The Northern
Climate Observer

The Big Storm - October was the month of ex-Typhoon Halong, which plowed ashore on the 11th, with winds of over 100 mph and a storm surge exceeding 6 feet above the high-water line. The devastation was unprecedented. Forty-nine communities were impacted with the greatest devastation in the low-lying areas of the Yukon-Kuskokwim Delta. In Kipnuk, up to 90% of the homes were severely damaged or destroyed. Some were swept off their foundations and sent floating away with people inside. One person died and two are still missing. Over 1,600 were displaced and evacuated to other communities, Bethel or Anchorage. As the response continues and new storms gather in the distance, Alaskans are trying to understand how storms formed thousands of miles away in the tropics, could arrive here with such fury. Has something changed? Are we more vulnerable to these storms than in the past?

This storm was born in the north Philippine Sea on October 5th, 2025. Upon reaching winds of 39 mph, it was given a name, "Halong", which means 'descending dragon' in Vietnamese. Fed by warm, moist tropical air Halong grew stronger and soon reached "typhoon" status, with winds exceeding 74 mph. On October 8th, Halong reached its peak strength with winds of approximately 138 mph. As it continued north out of the tropics, Halong started to transform into a very large, very powerful low-pressure system known as an 'extratropical cyclone' or 'ex-typhoon.'

I asked our friend Rick Thoman from the Alaska Center for Climate Assessment and Policy about ex-typhoons in Alaska. According to Rick, these storms are nothing new, but they usually only impact as far north as the Western Aleutian Islands, and less commonly the Pribilof Islands, Southcentral, or Southeast Alaska. They generally do not have the sustained power to reach further north. Prior to 2022, only one ex-typhoon (Carlo in 1976) traveled all the way from the Western Pacific to the Chukchi Sea. But things have started to change. Since 2022 there have been three: Merbok in September 2022, Ampil in August 2024, and now Halong.

So, what's changed? We know that Merbok was fed by warm surface ocean temperatures, creating a conveyor to sustain the storm through the Bering Sea and into the Chukchi. How much water ocean temperatures may have contributed to Halong's journey has yet to be determined. We can say, however, that the conditions were primed. This year the North Pacific experienced its hottest summer on record, with surface temperatures exceeding the previous record set in 2022.

These storms are a wake-up call for the growing risk posed by ocean warming. Storms forming in the tropics are now traveling almost annually across the Pacific and all the way to the Arctic. The warmer the ocean temperatures become, the higher the storm risk for communities in Alaska, and in other parts of the circumpolar north. Mike Brubaker, Editor

Storm “Amy” is bringing red and orange warnings for wind and rain in southern and eastern Norway, isolating Utsira and Kvitsøy after ferry cancellations. Authorities and aid organizations have raised preparedness, with disrupted roads, flights and events, and advice for residents to secure items and stock essentials.

A viral video shows Big Lake near Huslia rapidly eroding and draining into the Koyukuk River, alarming residents who say recent high water and thawing permafrost are accelerating change. Locals fear the erosion could threaten parts of town built near the lake.

A cyclone brought wet snow and wind gusts up to 28 m/s to Chukotka, causing power outages, water supply disruptions, and widespread flight delays. Ferry service across the Anadyr Estuary was suspended in the morning, with plans to resume service later in the day.

Flooding had already begun by Wednesday afternoon, and the weather service forecast said water could rise as high as 10 feet above the high tide line. Flood waters are expected to peak around 8 p.m. Wednesday.

A powerful, ongoing storm in Western Alaska has flooded communities, destroyed homes and left some residents injured by flying debris. Officials say rescue efforts are underway after floodwaters in multiple communities swept homes off their foundations. The remnants of Typhoon Halong tracked farther east than expected, slamming into the Yukon-Kuskokwim Delta coast early on Sunday morning. Officials said Sunday afternoon that the hardest hit communities appeared to be Kipnuk, Kwigillingok and Napakiak.

A mosquito species, Culiseta annulata, has been confirmed in Iceland after specimens of both sexes were captured in Kjósarhreppur on October 16–18, 2025. The find suggests mosquitoes may now be present in the country, long considered free of them.

A Tennessee warbler (Leiothlypis peregrina) was captured and identified at Mølen in Vestfold after Storm Amy, marking the first record for Scandinavia. Ornithologists believe it was carried across the Atlantic by strong jet streams; birders rushed from around Norway to see it, though it is unlikely to survive the Norwegian autumn.

Norton Sound Health Corporation issued an air quality alert for Nome after PM10 levels exceeded 301 (hazardous) on Oct. 23. Officials cite recent freeze–thaw cycles and dry conditions for the unusual late-October dust; residents are advised to limit outdoor exposure and use N95 masks.

Prolonged drought has driven Mackenzie River levels near Fort Simpson, N.W.T., to historic lows, turning a community boat launch into a sandbar and making fall hunting by river hazardous. A territorial hydrologist cites climate change, El Niño, and upstream dams as contributors, while local leaders urge stronger action and monitoring.

Iceland experienced intense cold overnight, with -19.8°C recorded at Sandskeið around 6 a.m., and meteorologist Einar Sveinbjörnsson says it is likely the coldest 30 October on record. Reykjavík dropped to just over -8°C, and an Icelandic Met Office table showed -20.2°C at Setur south of Hofsjökull overnight.