According to actual measured data from around the world the three hottest years ever recorded were, starting with the hottest, 2024, 2023 and 2025. It’s true, the last three years have been the hottest, at least the hottest since human beings developed the instrumentation to accurately measure temperature. In fact the last ten years have been the hottest ten years ever recorded, undeniable evidence that Climate Change is real and accelerating.
So far it looks like 2026 could surpass them all. For one thing the amount of CO2 and other greenhouse gasses in the atmosphere continues to grow, reaching a level of 428 Parts per Million (PPM) in late 2025, the highest amount ever measured. As the year began it was winter in the northern hemisphere, which gave some respite from the heat, but in the southern hemisphere it was summer and 2026 was already setting heat records.
In Australia during January the southeast of that country saw a heat dome develop that led to numerous days of temperature surpassing 45ºC in dozens of cities including Melbourne the state capital of Victoria. The all time state record for Victoria was smashed on the 27th of January when the small towns of Hopetoun and Walpeup both saw temperatures of 48.9ºC. On the same day in the state of New South Wales a temperature of 49.7ºC was recorded in the village of Pooncarie. In all over 50 weather stations across south Australia saw their all time high temperature reading.
With those extreme temperatures came wildfires that raged across the southeast destroying both property and wildlife. In the state of Victoria over 1.1 million acres of land were burned. Even sporting events were not exempt from the heat with sky resorts in the Australian Alps seeing temperatures over 30ºC and the Australian Open tennis tournament having to operate under extreme heat protocols. It’s thought that the January heat wave cost the tennis tournament as much as $1million in lost ticket sales.
Meanwhile in South American there was another heat wave in the nations of Chile and Argentina in South America with temperatures rising to over 38ºC. Just as in Australia, the record temperatures sparked wildfires, those in Chile consumed 21,000 acres and caused the death of 8 people. Argentina meanwhile also had numerous wildfires in Patagonia, which is fortunately a much less populated area.
Summer in the southern hemisphere is supposed to mean winter in the northern hemisphere, and at least cooler temperatures. Here in my home of Philadelphia it was an unusually cold winter. Notice my wording there, unusual, not extreme or unprecedented, just unusual. It was the coldest, and snowiest January and February in the last five years but no record lows were set nor were there any huge blizzards that paralyzed the city for days. The same was true of much of the US east of the Mississippi, an unusually cold winter.
Out west however it was a different story as nine states recorded their hottest ever winter, along with four states recording their second warmest. This excessive heat out west was actually part of the reason that the eastern US was unusually cold, as a huge high pressure system, another heat dome, established itself over the western third of the country creating a clockwise flow of air around it that brought cold Canadian air south into the eastern US. The high temperatures and high pressure out west combined to severely limit the amount of snow that fell on the Rockies and Sierra Nevada’s, in fact the west as a whole saw little precipitation throughout the entire winter.
Then in March, as winter turned to spring the high pressure in the west grew in strength and the entire country saw record-breaking high temperatures. Here in Philly we had three days setting records on the 10th, 11th and 31st of March. Salt Lake City beat us however with six record high temperatures while Las Vegas endured five straight days of record highs. In fact the all time high temperature for the entire U.S. in the month of March was set near Martinez Lake in Arizona with a measurement of 43.3ºC. Across the entire country 8,201 daily high temperature records were set in March along with 2,027 monthly records!
The winner however had to be Phoenix, Arizona, which saw 14 all time daily high temperature records set. Think about that, almost every other day in Phoenix during the month of March set a record for all-time high temperature for that day. Prior to this year the highest temperature ever recorded in Phoenix in March was a 37.8ºC (100ºF) measured back in 1988. This year Phoenix endured nine days that hot or hotter.
In April the temperature in the west moderated somewhat while the temperatures in the east increased. Philadelphia saw its fourth warmest April while cities in the southeast were even hotter. In addition to the heat many of the states east of the Mississippi saw very little rain during March and April, joining the west in a nation wide drought. Reservoirs in California are at historic lows ever as the snow pack in the Sierras and Rockies is almost non-existent. The lack of water out west has already led to major wildfires but it’s the wildfires in Georgia and Florida that are making the headlines. With almost the entire country in a drought of some extent this summer’s wildfires could be unprecedented.
The coming of May didn’t bring much change, except the very hottest temperatures moved to Europe. Oh, the US was still hot, with daily records being set almost every day, but on the 25th of May Kew Gardens in London measured a temperature of 34.8ºC the hottest May temperature ever recorded in the entire United Kingdom. The next day Ireland set its all time heat record for May with a 29.7ºC measurement. Meanwhile a heat wave in France caused the death of at least nine people. According to the French weather service a heat dome had set up over Western Europe, so our planet is now in a condition where there is a heat dome at least somewhere all the time!
I’ll end this litany of disasters with one more grim thought, the signs are growing that another El Ninó is growing in the Pacific and right now it is forecast to be a very strong one, perhaps the strongest in over a century. Could this be the proverbial straw that breaks the Camel’s back? If this year is significantly hotter than 2024, currently the hottest ever recorded, the consequences will be devastating across the entire planet. We won’t have to wait long to see!