donsutherland1

Today was the most brutal day during the ongoing epic heatwave in the West. A new U.S. national temperature record for March was set at four locations.

The Climate Extremes Index includes cold. However, for the Southwest, extreme cold has disappeared in recent years. Here's the CEI's temperature charts:

The temperature will rise to the middle and upper 50s tomorrow and lower to perhaps middle 60s during on Sunday. A few showers are possible on tomorrow. A somewhat cooler air mass will likely arrive early next week. The major weather story this week is the ongoing super March heatwave in much of the western U.S. March monthly records are being set in numerous cities. The ENSO Region 1+2 anomaly was +1.5°C and the Region 3.4 anomaly was 0.0°C for the week centered around March 11. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.98°C and the ENSO Region 3.4 anomaly has averaged -0.15°C. Neutral ENSO conditions will continue through at least mid-spring. The SOI was -3.83 today. The preliminary Arctic Oscillation (AO) was +2.345 today. 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 March (1991-2020 normal). March will likely finish with a mean temperature near 44.6° (1.8° above normal). Supplemental Information: The projected mean would be 2.1° above the 1981-2010 normal monthly value.

Although the flash analysis isn't peer reviewed, it is derived from a peer-reviewed methodology, which provides credibility. These studies provide value, as they provide an alternative to pure statistical research. The corroboration between the modeling and statistics enhances the quality of their findings. Further, studies concerning prior extreme heat outbreaks in the Southwest have all found a strong link to climate change. As for March 2026, March 2026 is poised to become Phoenix's first March to break outside the 99% confidence interval based on 30-year climate data.

World Weather Attribution's flash analysis of the unprecedented March heat in western North America. Excerpt: Observation-based data products show a strong increase in the likelihood and intensity of heat waves in the region, suggesting that such events have become about 4°C warmer as a best estimate, and that events as warm as in March 2026 would have been virtually impossible without human-induced climate change. Climate models strongly underestimate this observed trend but still show a significant increase in extreme heat. We combine models and observations, giving equal weight to both lines of evidence, and find an estimated increase in intensity of 2.6°C for such events, with an increase in likelihood of a factor of about 800. This means that without climate change it would have been virtually impossible for the event to occur.

Some monthly records through today: Note: The final high in Albuquerque was 88°, not the initially reported 90°. The Airport's sensor had an issue. The updated graph for Phoenix is below:

That statement about a near zero impact is wrong. The impact is smaller but not near zero. Water vapor saturation does not mean that additional CO2 won't have an impact. Water vapor has a maximum impact in the lower atmosphere. The upper atmosphere is drier. Increased CO2 reduces outgoing longwave radiation, leading to additional warming.

The temperature will return to the middle 40s tomorrow afternoon. Readings will then return to the 50s for Friday and then the upper 50s and lower 60s during the weekend. A few showers are possible on Saturday. A somewhat cooler air mass will likely arrive early next week. The major weather story this week is the super March heatwave that is under way in much of the western U.S. March monthly records are being set in numerous cities. Today, Albuquerque, Flagstaff, Palm Springs, Phoenix, and Tucson are among the cities setting March monthly records. Additional records are likely in coming days. The ENSO Region 1+2 anomaly was +1.5°C and the Region 3.4 anomaly was 0.0°C for the week centered around March 11. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.98°C and the ENSO Region 3.4 anomaly has averaged -0.15°C. Neutral ENSO conditions will continue through at least mid-spring. The SOI was +0.43 today. The preliminary Arctic Oscillation (AO) was +2.006 today. 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 March (1991-2020 normal). March will likely finish with a mean temperature near 44.6° (1.8° above normal). Supplemental Information: The projected mean would be 2.1° above the 1981-2010 normal monthly value.

Below are the March 1-18 high temperatures vs. the daily records for Phoenix:

It will begin to turn milder tomorrow. The temperature will return to the middle 40s tomorrow afternoon. Readings will then return mainly to the 50s for Friday through the weekend. The mercury could reach 60° on Saturday. The major weather story this week is the super March heatwave that is under way in much of the western U.S. March monthly records are being set in numerous cities. Today, Flagstaff, Palm Springs, and Phoenix are among the cities setting March monthly records. Additional records are likely in coming days. The ENSO Region 1+2 anomaly was +1.5°C and the Region 3.4 anomaly was 0.0°C for the week centered around March 11. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.98°C and the ENSO Region 3.4 anomaly has averaged -0.15°C. Neutral ENSO conditions will continue through at least mid-spring. The SOI was +3.73 today. The preliminary Arctic Oscillation (AO) was +0.539 today. 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 March (1991-2020 normal). March will likely finish with a mean temperature near 44.7° (1.9° above normal). Supplemental Information: The projected mean would be 2.2° above the 1981-2010 normal monthly value.

The long-advertised historic March heatwave is now gathering force in the Southwest. Already, monthly high temperature records have fallen in Burbank, Camarillo, and Thermal. Monthly marks were tied in Flagstaff and San Francisco. Downtown Los Angeles missed its longstanding monthly record from 1879 by 1°. Although Palm Springs missed its monthly record by 1° yesterday, it demolished its monthly warmest minimum temperature record by 5° with a low of 75° (a level not seen previously until April 21st). Following the conclusion of a winter that was the warmest on record for many parts of the region, the signature for a possible heat event appeared far in advance. ECMWF Weeklies: March 1: The guidance remained persistence and moved toward an extreme event as the lead time shortened. ECMWF Weeklies: March 7: The final ECMWF weekly forecast from March 15 showed a record-breaking event was imminent. ECMWF Weeklies: March 15: Despite the attention high-profile urban areas receive, the entire region has been warming. Southwest (1980-2025): Warming can produce a non-linear increase in the frequency and severity of heat events, including outside of summer. The March 2012 and September-October 2024 heat events are examples. Climate Central has estimated that climate change has made the forecast event for the Southwest/West at least 5 times more likely in much of those regions. One can expect an avalanche of monthly records over the coming days. Some records could reach or exceed April monthly marks.

Colder air has returned to the region. After a low in the upper 20s tomorrow morning, New York City will see a high near or just below 40°. Thursday will see the temperature return to the middle 40s. Readings will then return to the 50s for Friday through the weekend. The major weather story this week will be the super March heatwave that is now developing in much of the western U.S. March monthly records are likely to be smashed in numerous cities, including Albuquerque, Flagstaff, Fresno, Las Vegas, Palm Springs, Phoenix, Reno, Salt Lake City, and Yuma. Already, Camarillo, CA reached a March record 96° today. The ENSO Region 1+2 anomaly was +1.5°C and the Region 3.4 anomaly was 0.0°C for the week centered around March 11. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.98°C and the ENSO Region 3.4 anomaly has averaged -0.15°C. Neutral ENSO conditions will continue through at least mid-spring. The SOI was +1.87 today. The preliminary Arctic Oscillation (AO) was +0.492 today. Based on sensitivity analysis applied to the latest guidance, there is an implied 84% probability that New York City will have a warmer than normal March (1991-2020 normal). March will likely finish with a mean temperature near 45.1° (2.3° above normal). Supplemental Information: The projected mean would be 2.6° above the 1981-2010 normal monthly value.

The unprecedented March heatwave is starting to build in the Phoenix area. As a result, March 2026 will very likely surpass the existing monthly mark by the largest margin on record for Phoenix. Through March 16th, Phoenix has a mean temperature of 73.3°. The prior March 1-16 record was 72.3° in 1972. So far, 25% of days have either tied or set daily records. So, even without the upcoming historic heatwave, March was running exceptionally warm.

This is very sad news. He was a fantastic member. May he rest in peace.

I am very sorry to learn this sad news. He was a great member and good person.