SIWO Forecast – Friday, April 17, 2026

Assessment of Current Ice Conditions Relevant to Distribution and Access of Walrus

Synopsis: A weak low-pressure system is moving towards Nunivak Island and is aiding in bringing gusty northeast winds through the Bering Strait and towards Gambell. This low shouldn’t bring too much precipitation outside of a stray snow shower or flurry on Friday. Temperatures will be cooling through the day on Friday, likely beginning in the low 20s and ending in the mid to upper teens. Otherwise, a stronger low pressure moves into the eastern Bering Sea southwest of St. Lawrence Island this weekend. This low will strengthen northeast winds through the Bering Strait from Friday (4/17) through Sunday (4/19) with the strongest coming Saturday night into Sunday morning (4/19). They will weaken slightly on Monday (4/20) and also shift northerly. Temperatures will be much colder with this event and highs may only get to about 15 degrees for most of next week with lows near 0 to 5 above. Wind chills may be as low as -20F to -30F at times from Monday through at least Tuesday morning. Similar to the previous event, little to no precipitation is expected. Gusty winds will prevail through at least Tuesday morning (4/21) with a much more noticeable drop-off in wind speeds through Thursday morning.

Near St. Lawrence Island

Northerly winds have opened a large polynya along the south side of St. Lawrence Island. In the last week shorefast ice around and to the east of Siknik Training Camp broke off in northerly winds. Shorefast ice between Savoonga and Gambell also broke off in the last round of southerly winds. The Shorefast ice between Savoonga and Camp Kulowiyi remained mostly intact. The northerly winds have closed much of the very open to open pack ice north of the Island. Open pack ice still remained west and northwest of Gambell all the way to the Russian coast. There is still a trace of old ice in the area that had come through the Strait earlier in the season, otherwise most of the remaining ice is a mix of first year thin and first year medium.

Nome

This area has not yet begun for the 2026 season..

Brevig Mission/Port Clarence Area

This area has not yet begun for the 2026 season.

Wales to Shishmaref

The area is currently in-between forces acting on the ice with the warmer southerly currents trying to melt and open the pack ice and northerly winds bringing the pack ice southward. A large polynya has formed off of the shorefast ice, beginning around Wales extending southward. The last round of easterly winds open some leads in the shorefast ice to the west of Shishmaref and also northwest of Espenberg. The ice closer to the coast does appear to still be shorefast.

Diomede

This area has not yet begun for the 2026 season.

Forecast Discussion

Ice Forecast

St. Lawrence Island:

Close pack ice will continue to compact against the north coastline of St. Lawrence Island. The edge of the close to very close pack ice will continue to move southward, perhaps past Gambell to the southwest. During periods of lighter winds through the week, the area to the west of Gambell could briefly open in response to the warmer currents but will be closed off again by the northerly winds and pack ice moving southward. Expect the large polynya to continue to grow along the southside of St. Lawrence Island.

Wales to Shishmaref:

Northerly winds will continue to keep consolidated pack ice compacting against the existing shorefast ice along the coast. The pack will be more mobile closer to the Bering Strait to the west of Wales. A large polynya will continue to develop to the south and southeast of Wales off of the shorefast ice.

Wind Synopsis

St. Lawrence Island:

Friday morning (4/17), north/northeast winds will be around 15-20 kts but will increase throughout the day to 25-30 kts and stay elevated until Sunday morning (4/19) when they begin to drop off. North/northeast winds will be around 20 kts by Monday morning (4/20) and continue to drop off throughout the day to around 15 kts by Tuesday (4/21) morning and continue through Thursday (4/23) morning. North/northeast winds will begin to pick up Thursday afternoon and evening and be as high as 30 kts by Friday (4/24) morning.

Wales to Shishmaref:

Friday morning (4/17), north winds will be around 10-15 kts for Shish and 17-22 kts for Wales. Winds will be increasing and by Friday evening, be as high as 20 kts for Shish and 30 kts for Wales. These are expected to persist throughout the day on Saturday (4/18). By Saturday evening, north/northeast winds will increase as high as 35 kts for Wales briefly before settling back to 25-30 kts by Sunday morning (4/19). These conditions will persist into Monday (4/20) when Wales could see another brief uptick to 35 kts again. Throughout this time Shish will continue to persist around 22-27 kts. Winds will begin to decrease Monday night and be as low as 10-15 kts by Wednesday afternoon (4/22) and persist through Friday morning (4/24).

Temperature Trend

St. Lawrence Island:

Temperatures will be warmest on Friday (4/17) with highs in the low 20s and lows in the mid-upper teens. A cooling trend arrives thereafter and lasts through at least the middle of next week. High temperatures from Saturday (4/18) through Thursday (4/23) are expected to be around 10F to 20F with the coldest days being Monday, Tuesday and Wednesday. Wind chills will also be around -15F to -25F Monday to Wednesday.

Wales to Shishmaref:

Temperatures will be warmest on Friday (4/17) with highs around 20°F and lows in the low-mid teens. Much cooler temperatures arrive on Saturday (4/18) with highs only expected to be around 10°F to 15°F. Wales will consistently be a few degrees colder than Shish with highs around 5°F to 10°F. Lows from Wales to Shish will be around 0°F to 5°F through most of the weekend and next week as well. This cooler trend from Wales to Shish will persist through at least Thursday (4/23) of next week. Wind chills are expected to be very cold, as low as -20°F to -30°F from Sunday night (4/19) through at least Wednesday afternoon (4/22).

Daily Weather, Wind, and Temperature Updates

The National Weather Service provides twice-daily, text only updates on the weather, wind, and temperature conditions in specific geographical zones. An interactive weather map for access to other Alaskan zones can be found here: http://weather.gov/anchorage/ice

Higher resolution satellite images and wind maps (wind updated daily) can be viewed here: http://www.weather.gov/afg/SIWO_overview

The Alaska Ocean Observing System shares a variety of weather and sea ice related resources in their Bering Sea Portal at https://bering-sea.portal.aoos.org/.

NWS Sea Ice Forecast Maps

Marine forecast for the West Coast and Arctic Coast

Remote Sensing Images

Observations & Comments

Observations of Local Conditions

Observations from Sivuqaq / Gambell

Tuesday, 14 April 2026 – Clarence Irrigoo, Jr.

12:02 p.m. 20° NE 35 mph

Wednesday, 15 April 2026 – Clarence Irrigoo, Jr.

15° NNE 30 mph windy and fog.

Sunday, 19 April 2026 – Clarence Irrigoo, Jr.

Winter weather advisory, 17° NNE 40 mph, Gust 55 mph

Sea ice and weather conditions near Gambell, AK. Images courtesy of Clarence Irrigoo, Jr.

Observations from Sivungaq / Savoonga

Observation from Savoonga coming soon

Observations from Kingigin / Wales

Observations from Kigiktaq / Shishmaref

Sea ice and weather conditions near Shishmaref, AK. Images courtesy of Christopher Ningeulook.

Observations from Sitnasuaq / Nome

Sea ice and weather conditions near Nome, AK. Images courtesy of Bivers Gologergen.

Observations from Scammon Bay

Sea ice and weather conditions near Scammon Bay, AK. Images courtesy of Aguchak Dexter.

Shared by the Alaska Ocean Observing System (AOOS) for 15 – 23 April 2026

The images below show animations of the movement of ice predicted by the HYbrid Coordinate Ocean Model (HYCOM). Snapshots from the forecast show ice coverage from 0% (black) to 100% (white) and arrows show the relative speed and direction of the ice. A light boundary is drawn at 15% predicted ice cover to highlight the ice edge, but ice may be predicted to extend beyond it. Some bays, lagoons, and areas very close to shore are not covered by the model. (Image produced by the Alaska Ocean Observing System / Axiom Data Science).

These animations show the predicted movement of ice predicted by the HYbrid Coordinate Ocean Model (HYCOM). Snapshots from the forecast show ice coverage from 0% (black) to 100% (white) and arrows show the relative speed and direction of the ice. A light boundary is drawn at 15% predicted ice cover to highlight the ice edge, but ice may be predicted to extend beyond it. Some bays, lagoons, and areas very close to shore are not covered by the model. (Image produced by the Alaska Ocean Observing System / Axiom Data Science)