LEO Network
19 December 2017

Slow River Freeze Up and Difficult Travel Conditions

The weather in Galena, Alaska has been warmer than average this fall and winter, resulting in late river ice freeze-up and difficult travel conditions due to open holes in the river ice and overflow on lakes and sloughs. Observations from Lower Kalskag and Chuathbaluk also reported open water in both the Yukon and Kuskokwim rivers. The National Weather Service (NWS) has received observations of warm winter weather from this region since 2013 and maintains historical freeze-up records. The observation has been forwarded to the NWS and the Alaska River Forecast Center for consultation. The low accumulated freezing degree days this autumn are in line with community observations and climate data, which help define freezing degree day values that are too low to allow for a good freeze-up. The NWS is responsible for monitoring ice breakup conditions throughout Alaska to assess flood threats and navigational hazards.

Observation by Karin Bodony:

The weather this fall and winter has been warmer than average and river ice on the Yukon at Galena did not stop moving until very late (among the latest dates on record). Continued warm weather and snowfall have made travel away from the villages very difficult and dangerous due to open holes in the river ice and large amounts of overflow on lakes and sloughs.

Comments from LEO Editors:

This observation has been added to the project Extreme or Unseasonable Weather. Since 2013, LEO has received observations of warm winter weather from this region. This year, observers in Lower Kalskag and Chuathbaluk also reported open water in both the Yukon and Kuskokwim rivers. Looking at data from the National Weather Service (NWS), temperatures were above average throughout November. NWS maintains historical freeze-up records. This observation has been forwarded to the NWS and the Alaska River Forecast Center for a consult.

Rick Thoman, Alaska Region Climate Science and Services Manager, writes:

The open rivers/late freeze-up and fog are a response to the very mild autumn. At Bethel, this autumn has had, thru Dec. 19th, the lowest accumulated freezing degree days (a measure of accumulated cold) of any year since 1925. At McGrath, this is second-lowest accumulated freezing degree days since 1941 (only 2002 was lower). So these community observations are right in line with the climate data and help define freezing degree day values that are too low to allow for a good freeze-up.

Resources:

National Weather Service (NWS) is responsible for monitoring ice breakup conditions throughout Alaska to assess flood threats and navigational hazards. Ground observations, aerial reconnaissance, and remote sensing are sources used to assess ice conditions. Although ice jam flooding is most common during the ice breakup season, ice condition reports are welcome during freezeup and mid-winter as well. (NWS River Watch Program)

Media:

Anchorage Daily NewsWith warm December winds, shaken faith in Arctic weather: "Folks here are famous for being able to handle the cold, but anything wet in December has always made us nervous. Especially wet falling from the sky. Lately, weather, our favorite nemesis, has broken the rules. Our confidence in the most trustworthy feature of the Arctic--winter--has been wounded. If anyone starts to forget that, all they have to do is look at the mess of ice shoved up against Front Street, or walk out in the pouring rain..." By Seth Kantner. December 10, 2013.

Galena, Alaska, United States


Alaska Divisional Average Temperature Ranks, November 2017
NOAA National Centers for Environmental Information
Freeze Up Data for the Yukon River at Galena
National Weather Service
Weather
Surface Waters / Wetlands
Ice / Snow Change
Transportation
Seasonal Timing