Ice Storm — Pribilof Islands, Alaska

1999-03-18 · Pribilof Islands, Alaska

Wider weather episode

An extremely intense storm moved up toward the extreme Western Aleutians late Tuesday continuing to just south of Adak as a 946mb center 9pm Wednesday. The low began an eastward turn while starting to very slowly weaken during the next 24 hours...moving to 180 miles south of Cold Bay as a 959mb center at 9 pm Thursday. Thereafter, the low weakened more rapidly, locating about 240 miles south southeast of Kodiak as a 975 mb center at 9pm Friday.Very strong west and northwest winds were reported on the back side of the low throughout the period, primarily affecting the central and Western Aleutians and the Pribilofs. The F/V Lin-J, a 96 foot crabber, capsized with 5 persons on board Thursday afternoon (1 body found, others presumed dead). Extremely strong southeasterly winds preceded the front, which moved northeastward through the central Aleutians Thursday morning, weakening in a large arc through Kuskokwim Bay to Turnagain Arm into the northeast coast of the Gulf of Alaska at 9am Friday.Initially, winds in advance of the front reached 80 to over 100 mph across the Aleutians, the Pribilofs and the Alaska Peninsula late Tuesday and Wednesday...causing blizzard conditions in snow and blowing snow across most areas. Blizzard conditions and winds 60 to 75 mph were also reported along the back side of the low across the central and western Aleutians, mostly west of Dutch Harbor, and the Pribilofs.Further east, wind gusts, channelled by terrain, reached an ASOS adjusted 97 mph at the Portage Visitor Center between 9pm and 11pm Thursday and 81 mph (ASOS adjusted) at Middleton Island early Friday morning as the front approached. Winds at the Cordova Small boat harbor recorded a very strong 115 mph wind gust on Thursday (local conditions) as the front approached. Significant winds also made it into higher terrain of the Kuskokwim Valley...where AWOS adjusted gusts reached 52 mph at Sparrevohn AFB.Following are some of the peak winds observed:Place Date Time Wind (mph) RemarksAleutians (zone 20)Adak 3/17 7am - 9am East southeast 63 Fropa 10:15 am/wind diminished 3/18 9am & 1pm Northwest 68Shemya 3/17 6am - 9pm North northeast 104 Strongest wind reportDutch Harbor 3/17 7pm-8pm East southeast 82 Blizzard noon - 7:30pmPribilofs (zone 21)Saint Paul 3/17-18 7pm-1am East gust 70 Blizzard/gusts finally below 40 mph Friday morning. Boat sinking/5 deaths.Saint George 3/17 10pm-11pm East northeast 81 BlizzardAlaska Peninsula (zone 19)Cold Bay 3/17 10pm-11pm East southeast 81 Winds channelled by terrainBristol Bay (zone 16) & Kuskokwim Delta (zone 11)Cape Newenham 3/18 12:30am East southeast 58Kuskokwim Valley (zone 12)Sparrevohn AFB 3/18 noon East 45 1500+ feet above sea levelKodiak Island (zone 18)Kodiak 3/18 3pm-4pm East southeast 58Cook Inlet (zone 15)Portage 3/18 9pm-11pm East southeast 97 Glacier induced/channelled windCentral Gulf Coast (zone 17)Middleton Island 3/19 4am-5am East 81Snowfall in advance of the front from Thursday morning through Friday morning reportedly ranged from 8-20 inches at the Silvertip highway camp at milepost 57 of the Seward Highway. Snowfall around Seward was reported from 12-14 inches. Homer received another 8-10 inches of snow during the 24 hour period from Thursday morning to Friday morning. Heavy snow was also reported around Whittier Friday afternoon, with 29 inches of snow received during the prior 24 hours (total of 11 feet on the ground).An avalanche was reported at mile 37 of the Seward Highway at 5:30pm...resulting in nearly 18 feet of snow on the Seward Highway. Workers managed to clear a single lane by 11am Friday. By 3:30 pm the whole highway was reopened. Additionally, the Department of Highways closed off the Sterling Highway until around noon Friday due to avalanche risk.

Source: NOAA Storm Events Database, event_id 5681122. Narrative written by the NWS forecast office that issued the report.