June 13. Such events are likely to become even more frequent in the years ahead. Anthropogenic warming is creating a growing likelihood of long-duration extreme events through more frequent wave resonance events (Kornhuber et al., 2016 and Mann et al., 2017). Already, the frequency and intensity of compound summertime hot extremes (events that combine daytime and nighttime heat where such temperatures are above their 90th percentile for their calendar) has been increasing especially in geographic locations that include the U.S. Southwest (Wang 2020). The increase in forcing associated with anthropogenic greenhouse gases is the dominant driver of this outcome (Wang 2020). Table 1: Phoenix's High Temperatures during June 12-20, 2021 Table 2: Phoenix's Average June Temperatures (30-Year Moving Average) Table 3: Phoenix's Record High Maximum Temperatures Table 4: Phoenix's Record High Minimum Temperatures A portion of this heatwave qualified as the 8th Extreme Heat Event (EHE) on record for June, as at least 3 days saw the maximum , temperature exceed the 97.5th percentile (Phoenix: 115° or above; Tucson: 110° or above), the high temperature average exceeded the 97.5th percentile (Phoenix: 115° or above; Tucson: 110° or above), and all high temperatures exceeded the 81st percentile (Phoenix: 110° or above; Tucson: 105° or above) in June-August high temperatures for the 1971-2000 base period (Clarke, et al.,2014). The extreme heat event began on June 11 in Tucson and June 12 at Phoenix. Table 5: Phoenix's Extreme Heat Events in June (1896-2021) Additional Records: Earliest 116° or above high temperature: June 17, 2021 (old record: June 19, 2016 and 2017) Earliest 4 consecutive 115° days: June 15-18, 2021 (old record: June 19-22, 1968) Most consecutive 115° days: 6, June 15-20, 2021 (old record: 4, June 19-22, 1968; June 25-28, 1979; June 25-28, 1990; July 26-29, 1995; July 28-31, 2020; and, August 16-19, 2020) Earliest 4-day average high temperature of 115° or above: June 14-17, 2021 (old record: June 18-21, 2017) Earliest 5-day average high temperature of 115° or above: June 14-18, 2021 (old record: June 17-21, 2017) Earliest 6-day average high temperature of 115° or above: June 13-18, 2021 (old record: June 18-23, 2017) Earliest 7-day average high temperature of 115° or above: June 13-19, 2021 (old record: June 18-24, 2017) Earliest 8-day average high temperature of 115° or above: June 13-20, 2021 (old record: June 18-25, 2017) Earliest mean temperature of 100° or above: June 15, 2021 (old record: June 17, 2008) Earliest 2-day average mean temperature of 100° or above: June 15-16, 2021 (old record: June 17-18, 2008 and 2015) Earliest 3-day average mean temperature of 100° or above: June 14-16, 2021 (old record: June 17-19, 2015) Earliest 4-day average mean temperature of 100° or above: June 14-17, 2021 (old record: June 18-21, 2017) Earliest 5-day average mean temperature of 100° or above: June 13-17, 2021 (old record: June 18-22, 2017) Earliest 6-day average mean temperature of 100° or above: June 13-18, 2021 (old record: June 18-23, 2017) Earliest 7-day average mean temperature of 100° or above: June 13-19, 2021 (old record: June 18-24, 2017) Earliest 8-day average mean temperature of 100° or above: June 12-19, 2021 (old record: June 17-24, 2017) Earliest 91° minimum temperature: June 17, 2021 (old record: June 22, 2017) Earliest 92° minimum temperature: June 18, 2021 (old record: June 25, 2017) Earliest 2 consecutive 90° low temperatures: June 16-17, 2021 (old record: June 21-22, 2017) Earliest 3 consecutive 90° low temperatures: June 16-18, 2021 (old record: June 29-July 1, 2013) Earliest 4 consecutive 90° low temperatures: June 16-19, 2021 (old record: July 8-11, 2020) Most consecutive 90° low temperatures in June: 4, June 16-19, 2021 (old record: June 26-27, 1990; June 29-30, 2013; June 26-27, 2016; June 21-22, 2017; and, June 25-26, 2017) Earliest 2-day average low temperature of 90° or above: June 16-17, 2021 (old record: June 21-22, 2017) Earliest 3-day average low temperature of 90° or above: June 16-18, 2021 (old record: June 24-26, 2017) Earliest 4-day average low temperature of 90° or above: June 16-19, 2021 (old record: July 4-7, 2018) Earliest 5-day average low temperature of 90° or above: June 16-20, 2021 (old record: June 22-26, 2017) Earliest 6-day average low temperature of 90° or above: June 16-21, 2021 (old record: June 21-26, 2017) Highest average June minimum temperature after over 4 days: 91.0°, June 16-19, 2021 (old record: 89.8°, June 24-27, 1990; June 25-28, 1990; June 26-29, 1990; June 27-30, 1990; and, June 23-26, 2017) Highest average June minimum temperature after over 5 days: 90.6°, June 16-20, 2021 (old record: 90.0°, June 26-30, 1990 and June 22-26, 2017) Tucson also experienced extreme heat. As with Phoenix, Tucson has seen a steady increase in June minimum and maximum temperatures. This outcome has increased the statistical probability of extreme heat events. Table 1: Tucson's High Temperatures during the June 11-21, 2021 Heatwave Table 2: Tucson's Average June Temperatures (30-Year Moving Average) Table 3: Tucson's Record High Maximum Temperatures Table 4: Tucson's Record High Minimum Temperatures Table 5: Tucson's Extreme Heat Events in June Additional Records: Most consecutive days with high temperatures of 110° or above: 8, June 12-19, 2021 (old record: 6, June 24-29, 1994) Most consecutive days with high temperatures of 111° or above: 7, June 13-19, 2021 (old record: 6, June 24-29, 1994) Most consecutive days with high temperatures of 112° or above: 7, June 13-19, 2021 (old record: 4, June 25-28, 1990) Highest average high temperature over 8 days: 112.5°, June 12-19, 2021 (tied record set during June 23-30, 1994) Updates: Phoenix has its hottest June on record

Morning thoughts... Today will be variably cloudy and it will turn noticeably cooler. Showers and thundershowers are likely. Temperatures will likely reach the middle and upper 70s in most places this morning before falling sharply during the afternoon and evening hours. Likely high temperatures around the region include: New York City (Central Park): 75° Newark: 78° Philadelphia: 76° Normals: New York City: 30-Year: 81.7°; 15-Year: 81.6° Newark: 30-Year: 84.0°; 15-Year: 84.0° Philadelphia: 30-Year: 85.2°; 15-Year: 85.4° Tomorrow will be fair and pleasant.

If there were any question that the book’s author is profoundly out of touch with contemporary climate science understanding, this interview should erase all reasonable questions: https://www.foxnews.com/media/physicist-tells-tucker-carlson-climate-change-is-fiction-of-the-media.amp

Parts of the region again saw the temperature reach or exceed 90°. The heat will now depart through the remainder of the week. Tomorrow will be variably cloudy and noticeably cooler. Showers and thundershowers are likely. Wednesday and Thursday should feature abundant sunshine, low humidity, and refreshing temperatures. The end of the week and coming weekend could be unsettled. In large part on account of Phoenix's recent extreme heat event, there is an implied 70% probability that June 2021 will become Phoenix's warmest June on record with a mean temperature above 95.0°. The existing record of 94.8° was set in 2013 and tied in 2016. The ENSO Region 1+2 anomaly was +0.4°C and the Region 3.4 anomaly was -0.5°C for the week centered around June 16. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.30°C and the ENSO Region 3.4 anomaly has averaged -0.25°C. Neutral ENSO conditions will likely prevail into at least mid-summer. The SOI was -13.71 today. The preliminary Arctic Oscillation (AO) figure was -0.361 today. On June 19 the MJO was in Phase 2 at an amplitude of 0.809 (RMM). The June 18-adjusted amplitude was 1.068 (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 80% probability that New York City will have a warmer than normal June (1991-2020 normal). June will likely finish with a mean temperature near 73.5° (1.5° above normal).

Morning thoughts... Today will be variably cloudy and still very warm. Temperatures will likely reach the upper 80s in most places. A few places could reach 90°. Likely high temperatures around the region include: New York City (Central Park): 86° Newark: 92° Philadelphia: 90° Normals: New York City: 30-Year: 81.4°; 15-Year: 81.3° Newark: 30-Year: 83.7°; 15-Year: 83.7° Philadelphia: 30-Year: 85.0°; 15-Year: 85.2° Tomorrow will likely see more clouds, along with showers and thundershowers. It will be cooler.

A number of cities reached the lower 90s this afternoon. 90° readings included: Baltimore: 93°; Harrisburg: 91°; Newark: 90°; and, Philadelphia: 90°. 90° Days for Select Cities (through June 20): Albany: 1 (2020: 13 days; 5-Year Average: 13.6 days) Allentown: 5 (2020: 24 days; 5-Year Average: 27.6 days) Baltimore: 9 (2020: 46 days; 5-Year Average: 44.6 days) Boston: 8 (2020: 14 days; 5-Year Average: 17.2 days) Bridgeport: 2 (2020: 11 days; 5-Year Average: 13.4 days) Burlington: 4 (2020: 20 days; 5-Year Average: 13.0 days) Harrisburg: 6 (2020: 35 days; 5-Year Average: 30.6 days) Hartford: 7 (2020: 39 days; 5-Year Average: 29.0 days) Islip: 2 (2020: 8 days; 5-Year Average: 9.4 days) New York City-JFK: 3 (2020: 12 days; 5-Year Average: 10.2 days) New York City-LGA: 6 (2020: 34 days; 5-Year Average: 29.4 days) New York City-NYC: 4 (2020: 20 days; 5-Year Average: 18.2 days) Newark: 11 (2020: 31 days; 5-Year Average: 31.2 days) Philadelphia: 8 (2020: 36 days; 5-Year Average: 34.6 days) Scranton: 5 (2020: 25 days; 5-Year Average: 16.4 days) Washington, DC: 7 (2020: 46 days; 5-Year Average: 50.8 days) New York City-Newark Average: 6 (2020: 22 days) ...Expected: 7 (based on regression equation tied to JFK-LGA-EWR data) It will likely be somewhat cooler tomorrow with a greater risk of some showers and thundershowers as Claudette passes well south of the region. The end of the week and coming weekend could be unsettled. Out West, an extreme heatwave began to ease in the Southwest. High temperatures included: Blythe, CA: 119° Bullhead City, AZ: 117° Death Valley, CA: 124° ***June record 6th consecutive 124° day*** Las Vegas: 112° Needles, CA: 118° Palm Springs, CA: 118° Phoenix: 115° ***Record 6th consecutive 115° day*** Tucson: 109° In large part on account of Phoenix's concluding extreme heat event, there is an implied 69% probability that June 2021 will become Phoenix's warmest June on record with a mean temperature above 95.0°. The existing record of 94.8° was set in 2013 and tied in 2016. The ENSO Region 1+2 anomaly was 0.0°C and the Region 3.4 anomaly was 0.0°C for the week centered around June 9. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.48°C and the ENSO Region 3.4 anomaly has averaged -0.23°C. Neutral ENSO conditions will likely prevail into at least mid-summer. The SOI was -16.38 today. The preliminary Arctic Oscillation (AO) figure was +0.474 today. On June 18 the MJO was in Phase 2 at an amplitude of 1.073 (RMM). The June 17-adjusted amplitude was 1.198 (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 81% probability that New York City will have a warmer than normal June (1991-2020 normal). June will likely finish with a mean temperature near 73.7° (1.7° above normal).

Morning thoughts... Today will be partly cloudy and very warm. Temperatures will likely reach the upper 80s in most places. A few places could reach 90°. Likely high temperatures around the region include: New York City (Central Park): 87° Newark: 92° Philadelphia: 90° Normals: New York City: 30-Year: 81.1°; 15-Year: 81.0° Newark: 30-Year: 83.4°; 15-Year: 83.4° Philadelphia: 30-Year: 84.7°; 15-Year: 84.9° Tomorrow could see somewhat more clouds as Claudette passes well south of the region.

Temperatures rose into the upper 80s and lower 90s in the region today. 90° or above temperatures were reported at Boston (91°), New York City-LGA (91°), Newark (93°), and Philadelphia (90°). Tomorrow will be another variably cloudy and very warm day. The temperature could reach or exceed 90° in parts of the region. Some areas could see a shower or thunderstorm. It will likely be somewhat cooler on Monday with a greater risk of some showers and thundershowers as Claudette passes well south of the region. Out West, an extreme heatwave continued in the Southwest, including Phoenix. High temperatures included: Blythe, CA: 118° Bullhead City, AZ: 118° Death Valley, CA: 125° (tied record set in 2017) Las Vegas: 114° (tied record set in 1940) Needles, CA: 121° Palm Springs, CA: 119° (tied record set in 2016 and tied in 2017) Phoenix: 116° Sacramento: 102° Tucson: 113° Today, Phoenix recorded its 5th consecutive 115° or above temperature. That broke the record for most such days, which was 4. That record was set during June 19-22, 1968 and tied on June 25-28, 1979, June 25-28, 1990, July 26-29, 1995, July 28-31, 2020, and August 16-19, 2020. Tucson further extended its record streak of 110° or above days to 8. Death Valley recorded a June record-tying 5th consecutive day on which the temperature reached 124° or above. The record was set during June 26-30, 1994. Tomorrow will be another very hot day in the Southwest before some modest cooling takes place. Severe heat could return by the latter part of the week. In large part on account of Phoenix's concluding extreme heat event, there is an implied 66% probability that June 2021 will become Phoenix's warmest June on record with a mean temperature above 95.0°. The existing record of 94.8° was set in 2013 and tied in 2016. The ENSO Region 1+2 anomaly was 0.0°C and the Region 3.4 anomaly was 0.0°C for the week centered around June 9. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.48°C and the ENSO Region 3.4 anomaly has averaged -0.23°C. Neutral ENSO conditions will likely prevail into at least mid-summer. The SOI was -7.94 today. The preliminary Arctic Oscillation (AO) figure was +0.145 today. On June 17 the MJO was in Phase 2 at an amplitude of 1.200 (RMM). The June 16-adjusted amplitude was 1.457 (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 76% probability that New York City will have a warmer than normal June (1991-2020 normal). June will likely finish with a mean temperature near 73.8° (1.8° above normal).

At Phoenix, the preliminary low temperature was 91°. That would break the existing record highest minimum temperature for June 19, which is 86°. That record was set in 1958 and tied in 1959. Today's preliminary figure would also be the 4th consecutive minimum temperature of 90° or above. That would further extend this year's June record and would be the earliest 4 consecutive-day stretch on record. The existing record was set during July 8-11, 2020, the opening part of a all-time record-tying 7 consecutive days. The historically-hot summer of 2020 would go on to have a second 7-day stretch. 2020 saw a record 28 such days, which smashed the old record of 15 such days, which was set in 2003 and tied in 2013. Prior to 1934, Phoenix had never had such a high minimum temperature. It now averages 7.4 per year (1991-2020 climate period), which is up from 4.1 per year during the preceding climate period.

The "warming stripes" developed by Ed Hawkins to illustrate the impact of climate change depict how much warmer Phoenix has grown over the last 125 years.

Morning thoughts... Today will be partly cloudy and very warm. Temperatures will likely reach the upper 80s and even lower 90s in most places. A shower or thundershower is possible, especially during the afternoon or evening. Likely high temperatures around the region include: New York City (Central Park): 88° Newark: 93° Philadelphia: 89° Normals: New York City: 30-Year: 80.8°; 15-Year: 80.6° Newark: 30-Year: 83.1°; 15-Year: 83.1° Philadelphia: 30-Year: 84.4°; 15-Year: 84.6° Tomorrow will be another very warm day. Out West, record-breaking heat will continue across the Southwest, including Phoenix. Phoenix will likely record its record-breaking 5th consecutive day with temperatures reaching 115° or above. Daily Records for June 19: Phoenix: 118°, 2016 and 2017 (Forecast: 114° to 118°) Tucson: 115°, 2016 and 2017 (Forecast: 110° to 114°) *-Forecast range is 1 sigma below and above the forecast mean.

This weekend will be variably cloudy and very warm. The temperature could reach or exceed 90° in parts of the region. Some areas could see a shower or thunderstorm. Out West, an extreme heatwave continued in the Southwest, including Phoenix. High temperatures included: Blythe, CA: 119° (tied record set in 2015) Bullhead City, AZ: 120° (old record: 118°, 1985) Death Valley, CA: 124° (tied record set in 2017) Flagstaff: 91° Las Vegas: 113° Needles, CA: 121° (old record: 119°, 2017) Palm Springs, CA: 119° (old record: 117°, 2017) Phoenix: 117° (old record: 115°, 1989 and 2015) Sacramento: 109° (old record: 106°, 2017) Tucson: 112° Tucson reached 110° or above for the 7th consecutive day with a high temperature of 112°. That broke the old record of 6 consecutive days, which was set during June 24-29, 1994. Phoenix recorded a record-tying 4th consecutive day on which the temperature reached or exceeded 115°. This is also the earliest such stretch on record. The prior record was June 19-22, 1968. The most recent 4-day stretch occurred during 2020 (the only year with 2 such cases) during August 16-19, 2020. Death Valley recorded its 4th consecutive day with a high temperature of 124° or above. That was the earliest such streak on record. The prior record was June 26-29, 1994. The 4-day average high temperature was 125.3°. The previous earliest 4-day high temperature average of 125° or above occurred during June 22-25, 2017. The extreme heat will continue into the weekend. The temperature could reach 115° tomorrow and possibly Sunday in Phoenix. Phoenix's daily records for the June 19 are posted below. Record high maximum temperatures: June 19: 118°, 2016 and 2017 Record high minimum temperatures: June 19: 86°, 1958 and 1959 In large part on account of Phoenix's ongoing extreme heat event, there is an implied 55% probability that June 2021 will become Phoenix's warmest June on record with a mean temperature near or just above 95.0°. The existing record of 94.8° was set in 2013 and tied in 2016. The ENSO Region 1+2 anomaly was 0.0°C and the Region 3.4 anomaly was 0.0°C for the week centered around June 9. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.48°C and the ENSO Region 3.4 anomaly has averaged -0.23°C. Neutral ENSO conditions will likely prevail into at least mid-summer. The SOI was +2.04 today. The preliminary Arctic Oscillation (AO) figure was +0.474 today. On June 16 the MJO was in Phase 2 at an amplitude of 1.459 (RMM). The June 15-adjusted amplitude was 1.344 (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 81% probability that New York City will have a warmer than normal June (1991-2020 normal). June will likely finish with a mean temperature near 73.9° (1.9° above normal).

A useful paper that helps explain persistent sometimes extreme patterns: https://www.nature.com/articles/srep45242

Phoenix had a preliminary low temperature of 92°. That would easily surpass the existing record high minimum temperature of 88°, which was set in 2008. That would be the earliest 92° minimum temperature on record. The existing record was set on June 25, 2017. It would also be the 3rd consecutive 90° low temperature and the first 3-day stretch entirely in June. The earliest such streak occurred during June 29-July 1, 2013. Death Valley had a preliminary low temperature of 101°. That would smash the existing mark of 94°, which was set in 1961.

It could be the peak, though Death Valley might be exceptionally hot today and again tomorrow.

Morning thoughts... Today will be partly cloudy and noticeably warmer. Temperatures will likely reach the lower and middle 80s in most places. Likely high temperatures around the region include: New York City (Central Park): 84° Newark: 88° Philadelphia: 84° Normals: New York City: 30-Year: 80.6°; 15-Year: 80.4° Newark: 30-Year: 82.8°; 15-Year: 82.8° Philadelphia: 30-Year: 84.1°; 15-Year: 84.3° A very warm weekend lies ahead. Out West, record-breaking heat will continue across the Southwest, including Phoenix. Tucson will likely record its record-breaking 7th consecutive day with temperatures reaching 110° or above. Daily Records for June 18: Phoenix: 115°, 1989 and 2015 (Forecast: 115° to 119°) Tucson: 113°, 1989 (Forecast: 110° to 114°) *-Forecast range is 1 sigma below and above the forecast mean.

A historic early summer heatwave has toppled temperature records in many parts of the West. Through June 17, highlights include Phoenix’s earliest 118° temperature on record (last year set the mark for its latest such reading); Death Valley’s 128° temperature, which tied the June record and set a world record for hottest temperature during the second decade of June; Palm Springs’ all-time record-tying 123° temperature; Salt Lake City’s all-time record-tying 107° temperature; and Tucson’s record-tying six consecutive 110° temperatures (a record that will likely be broken on June 18). Anthropogenic climate change is contributing to such events through resonance events. It is encouraging that some of the major news outlets have made a direct connection between the historic heat and climate change. Some highlights: CNN: An unrelenting drought and record heat, both worsened by the changing climate, have pushed the water supply at Northern California's Lake Oroville to deplete rapidly. https://www.cnn.com/2021/06/17/us/california-drought-oroville-power/index.html The New York Times: Global warming, driven by the burning of fossil fuels, has been heating up and drying out the American West for years. Now the region is broiling under a combination of a drought that is the worst in two decades and a record-breaking heat wave. “The Southwest is getting hammered by climate change harder than almost any other part of the country, apart from perhaps coastal cities,” said Jonathan Overpeck, a climate scientist at the University of Michigan. “And as bad as it might seem today, this is about as good as it’s going to get if we don’t get global warming under control.” https://www.nytimes.com/2021/06/17/climate/wildfires-drought-climate-change-west-coast.html The Washington Post: Fueled by climate change, the first major heat wave of the summer has seized the western United States, toppling records and threatening lives. The event is unprecedented in its timing, intensity and scope, said Washington State University climate scientist Deepti Singh; never have such severe conditions been recorded over such a large area so early in the summer. https://www.washingtonpost.com/climate-environment/2021/06/17/record-heat-wave-west/ Such coverage is consistent with good journalism. Indeed, responsible journalism requires publication of facts linking the extreme heatwave to climate change given the overwhelming body of evidence now available within the scientific community.

A warming trend will develop starting tomorrow as some of the heat baking the Southwest begins to move into the region. The temperature could reach or exceed 90° in parts of the region during the weekend. Out West, an extreme heatwave continued in the Southwest, including Phoenix. High temperatures included: Blythe, CA: 119° (old record: 116°, 2015) Bullhead City, AZ: 120° (old record: 117°, 2008) Casper: 94° Death Valley, CA: 128° (old record: 122°, 1917) ***tied June record*** Denver: 100° (old record: 98°, 2012) ***3rd consecutive 100° day*** Flagstaff: 92° (tied record set in 1940) Las Vegas: 114° (old record: 113°, 1940) Needles: 120° (tied record set in 1917) Palm Springs: 123° (old record: 116°, 1961) ***new June record; tied all-time record*** Phoenix: 118° (old record: 114°, 1896 and 2015) Sacramento: 107° (old record: 103°, 1963) Tucson: 112° (old record: 109°, 1917, 1985, 1989, 2008, and 2015) At Phoenix, the temperature hit 118°. That is the earliest 116° or above temperature on record. The previous record was set on June 19, 2016 when the temperature also reached 118°. That record was tied in 2017. At Tucson, the temperature reached 110° or above for the sixth consecutive day. That tied June 24-29, 1994 for the longest streak on record. Records go back to September 1894. Today was also the sixth consecutive record high temperature at Tucson. The Tucson NWS office reported that the temperature reached 100° at Tucson at 8:14 am MST. That is the second earliest such reading, behind June 20, 2017 when the temperature reached 100° at 8:02 am. The extreme heat will continue into the weekend. The temperature could reach 115° on multiple days in Phoenix during this time. For reference, Phoenix's daily records for the June 18-19 period are posted below. Record high maximum temperatures: June 18: 115°, 1989 and 2015 June 19: 118°, 2016 and 2017 Record high minimum temperatures: June 18: 88°, 2008 June 19: 86°, 1958 and 1959 The ENSO Region 1+2 anomaly was 0.0°C and the Region 3.4 anomaly was 0.0°C for the week centered around June 9. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.48°C and the ENSO Region 3.4 anomaly has averaged -0.23°C. Neutral ENSO conditions will likely prevail into at least mid-summer. The SOI was +9.28 today. The preliminary Arctic Oscillation (AO) figure was +0.921 today. On June 15 the MJO was in Phase 2 at an amplitude of 1.344 (RMM). The June 14-adjusted amplitude was 1.286 (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 74% probability that New York City will have a warmer than normal June (1991-2020 normal). June will likely finish with a mean temperature near 73.8° (1.8° above normal).

Although the value of knowledge is realized more broadly than within the field in which the knowledge was developed once that knowledge is applied, that does not mean that such knowledge lacks intrinsic value. The potential value from understanding of the changing climate and its predominant cause would be unlocked from taking the appropriate steps to move toward net zero emissions. The value of the benefits would be substantial. In the fossil fuel-centered status quo, there are enormous adverse externalities (health effects, disasters from extreme events attributed to climate change, reduced productivity during heat events, agricultural losses from more frequent/expansive/intensive drought, fire damage, etc.). Those externalities are covered by society at large, rather than the major fossil fuel producers. That’s why they go unnoticed, but not unpaid. An IMF working paper estimated that the post-tax value of such externalities in the U.S. currently exceeds $640 billion per year (and $4.7 trillion per year globally). That’s about 3% of GDP. Realization of net zero emissions would eliminate that massive externality. That societal saving would represent a benefit of climate science understanding. https://www.imf.org/-/media/Files/Publications/WP/2019/WPIEA2019089.ashx That confirmation bias/other cognitive biases, motivated reasoning and an unethical disinformation campaign waged by climate change denial sources (barriers over which climate scientists have little influence) impede a timely human response, does not diminish the value of climate science. It only impedes realization of that value.

The preliminary low temperature at Phoenix was 91°. That would break the daily highest minimum temperature record of 88°, which was set in 1986 and tied in 2008. It would also be the earliest 91° minimum temperature on record. The existing record was set on June 22, 2017 when the minimum temperature was 91°.

Morning thoughts... Today will be mostly sunny and pleasant. Temperatures will likely reach the upper 70s and lower 80s in most places. Likely high temperatures around the region include: New York City (Central Park): 78° Newark: 83° Philadelphia: 79° Normals: New York City: 30-Year: 80.3°; 15-Year: 80.1° Newark: 30-Year: 82.5°; 15-Year: 82.5° Philadelphia: 30-Year: 83.8°; 15-Year: 84.0° A warming trend will begin tomorrow ahead of a very warm weekend. Out West, record-breaking heat will continue across the Southwest, including Phoenix. Phoenix will likely see its earliest 116° or above temperature on record today. Daily Records for June 17: Phoenix: 114°, 1896 and 2015 (Forecast: 115° to 119°) Tucson: 109°, 1917, 1985, 1989, 2008, and 2015 (Forecast: 110° to 114°) *-Forecast range is 1 sigma below and above the forecast mean.