Extreme Temperatures
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Helicopter

Avalanche hits helicopter near Verbier, Switzerland, leaving 3 people dead

The site of the accident.
© Kantonspolizei Wallis/ValaisThe site of the accident.
A fatal helicopter accident was reported on Tuesday, April 2, at Petit Combin, near Verbier, Switzerland. Three people lost their lives in the accident while three further people were injured.

According to the police report, a type B3 helicopter crashed at the Petit Combin, a popular backcountry and heliskiing location near the famous Verbier Ski Resort, around 9:25 a.m. The helicopter was taking four guests and a guide for a heliskiing trip and was manned by one pilot. While the police report stated that 'unspecified reasons' caused the helicopter to slide off the peak of the Petit Combin at 3,668 meters (12,034 feet), eyewitnesses reported to British newspapers that an avalanche sent the helicopter down the north wall of the Petit Combin. The slope from Petit Combin runs at an angle of between 40-45°.

Snowflake

Mammoth Mountain, California, receives 3 feet of spring snow in 3 days

snow
Spring, who?

Yesterday, Mammoth Mountain, California, announced it had received three feet of snow in three days.

Another three to four inches of snow have fallen at Mammoth in the past 24 hours.

Today's weather is mixed, with warmer temperatures, blue skies, and winds that could impact upper mountain lift operations.


Arrow Down

Swiss avalanche at Riffelberg, near Zermatt Alps resort, kills three

The avalanche broke below a lift on the Riffelberg.
The avalanche broke below a lift on the Riffelberg.
Three people have been killed and another person injured in an avalanche at Riffelberg, near the Swiss Alpine ski resort of Zermatt.

Footage on social media showed a wall of snow crossing an off-piste sector of the Riffelberg sector of Zermatt, one of the most luxurious ski resorts in the Alps.

Authorities launched a major rescue operation despite bad weather but it was later suspended.

Heavy snowfall and very strong winds had prompted authorities to warn of a major avalanche risk in the southern Swiss Alps.

The risk was considered especially high in the Grisons and Valais cantons, both popular ski destinations.


Arrow Down

Snowboarder killed in avalanche at Mount St. Helens, Washington

Mount St. Helens is seen from the Hummocks Trail, on May 18, 2020
© Ted S. WarrenMount St. Helens is seen from the Hummocks Trail, on May 18, 2020
A snowboarder was killed Saturday in an avalanche at the summit of Mount St. Helens, the Northwest Avalanche Center said in a preliminary report.

Standing near the mountain peak, the snowboarder triggered the avalanche on a cornice — an overhang of snow that can form on steep alpine slopes — and fell to his death.

"Our deepest condolences to the family, friends, and community," the avalanche center wrote in a post on its website.

Large cornices are more likely to fail during warmer weather, the agency said. According to the website, moderate avalanche danger was forecast this weekend in mountains throughout Washington.

The avalanche center will work with the Skamania County Sheriff's Office and search and rescue to compile a full report.

Bizarro Earth

The extraordinary climate events of 2022-24

Hunga Volcano
© judithcurry.comFigure 1. The Hunga Tonga eruption from space.
The unlikely volcano, the warmest year, and the collapse of the polar vortex.

The climate events of 2022-24 have been were truly extraordinary. From an unlikely undersea volcanic eruption to the warmest year on record to the collapse of the polar vortex after three sudden stratospheric warming events. This rare convergence presents a unique learning opportunity for climatologists and climate aficionados alike, offering insights into a climate event that may not be repeated for hundreds or even thousands of years.

1. January 2022, the unlikely volcano

Never before have we witnessed an undersea volcanic eruption with a plume capable of reaching the stratosphere and depositing a large amount of vaporized water. This extraordinary event occurred in January 2022 when the Hunga Tonga volcano erupted. The conditions for such an event are rare: the volcano must be deep enough to propel enough water with the plume, but not too deep to prevent it from reaching the stratosphere. Most undersea volcanoes do not produce plumes at all, which makes Hunga Tonga's eruption all the more remarkable.

The Hunga Tonga volcano occupied a unique "sweet spot" at a depth of 150 meters the day before the eruption. In addition, the eruption itself must be exceptionally powerful for water vapor to rise into the stratosphere. The January 2022 eruption of Hunga Tonga was the most powerful in 30 years, since the 1991 eruption of Mt. Pinatubo.

Active undersea volcanoes at the appropriate depth are rare, and the likelihood of one erupting with such intensity is relatively low. We may be looking at an event that occurs once every few centuries, or maybe even once every millennium. Undoubtedly, it was an exceptionally rare event.

While the most powerful eruptions, such as Tambora in 1815, can indeed strongly influence hemispheric weather for a few years, our observations of eruptions such as Agung (1963), El Chichón (1982), and Pinatubo (1991) suggest that their effects dissipate within 3-4 years.

Snowflake

High avalanche danger in southern Alps following over 2 feet snowfalls in 24 hours

Vars has received 60cm (2 feet) of snowfall in 24 hours.
Vars has received 60cm (2 feet) of snowfall in 24 hours.
The avalanche danger has jumped from level 2 ('moderate') to a 'high' level 4 on the scale to 5 at ski areas across the region after several reported over two-feet (60 cm) of snowfall in about 24 hours on Tuesday-Wednesday this week.

Isola 2000, Serre Chevalier and Risoul-Vars in the southern French Alps were among the areas posting 60cm (24") accumulations on their higher slopes, with Les 2 Alpes also noting that the avalanche danger there had jumped to level 4.


Snowflake

Best of the Web: Wild swings: Snow falls on Malaga in southern Spain following a dramatic drop in temperatures overnight

mmmm
Parts of Malaga have woken up to a blanket of fresh snow following a dramatic drop in temperatures overnight.

Whilst low-lying coastal areas have experienced much-needed significant rainfall, Malaga's high altitude areas have been hit by snowfall.

This morning, many of the region's mountains were covered in snow after unseasonably low overnight temperatures.

Snow settled in the Sierra de las Nieves, Sierra Tejeda, Sierra Bermeja and the Torcal de Antequera National Park.

Snow was also visible from the cities of Ronda and Granada.


Comment: Related: Temperature extremes: From 30ºC to snow fall in Portugal


Snowflake

Best of the Web: Temperature extremes: From 30ºC to snowfall in Portugal

From 30ºC to snow fall
From 30ºC to snow fall
Several areas woke up covered in snow this morning, including Gerês, Paredes de Coura and Arouca.

Snow fell again in several parts of the country, after several days with thermometers tipping the 30ºC mark.

Castro Laboreiro, in the municipality of Melgaço, woke up painted white after the snow fell during the afternoon and night of Monday.

In Cabana Maior, Arcos de Valdevez, right on the doorstep of the Peneda-Gerês National Park, it also snowed, with several online users sharing images.


Comment: Related: Snow falls on Malaga in southern Spain following a dramatic drop in temperatures overnight


Snowflake

Over 2 feet of snow, flooding pummel Northeast US with more than 350,000 power outages

Snow falls in Plymouth New Hampshire on March 23, 2024.
Snow falls in Plymouth New Hampshire on March 23, 2024.
A strong coastal storm made for a washout during the first half of the weekend with a steady drumbeat of heavy rain and gusty winds across the Northeast's Interstate 95 corridor while heavy snow piled up in New England.

Rain began falling across the coastal regions on Saturday morning and only increased in intensity into the afternoon and evening as the storm's center swirled just off New York City and Boston.

Where temperatures were cold enough, precipitation fell in the frozen variety, and there was a lot of it.

Some snow totals eclipsed 2 feet in the higher elevations of New England.

Albany, New Hampshire, reported 28 inches of snow while Ludlow, Vermont, saw 27.3 inches pile up.


Bizarro Earth

The Polar Vortex is spinning backwards

Earlier this month, atmospheric scientists noticed something unusual in the Arctic stratosphere. The polar vortex was spinning backward.

"The vortex changed direction around March 4th," reports Dr. Amy Butler, author of NOAA's Polar Vortex Blog. "It was a substantial reversal, reaching -20.5 m/s a few days ago, which puts it in the top 6 strongest such events since 1979."
Polar Vortex
© NOAA Climate Gov Data: Waugh et al 2017
Two weeks later, it is still spinning backwards. What's going on?

"Atmospheric planetary waves have been breaking in the polar stratosphere, increasing its temperature," says Butler. "We call this a 'Sudden Stratospheric Warming' event, and it can cause the vortex to change direction.'"

In recent years, many people have heard the phrase "polar vortex" because of the effect it can have on winter weather. When the polar vortex is strong and stable, it helps confine cold air to polar regions. When the vortex weakens or becomes disturbed, cold air spills out to lower latitudes.