Phoenix Experiences Its Hottest Summer on Record for the Third Time in Five Years

[donsutherland1]

In what has become a seemingly regular occurrence beginning in 2020, Phoenix has experienced its hottest summer on record. Since 2020, Phoenix has eclipsed the summer mark in 2020, 2023, and again this year. A major theme, as was the case in 2020 and 2023 when the heat set in, was its persistence.

Summer 2024 got off to a blazing start with its hottest June, by far, on record. The sizzling June was followed by Phoenix’s second hottest July and second hottest month on record. July featured an 11-day extreme heat event (Clarke et al., 2014 methodology) during which the temperature reached or exceed 115° on six days. That was the second longest such event on record. Summer concluded with the third hottest August on record.

On account of the historic heat, Phoenix saw its longest stretches of 80° or above lows, 100° or above highs, and 105° or above highs:

• 80° or above lows: 74 days, June 5-August 17; old record: 51 days, July 1-August 20, 2023
• 100° or above highs: 97 days (as of August 31 and ongoing); old record: 76 days, June 10-August 24, 1993
• 105° or above highs: 63 days, June 5-August 6; old record: 56 days, June 24-August 18, 2023

Anthropogenic climate change amplified by the urban heat island effect is driving a warming of Arizona’s and Phoenix's summers. Data from a joint May 2024 report published by Climate Central, Red Cross Red Crescent Climate Centre and World Weather Attribution revealed that the influence of climate change has resulted in a 231.1% increase in Arizona’s days with temperatures above the 90^th percentile (1991-2020 baseline) over the figure expected without the influence of climate change.

The warming has accelerated in recent decades. Between 1950 and 2023, summers have warmed by 0.6° per decade in Phoenix. Since 1980, summers have warmed by 0.9° per decade. As a result, Phoenix has set summer records in 2020, 2023, and now 2024. As a result, the annual number of days on which the high temperature has exceeded the 90^th percentile for summer maximum readings (1991-2020 baseline) has increased from 6.5 days during 1961-1990 to 9.99 days during 1991-2020. The most recent 30-year moving average (1995-2024) is 12.7 such days per year (through August 31, 2024).

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Updates:

Phoenix records 100th 80° low temperature of the year

 

 

 

 

[donsutherland1]

Phoenix has now reached a record 100 consecutive 100-degree days.

[Typhoon Tip]

put a phys.org link over in Global Average Temperature 2024 

add s. korea to the list

[donsutherland1]

On September 5, Phoenix recorded a September record-tying 116° high temperature. A day later, Phoenix followed up with a new September monthly record high minimum temperature of 93°, which broke the old record by 2°. In California, Palm Springs recorded a low temperature of 95°, beating the September monthly mark by 3°. That was also tied for the second highest low temperature on record.

According to Climate Central's Climate Shift Index, this warmth was made at least 5 times more likely due to climate change.

[donsutherland1]

Yesterday, Phoenix recorded its 100th 80° low of the year, further extending its record. The combination of Urban Heat Island (UHI) Effect and ongoing anthropogenic warming has led to a dramatic explosion of the frequency of such hot nights.

[Typhoon Tip]

7 hours ago, donsutherland1 said:

Yesterday, Phoenix recorded its 100th 80° low of the year, further extending its record. The combination of Urban Heat Island (UHI) Effect and ongoing anthropogenic warming has led to a dramatic explosion of the frequency of such hot nights.

It’s mostly climate change…

I’ve never bought it that the urban he Island is a big enough factor in this thing because frankly, the urban heat is has been there since the middle of last century. So it’s on both sides of the trendline, and therefore should be equitable and eliminated as a common factor