donsutherland1

Here's where I think the issue lies. The graph is based on where the collapsing rock/glacier hit the valley (around 4,300 meters above sea level). The bedrock, glacier was about 5,200 meters. So, the graph is correct in that the region has been warming, but it is not the mean temperature of the actual glacier. Nevertheless, preceding the collapse, temperatures had reached 90° or above in Kathmandu. At standard lapse rates, that would suggest readings in the middle 40s at the altitude of the glacier. During the June 1-August 25 period, Kathmandu had 77 days with highs of 80° or above. At standard lapse rates, that would amount to highs of 35° or above at 5,200 meters. So, at least using the standard lapse rates and Kathmandu's data, most of the summer days saw at least some melting where the collapse took place.

It is, but both sites are in different Himalayan subregions with different topography and wind exposure.

The Everest base camp is about 160 km from the site of the bedrock/glacial collapse that occurred last month.

Florac, France, where September records go back to 1861, has recorded its three hottest September temperatures on record during the current heatwave. September 4, 1966 saw its first 30C (86F) or above September temperature on record.

A cool Labor Day weekend has commenced. Temperatures will generally peak in the middle and upper 70s. Readings in New York City could fall into the lower 60s with widespread 50s outside the City. The cool weather will likely continue into the middle of next week. By midweek, readings could return to the lower 80s. Another push of cooler air could arrive by Friday or Saturday. The ENSO Region 1+2 anomaly was +4.2°C and the Region 3.4 anomaly was +2.6°C for the week centered around August 26. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +3.93°C and the ENSO Region 3.4 anomaly has averaged +2.50°C. The ongoing strong El Niño, which has reached super El Niño threshold, will continue to strengthen through the summer. The SOI was -16.70 today. The preliminary Arctic Oscillation (AO) was +0.627 today.

A few areas could see an evening shower. Most of the region will remain dry. Cooler air will move in overnight. A cooler air mass will cover the region for the Labor Day weekend. In its wake, temperatures will generally peak in the middle and upper 70s. Readings in New York City could fall into the lower 60s with widespread 50s outside the City. The cool weather will likely continue through at least the middle of next week. The ENSO Region 1+2 anomaly was +4.2°C and the Region 3.4 anomaly was +2.6°C for the week centered around August 26. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +3.93°C and the ENSO Region 3.4 anomaly has averaged +2.50°C. The ongoing strong El Niño, which has reached super El Niño threshold, will continue to strengthen through the summer. The SOI was -7.78 today. The preliminary Arctic Oscillation (AO) was +0.293 today.

Highest daily values for each month and highest monthly and seasonal averages on ERA-5:

In advance, have a very happy birthday.

Here’s a reasonable substitute: https://www.pyreweather.org I hope the shortsighted decision to stop updating the PSL site will be reversed in the future.

The idea that the bedrock collapsed leading to the glacial collapse and subsequent debris flow has gained increasing support. However, one can't automatically suggest that because the bedrock collapsed, climate change wasn't involved. The literature links a warming climate to destabilization of high mountain terrain. One recent study noted: The study found that rising temperatures are destabilizing high mountain terrain in India’s Kinnaur district and creating conditions that could trigger chains of disasters, including avalanches or landslides that spill into glacier lakes and produce destructive flooding downstream. A quick assessment by University of Colorado researchers also linked climate change observing: Satellite and drone images suggest that softening permafrost, or perennially frozen rock, ice and soil, on Langtang Lirung peak likely caused a massive bedrock failure and glacier collapse. An estimated 50 million metric tons of ice, rock and water—roughly 13 billion gallons, or about three times the capacity of Boulder Reservoir—fell 6,500 feet into the valley below, unleashing a slurry of mud and water that inundated bridges, hydropower facilities and villages along the way. According to the United States Geological Survey, the force of the initial debris flow hitting the ground was equivalent to a magnitude 5.2 earthquake... Since the 1850s, changes in high-altitude permafrost have contributed to dozens of these cascading disasters in Nepal and parts of India, in which bedrock and glaciers break off, and trigger massive flash floods and debris flows. For example, in 2012 a slurry flood in central Nepal, similar to what happened in Nepal last week, killed 79 people along the Seti River. The University of Reading also provided the following account: Researchers from the HiRisk project, which investigates cryosphere-related hazards in High Mountain Asia, suggest that longer-term glacier retreat and permafrost degradation may have contributed to slope destabilisation. The failed glacier retreated by approximately 450m between 1990 and 2020, potentially reducing the mechanical support provided by the glacier to the underlying rock slope. Permafrost degradation may have further contributed to instability. The warmer than average temperatures observed in the area this summer might have contributed to the glacier collapse too, although observations at these elevations remain limited. As a side note, this assessment also refers to "warmer than average temperatures" during the summer. That's something the maps I posted showed in contradiction to JB's cropped map. Based on the evidence and literature: 1) A climate link is highly likely, but the magnitude of the contribution from climate change is uncertain. 2) The absence of a climate link is probably close to zero Considering the literature and emerging assessments, the burden of proof rests with those such as Martz to support the argument that climate change played no role. Arguing that climate change played no role (Martz's proposition) is quite different from suggesting that the extent of contribution by climate change remains to be determined. As noted previously, there had been record heat in the region for several days prior to the catastrophe. Moreover, frost-wedging can lead to the fracturing of rocks over long periods of time, and in the warming climate of the altitude Himalayas, this form of weathering has increased in frequency.

Following the warmest August and warmest month on record in the ERA-5 dataset, September 1 started with a global mean temperature of 16.739C. That destroyed the monthly record of 16.607C from September 1, 2024. The preliminary 0.132C difference between the new mark and the old record is the largest difference between any first and second highest monthly values.

Tomorrow and Friday will see temperatures top out mainly in the lower 80s. Showers and thundershowers are possible. Excessive heat with highs in the middle and upper 90s will be just south of the region in such cities as Baltimore and Washington tomorrow and Friday. A cooler air mass will move into the region for the Labor Day weekend. In its wake, temperatures will generally peak in the middle and upper 70s. The ENSO Region 1+2 anomaly was +4.2°C and the Region 3.4 anomaly was +2.6°C for the week centered around August 26. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +3.93°C and the ENSO Region 3.4 anomaly has averaged +2.50°C. The ongoing strong El Niño, which has reached super El Niño threshold, will continue to strengthen through the summer. The SOI was -10.63 today. The preliminary Arctic Oscillation (AO) was +0.219 today.

August 2026 finished with a preliminary monthly mean temperature of 16.957C. That would shatter the August mark of 16.823C from 2024. It would also edge past July 2023's 16.953C to become the warmest month on record in the ERA-5 dataset.

Here are the temperature anomalies for the Nepal/Tibet area. If Copernicus confirms this data for August, that will raise questions about JB's maps. Perhaps, just as with the CFSv2, they have a cold bias? August 1-25, 2026: Summer (June 1-August 25):

Parts of the region could experience a strong thunderstorm this evening or tonight. Tomorrow through Friday will see temperatures top out mainly in the upper 70s and lower 80s. Showers and thundershowers are possible. Excessive heat with highs in the middle and upper 90s will be just south of the region in such cities as Baltimore and Washington tomorrow and Thursday. A cooler air mass could move into the region for the Labor Day weekend. The ENSO Region 1+2 anomaly was +4.2°C and the Region 3.4 anomaly was +2.6°C for the week centered around August 26. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +3.93°C and the ENSO Region 3.4 anomaly has averaged +2.50°C. The ongoing strong El Niño, which has reached super El Niño threshold, will continue to strengthen through the summer. The SOI was -0.79 yesterday. The preliminary Arctic Oscillation (AO) was +0.320 today.