donsutherland1

Morning thoughts… It will be variably cloudy and hot. Thunderstorms are likely as a cold front moves across the region. Some of the thunderstorms could be severe. High temperatures will reach the lower and middle 90s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 90° Newark: 96° Philadelphia: 93° Tomorrow and Wednesday will be cooler. Normals: New York City: 30-Year: 85.1°; 15-Year: 86.2° Newark: 30-Year: 86.9°; 15-Year: 88.3° Philadelphia: 30-Year: 87.8°; 15-Year: 88.8°

Under abundant sunshine, along with only some wispy high clouds, temperature records were approached, tied, or broken in many parts of the Northeast. High temperatures included: Albany: 97° (old record: 96°, 1941) Allentown: 95° (tied record set in 1999 and tied in 2016) Atlantic City: 99° Baltimore: 97° Boston: 100° (old record: 98°, 1933) Bridgeport: 94° Burlington: 91° Concord: 96° Halifax: 87° (old record: 85°, 1975) Harrisburg: 96° (tied record set in 1965 and tied in 1999 and 2001) Hartford: 96° (tied record set in 1987) Islip: 92° Manchester, NH: 98° (old record: 95°, 2001 New York City-JFK: 96° New York City-LGA: 98° (tied record set in 1999 and tied in 2010) New York City-NYC: 95° Newark: 102° (old record: 99°, 2010) Philadelphia: 99° (old record: 98°, 2011) Poughkeepsie: 96° Providence: 98° (old record: 94°, 1933 and 1987) Scranton: 97° (old record: 95°, 1933 and 2016) St. John's, NL: 87° (old record: 84°, 1952) Washington, DC: 94° Wilmington, DE: 95° With Newark recording a record 5 consecutive 100° high temperatures, it has had a mean high temperature of 92.2° over the past 30 days. The last time that occurred was during June 19-July 18, 2012 when the average temperature was also 92.2°. Tomorrow will be slightly cooler, but temperatures will still reach the lower 90s across much of the region. Afterward, temperatures will become several degrees cooler through midweek. During June 16-20, the MJO has been in Phase 1 at an amplitude of 1.500 or above. Of the six cases that saw such an outcome during June 15-25 (1988, 2003, 2010, 2012, 2017 and 2020), four had a warmer than normal July, one was somewhat cooler than normal and one was cooler than normal. The latest guidance all indicates that July will wind up solidly among the warmer than normal cases. The ECMWF seasonal forecast indicates that the summer will be warmer than normal throughout the region and across much of North America. Based on how the pattern has been evolving during the spring transition to summer, it is more likely than not that the warmest anomalies of the summer will likely occur in July and August with June being the coolest of the three months in the Northeast. The latest ECMWF monthly forecast indicates that July will be warmer than June relative to normal and that August will be the warmest summer month relative to normal. In addition, in the 6 past cases when the June AO averaged +0.750 or above (1950-2021), 50% of the following July cases were warmer than normal. 67% of the following August and September cases featured above normal temperatures. The ENSO Region 1+2 anomaly was -1.2°C and the Region 3.4 anomaly was -0.6°C for the week centered around July 13. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.40°C and the ENSO Region 3.4 anomaly has averaged -0.60°C. La Niña conditions will likely persist through the summer. The SOI was +2.15. The preliminary Arctic Oscillation (AO) was -1.144 today. On July 22 the MJO was in Phase 1 at an amplitude of 1.504 (RMM). The July 21-adjusted amplitude was 1.148 (RMM). Based on sensitivity analysis applied to the latest guidance, there is an implied 98% probability that New York City will have a warmer than normal July (1991-2020 normal). July will likely finish with a mean temperature near 80.0° (2.5° above normal).

Morning thoughts… It will be mostly sunny and very hot with near record and record heat. There could be afternoon or evening thunderstorms. High temperatures will reach 95°-100° most of the region. Likely high temperatures around the region include: New York City (Central Park): 96° Newark: 102° Philadelphia: 100° Tomorrow will be somewhat cooler. Normals: New York City: 30-Year: 85,2°; 15-Year: 86.3° Newark: 30-Year: 86.9°; 15-Year: 88.3° Philadelphia: 30-Year: 87.8°; 15-Year: 88.9° Select daily records for July 24: Allentown: 95°, 1999 and 2016 Baltimore: 101°, 2010 Bridgeport: 95°, 2010 Hartford: 96°, 1987 Islip: 96°, 2010 New York City-JFK: 97°, 2010 New York City-LGA: 98°, 1999 and 2010 New York City-NYC: 97°, 1999 and 2010 Newark: 99°, 2010 Philadelphia: 98°, 2011 Poughkeepsie: 100°, 1933 Washington, DC: 101°, 2010 White Plains: 95°, 1952

A hot day that saw temperatures rise into the middle and upper 90s in much of the region has concluded. Tomorrow has the potential to be a few degrees warmer. Tomorrow will feature sunshine with near record and record heat. Highs will reach 95°-100° with higher figures in the lower 100s across much of the region. Select daily records for July 24: Allentown: 95°, 1999 and 2016 Baltimore: 101°, 2010 Bridgeport: 95°, 2010 Hartford: 96°, 1987 Islip: 96°, 2010 New York City-JFK: 97°, 2010 New York City-LGA: 98°, 1999 and 2010 New York City-NYC: 97°, 1999 and 2010 Newark: 99°, 2010 Philadelphia: 98°, 2011 Poughkeepsie: 100°, 1933 Washington, DC: 101°, 2010 White Plains: 95°, 1952 Monday will be slightly cooler, but temperatures will still reach the lower 90s across much of the region. Afterward, temperatures will become several degrees cooler through midweek. During June 16-20, the MJO has been in Phase 1 at an amplitude of 1.500 or above. Of the six cases that saw such an outcome during June 15-25 (1988, 2003, 2010, 2012, 2017 and 2020), four had a warmer than normal July, one was somewhat cooler than normal and one was cooler than normal. The latest guidance all indicates that July will wind up solidly among the warmer than normal cases. The ECMWF seasonal forecast indicates that the summer will be warmer than normal throughout the region and across much of North America. Based on how the pattern has been evolving during the spring transition to summer, it is more likely than not that the warmest anomalies of the summer will likely occur in July and August with June being the coolest of the three months in the Northeast. The latest ECMWF monthly forecast indicates that July will be warmer than June relative to normal and that August will be the warmest summer month relative to normal. In addition, in the 6 past cases when the June AO averaged +0.750 or above (1950-2021), 50% of the following July cases were warmer than normal. 67% of the following August and September cases featured above normal temperatures. The ENSO Region 1+2 anomaly was -1.2°C and the Region 3.4 anomaly was -0.6°C for the week centered around July 13. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.40°C and the ENSO Region 3.4 anomaly has averaged -0.60°C. La Niña conditions will likely persist through the summer. The SOI was +1.66. The preliminary Arctic Oscillation (AO) was -1.122 today. On July 21 the MJO was in Phase 8 at an amplitude of 1.148 (RMM). The July 20-adjusted amplitude was 0.689 (RMM). Based on sensitivity analysis applied to the latest guidance, there is an implied 97% probability that New York City will have a warmer than normal July (1991-2020 normal). July will likely finish with a mean temperature near 80.0° (2.5° above normal).

Morning thoughts… It will be mostly sunny and very hot. Thee could be afternoon or evening thunderstorms. High temperatures will reach 95°-100° most of the region. Likely high temperatures around the region include: New York City (Central Park): 96° Newark: 101° Philadelphia: 99° Tomorrow will be another very hot day. Normals: New York City: 30-Year: 85,2°; 15-Year: 86.3° Newark: 30-Year: 87.0°; 15-Year: 88.4° Philadelphia: 30-Year: 87.9°; 15-Year: 88.0°

The ongoing heatwave has now qualified as an Extreme Heat Event (EHE) in Newark. At least 3 days have seen the maximum temperature exceed the 97.5th percentile (98° or above), the average high during that period exceeded the 97.5th percentile, and all high temperatures exceeded the 81st percentile (90° or above) in June-August high temperatures for the 1971-2000 base period (Clarke, et al.,2014).

The hottest temperatures of the year are likely this weekend. Widespread high temperatures of 95°-100° with higher figures in the lower 100s are likely. Monday will be slightly cooler, but temperatures will still reach the lower 90s across much of the region. Afterward, temperatures will become several degrees cooler through midweek. During June 16-20, the MJO has been in Phase 1 at an amplitude of 1.500 or above. Of the six cases that saw such an outcome during June 15-25 (1988, 2003, 2010, 2012, 2017 and 2020), four had a warmer than normal July, one was somewhat cooler than normal and one was cooler than normal. The latest guidance all indicates that July will wind up solidly among the warmer than normal cases. The ECMWF seasonal forecast indicates that the summer will be warmer than normal throughout the region and across much of North America. Based on how the pattern has been evolving during the spring transition to summer, it is more likely than not that the warmest anomalies of the summer will likely occur in July and August with June being the coolest of the three months in the Northeast. The latest ECMWF monthly forecast indicates that July will be warmer than June relative to normal and that August will be the warmest summer month relative to normal. In addition, in the 6 past cases when the June AO averaged +0.750 or above (1950-2021), 50% of the following July cases were warmer than normal. 67% of the following August and September cases featured above normal temperatures. The ENSO Region 1+2 anomaly was -1.2°C and the Region 3.4 anomaly was -0.6°C for the week centered around July 13. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.40°C and the ENSO Region 3.4 anomaly has averaged -0.60°C. La Niña conditions will likely persist through the summer. The SOI was -2.89. The preliminary Arctic Oscillation (AO) was -1.260 today. On July 20 the MJO was in Phase 8 at an amplitude of 0.690 (RMM). The July 19-adjusted amplitude was 0.128 (RMM). Based on sensitivity analysis applied to the latest guidance, there is an implied 95% probability that New York City will have a warmer than normal July (1991-2020 normal). July will likely finish with a mean temperature near 80.0° (2.5° above normal).

Phoenix recorded just its 7th 95-degree low on record this morning. Records go back to August 1895.

From Teterboro:

A westerly wind is a downsloping wind. It leads to heating in such cities as Newark and Hartford, which often wind up much warmer than other localities that are less impacted by the downsloping winds. A simple explanation of the link between downsloping winds and rising temperatures from the Binghamton office of the National Weather Service is: As a parcel of air rises, there is less and less air above it so the air parcel expands due to the decreasing surrounding air pressure. Likewise, as an air parcel descends there is more and more air above it so the parcel becomes compressed. The Ideal Gas Law (PV=nRT) tells us that if the pressure of an air parcel changes but all other aspects of the parcel remain the same, there must be a corresponding change in temperature to keep the equation balanced. Thus, rising air expands and cools while descending air compresses and warms. https://www.weather.gov/bgm/WeatherInActionDownSlopeWinds

Morning thoughts… It will be mostly sunny and hot. Thee could be afternoon or evening thunderstorms. High temperatures will reach the middle and upper 90s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 92° Newark: 99° Philadelphia: 98° Hot weather will continue through at least the weekend. Normals: New York City: 30-Year: 85,2°; 15-Year: 86.4° Newark: 30-Year: 87.1°; 15-Year: 88.5° Philadelphia: 30-Year: 88.0°; 15-Year: 89.1°

The wind was off the Potomac River for much of the day.

The longest heatwave so far this summer is now underway. Much of the region saw temperatures rise into the middle 90s with some hotter spots. Highs included: Albany: 96° Baltimore: 95° Boston: 92° Bridgeport: 93° Burlington: 93° Hartford: 97° Islip: 95° New York City-JFK: 95° New York City-LGA: 97° New York City-NYC: 95° Newark: 100° Philadelphia: 96° Washington, DC: 91° The heat will continue through at least the weekend. The hottest temperatures will likely be west of New York City in adjacent New Jersey where temperatures could peak in the upper 90s and likely reach or exceed 100° on the hottest days. During June 16-20, the MJO has been in Phase 1 at an amplitude of 1.500 or above. Of the six cases that saw such an outcome during June 15-25 (1988, 2003, 2010, 2012, 2017 and 2020), four had a warmer than normal July, one was somewhat cooler than normal and one was cooler than normal. The latest guidance all indicates that July will wind up solidly among the warmer than normal cases. The ECMWF seasonal forecast indicates that the summer will be warmer than normal throughout the region and across much of North America. Based on how the pattern has been evolving during the spring transition to summer, it is more likely than not that the warmest anomalies of the summer will likely occur in July and August with June being the coolest of the three months in the Northeast. The latest ECMWF monthly forecast indicates that July will be warmer than June relative to normal and that August will be the warmest summer month relative to normal. In addition, in the 6 past cases when the June AO averaged +0.750 or above (1950-2021), 50% of the following July cases were warmer than normal. 67% of the following August and September cases featured above normal temperatures. The ENSO Region 1+2 anomaly was -1.2°C and the Region 3.4 anomaly was -0.6°C for the week centered around July 13. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.40°C and the ENSO Region 3.4 anomaly has averaged -0.60°C. La Niña conditions will likely persist through the summer. The SOI was +2.22. The preliminary Arctic Oscillation (AO) was -1.109 today. On July 18 the MJO was in Phase 5 at an amplitude of 0.337 (RMM). The July 17-adjusted amplitude was 0.735 (RMM). Based on sensitivity analysis applied to the latest guidance, there is an implied 90% probability that New York City will have a warmer than normal July (1991-2020 normal). July will likely finish with a mean temperature near 79.8° (2.3° above normal).

LaGuardia Airport had a low temperature of 80° this morning. The number of such minimum temperatures has increased dramatically in recent years, both annually and during July. During 1961-1990, there were 10 low temperatures of 80° or above. During 1991-2020, there were 38 such temperatures. Low temperatures below 60° have become rare. During 1961-1990 there were 16 such days. During 1991-2020, there were 4. Overall, the average July low temperature at LaGuardia Airport has increased from 68.9° during 1961-1990 to 71.4° during 1991-2020. The July distribution of low temperatures is below:

Yesterday, Phoenix had a low temperature of 94. That tied the daily record from 2010 and was just the 12th 94 or above low temperature in July (16th overall). Such outcomes have increased in Phoenix's warmer climate (Mean July lows: 1961-1990: 81.0F; 1991-2020: 84.2F). The distribution of Phoenix’s July low temperatures is below (1961-1990 vs. 1991-2020).

Morning thoughts… It will be mostly sunny and hot. High temperatures will reach the lower and middle 90s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 93° Newark: 100° Philadelphia: 97° Hot weather will continue through at least the weekend. Normals: New York City: 30-Year: 85.3°; 15-Year: 86.4° Newark: 30-Year: 87.2°; 15-Year: 88.5° Philadelphia: 30-Year: 88.0°; 15-Year: 89.1°

The longest heatwave so far this summer is developing. The hottest temperatures will likely be west of New York City in adjacent New Jersey where temperatures could peak in the upper 90s and perhaps reach or exceed 100° at the height of the heatwave. During June 16-20, the MJO has been in Phase 1 at an amplitude of 1.500 or above. Of the six cases that saw such an outcome during June 15-25 (1988, 2003, 2010, 2012, 2017 and 2020), four had a warmer than normal July, one was somewhat cooler than normal and one was cooler than normal. The latest guidance all indicates that July will wind up solidly among the warmer than normal cases. The ECMWF seasonal forecast indicates that the summer will be warmer than normal throughout the region and across much of North America. Based on how the pattern has been evolving during the spring transition to summer, it is more likely than not that the warmest anomalies of the summer will likely occur in July and August with June being the coolest of the three months in the Northeast. The latest ECMWF monthly forecast indicates that July will be warmer than June relative to normal and that August will be the warmest summer month relative to normal. In addition, in the 6 past cases when the June AO averaged +0.750 or above (1950-2021), 50% of the following July cases were warmer than normal. 67% of the following August and September cases featured above normal temperatures. The ENSO Region 1+2 anomaly was -1.2°C and the Region 3.4 anomaly was -0.6°C for the week centered around July 13. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.40°C and the ENSO Region 3.4 anomaly has averaged -0.60°C. La Niña conditions will likely persist through the summer. The SOI was -0.43. The SOI was negative for the third consecutive day. The last time that happened was February 13-16, 2022 when the SOI was negative for four consecutive days. The preliminary Arctic Oscillation (AO) was -0.621 today. On July 17 the MJO was in Phase 4 at an amplitude of 0.734 (RMM). The July 16-adjusted amplitude was 0.960 (RMM). Based on sensitivity analysis applied to the latest guidance, there is an implied 90% probability that New York City will have a warmer than normal July (1991-2020 normal). July will likely finish with a mean temperature near 79.8° (2.3° above normal).

San Antonio reached 100 degrees for the 40th time this year. The old record through July 19th was 27 days in 2009. Only 2009, 2011 and 2013 had 40 or more days for a whole year. The increasing frequency of 100-degree days is the result of warming summers.

Also, this attribution study from the July 2019 heatwave in Europe is very likely representative. A key finding: It is noteworthy that every heatwave analysed so far in Europe in recent years (2003, 2010, 2015, 2017, 2018, June 2019 and this study) was found to be made much more likely and more intense due to human-induced climate change. How much more depends very strongly on the event definition: location, season, intensity and durations. The July 2019 heatwave was so extreme over continental Western Europe that the observed magnitudes would have been extremely unlikely without climate change. https://www.worldweatherattribution.org/wp-content/uploads/July2019heatwave.pdf

A historic day:

39.1C at Charlwood Surrey. https://twitter.com/metoffice/status/1549345259016142848?s=20&t=G3wOdvxQETuxLdmQiwP-2A

Morning thoughts… It will be mostly sunny and hot. High temperatures will 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: 94° Hot weather will continue through at least the weekend. 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: 89.1°

With 1.85” of rain through 7:08 on EDT, Central Park has surpassed its daily record rainfall of 1.76” from 2012.

Showers and thunderstorms, some of which could be heavy, will continue through at least the first half of tonight. Additional flooding is possible in parts of New Jersey and southeastern New York State. Afterward, another spell of heat will develop. The potential exists for the longest heatwave so far this summer. The hottest temperatures will likely be west of New York City in adjacent New Jersey where temperatures could peak in the upper 90s and perhaps reach 100° at the height of the heatwave. The temperature reached 99° at London's Heathrow Airport today and 101° at Standon Downham. Jersey reached 100° for the first time on record. The national UK record will likely be broken tomorrow. The possibility exists that the UK could see its first 40°C (104°F) temperature on record. In France, Biscarosse reached a scorching 109°. Overall, 25 locations set new all-time high temperature records. During June 16-20, the MJO has been in Phase 1 at an amplitude of 1.500 or above. Of the six cases that saw such an outcome during June 15-25 (1988, 2003, 2010, 2012, 2017 and 2020), four had a warmer than normal July, one was somewhat cooler than normal and one was cooler than normal. The latest guidance all indicates that July will wind up among the warmer than normal cases. The ECMWF seasonal forecast indicates that the summer will be warmer than normal throughout the region and across much of North America. Based on how the pattern has been evolving during the spring transition to summer, it is more likely than not that the warmest anomalies of the summer will likely occur in July and August with June being the coolest of the three months in the Northeast. The latest ECMWF monthly forecast indicates that July will be warmer than June relative to normal and that August will be the warmest summer month relative to normal. In addition, in the 6 past cases when the June AO averaged +0.750 or above (1950-2021), 50% of the following July cases were warmer than normal. 67% of the following August and September cases featured above normal temperatures. The ENSO Region 1+2 anomaly was -1.2°C and the Region 3.4 anomaly was -0.6°C for the week centered around July 13. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.40°C and the ENSO Region 3.4 anomaly has averaged -0.60°C. La Niña conditions will likely persist through the summer. The SOI was -6.40. The preliminary Arctic Oscillation (AO) was -0.035 today. On July 16 the MJO was in Phase 4 at an amplitude of 0.962 (RMM). The July 15-adjusted amplitude was 0.987 (RMM). 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 July (1991-2020 normal). July will likely finish with a mean temperature near 79.6° (2.1° above normal).

The air base at Brize Norton also suffered infrastructure damage from the heat.