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Sea Ice Outlook for Western and Arctic Alaskan Coastal Waters 

National Weather Service Anchorage Alaska 

1128 AM AKDT Sunday 24 December 2023



...DECEMBER 2023 MONTHLY SEA ICE OUTLOOK...





The biggest change over the last month is the closing-off and 

subsequent freeze-up of the Chukchi Sea. While the air mass over the 

area was plenty cold to support new growth, stronger winds through 

the Bering Strait prevented a widespread flash freeze early in the 

month. However, high pressure during mid-December allowed for the 

Chukchi Sea to freeze up. 





Shorefast ice along the North Slope continued to become established, 

thickening to first-year thin in most areas as well as growing out 

from the coast. The shear zone between the shorefast and the pack 

has become established. Norton Sound became completely ice covered 

with mostly new and young ice. Most of the west coast remained in a 

growth regime with ice expanding from Cape Newenham through Wales, 

growing out from the coast. Ice around Bristol Bay was the last to 

become established, and has finally joined with the remainder of the 

Bering Sea ice. 





Looking farther into freeze-up, El Nino conditions will persist and 

strengthen through the coming winter and likely into spring 2024. So 

far this winter, El Nino hasn’t slowed freeze-up much, though that 

can change quickly with the storm track. Expect the southern Bering 

Sea to remain highly variable. 





Detailed information can be found in each pertinent section below.





...FREEZE-UP OUTLOOK FOR THE BERING SEA...





Sea ice is expected to extend beyond Nunivak Island during the 

fourth week of December.





For Bristol Bay, seven tenths coverage is expected during the first 

half of January. It is likely that sea ice extent will vary 

significantly within Bristol Bay through the 2023-2024 sea ice 

season based on prevailing storm track.





The ice edge is expected to reach Saint Matthew Island during the 

first week of January, but will be largely dependent on the exact 

setup of storm tracks over the next month.





The ice edge is not expected to reach Saint Paul Island this season 

but if it happens it will be late in the season. 









...FREEZE-UP OUTLOOK FOR COOK INLET...





Sea ice in Cook Inlet is very dependent on the prevailing ambient 

air temperature. El Nino winters tend to be warmer than average, so 

freeze-up dates will likely be later than the past three winters and 

sea ice extent will likely be variable through the winter as 

temperatures fluctuate. So far this season, while there has already 

been one warm Chinook event, air temperatures have otherwise been 

low enough to get ice started in the upper Inlet. 





While there has been some ice forming on mudflats and in protected 

areas, the first established ice south of the Forelands is expected 

around mid-January.





North of the Forelands, three tenths ice coverage is expected during 

the last week of December. Seven tenths coverage is expected during 

the third week of January.





The first ice along the coast from Kenai to Nikiski is expected 

during the third or fourth week of January.





The ice edge is expected to reach Kalgin Island during the second 

half of January. If warm air is persistent across the Cook Inlet 

region, the ice edge may not reach Kalgin Island until early 

February.





From 60N to the Forelands, three tenths concentration is expected 

during the first half of February. Seven tenths concentration is 

expected around mid-February. 





Sea ice may reach Ninilchik during the first half of February.





Sea ice is not expected to reach Anchor Point this season.





$$

Lawson