A Look Across the State
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A Look Across the State
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| February 2006 Summary | ||||||||||||||||
| The Arctic Oscillation index was negative in the first and 4th weeks of the month, and positive in the 3rd week of February. As was true with January, this was an apparently mixed signal, but as was also true with January, the weather in Alaska had definitive character. The difference was the shift from cold, dry weather in January to the absolute opposite in February: a change to well above normal temperatures and above normal precipitation over most of the region. Southerly flow over the mainland strengthened in mid month, and the axis of fastest flow migrated westward. Strong southwest flow covered the mainland on the 18th through the 20th, and then turned to lighter, westerly flow. At the end of the month, the winds aloft turned to the north and brought in colder air from the Arctic. Vigorous inflow of Pacific air to Southeast Alaska was limited to the first half of the month, and was followed by generally dry northwesterly flow. |
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| In the Arctic, the month began very much on the cold side. On the 3rd, Point Lay set a new all time record of -56°F, and the -55°F at Barrow was just 1ºF above the all time record there set in 1924. However, by the 5th southwest winds brought in significantly higher temperatures, which over the next two weeks rose 80 to 90°F, to around freezing in the 3rd week of the month. The continuation of this pattern of winds aloft brought overall February temperatures in the Arctic to an astonishing 6 to 20°F above normal. Precipitation totaled over three times normal in the west and 2 to 3 times normal in the east. Barrow had record high temperatures - from 30 to 35°F - in the 3rd week of the month. At the end of February, Barrow had 18” of snow on the ground, an amount far above normal for an area with a dry climate (the average annual precipitation at Barrow is only 4.16”.) The west coast had frequent southerly inflow of mild Pacific air, leading to overall monthly temperatures from 6 to 12°F above normal. Precipitation ranged from just above normal at Bethel to 2.5 times normal at Nome. In the Aleutians and the southeast Bering Sea, temperatures were about 1°F above normal, and in the southeast Bering Sea, precipitation was from 130 to 140% of normal. Record cold at King Salmon on the 2nd (-43°F) was replaced by record warmth on the 15th (46ºF) - a rise of 89°F. In Norton Sound, high temperatures and strong south winds combined with a high tide pushed a flood of sea water up on the ice in the Sound on the 15th. Several participants in the Iron Dog snow machine race drove through the overflow en route from Unalakleet to Nome. Two went into water waist deep and it took the combined effort of racers to pull the machines out. A few of the racers sped up to about 60 mph when they saw water approaching, and hydroplaned across. Miraculously, everyone made it safely into Nome. The Interior weather changed completely from the cold dry conditions of January. For instance, the average February temperature at Fairbanks was 30ºF above January's average. Prolonged inflow from the south starting on the 4th brought temperatures above normal everywhere in the region for the rest of the month. Overall, temperatures ranged from 2 to 4°F above normal in the southeast to 8 to 16°F above normal over most of the Interior, and as much as 23°F above normal in the Brooks Range to the north. During the 3rd week of the month, record high temperatures - in the 30's and 40's above - were observed at a number of stations. Precipitation ranged from less than 50% of normal along the Yukon border to above normal values in nearly all areas to the west. The upper Koyukuk Valley had more than 3 times its normal precipitation for February. Much of the central Interior had its heaviest February snowfall in a full decade. A westerly blizzard hit the highlands northeast of Fairbanks on the 15th, leaving several teams in the Yukon Quest sled dog race stranded in the hills until the weather calmed. On the l9th, widespread snow and some freezing rain came in by a weather front from the Bering Sea; these were blamed on a large number of traffic accidents around Fairbanks. A significant snow and wind storm came on the 25th and 26th, as a strong weather front from the Bering Sea was followed by vigorous westerly inflow of maritime air. Anywhere from 1 to 2 feet of snow fell over a wide swath of the region, especially in the northwest. The southern mainland had temperatures were 1 to 5°F below normal on the North Gulf coast and as much as 8°F warmer than normal farther north in the Alaska Range. Precipitation was as low as 50% of normal on the North Gulf coast and from 100% to more than 200% of normal farther north in the Copper River basin. On the 10th, heavy snow and whiteout conditions in high winds closed the Seward Highway south of Girdwood. There were at least 2 avalanches on to the road. Also resulting from this storm were a large number of vehicle accidents, wind damage to some buildings, and power outages. Abundant snowfall and a big rise in temperatures at the end of a cold snap resulted in some large avalanches in the south central Alaska mountains. The Seward Highway 21 miles outside of Seward was closed on the 11th by a huge avalanche that buried the road under snow as much as 30 feet deep. Two other avalanches had occurred farther north on the 10th. On the 28th, a snow boarder on Marmot Mountain, about 55 miles north of Anchorage, was killed when he was buried in an avalanche. And a snow slide in Rainy Pass on the 14th killed a man. Organizers of the Iditarod dog sled race subsequently had some of the mountainsides triggered with explosives to bring unstable areas of snow down before the race. In southwest Cook Inlet, eruptions of Mount Augustine tapered off to relatively minimal activity by month's end. Southeast Alaska had inflow of Pacific air less vigorous and less frequent than the usual pattern. Temperatures were mostly 1 to 4°F cooler than normal, though a few stations reported values from 1 to 2°F above normal. Precipitation was generally 40% to 100% of normal. Unstable soils on a mountain side in Juneau let loose an automobile sized rock, which knocked a house from its foundation on the 14th. |
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Statewide Extremes
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Statewide Temperature and Precipitation
Departure Maps |
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| Marine weather continued to be rough and active. On all but 2 days of the month, there were gale force winds blowing somewhere in Alaska's vast ocean waters. Three storms of the month came on the 4th-5th (Bristol Bay and the west Gulf of Alaska), on the 9th (west Gulf of Alaska), and on the 13th (central Aleutians.) All 3 episodes produced central pressures down near 956mb (28.23”), storm force winds, and high seas. The other storm of the month was a 970 mb (28.64”) low that moved northeastward, and moved across Barrow on the morning of the 19th. Sea surface temperatures in the Gulf of Alaska were 1 to 2°F above normal in the east and near normal in the west. In the Bering Sea, temperatures ranged from near normal in the south to 1 to 2°F cooler than normal in the central Bering Sea and in Bristol Bay. Sea ice coverage was well above normal on the 1st, at which time it was just ashore on Saint Paul Island. The maximum extent of ice in the Bering Sea for the season was reached on the 10th, as the edge of the pack ice reached Saint George Island. The ice cover was already starting to recede in Bristol Bay on the 10th. Warm weather for the rest of the month melted the ice pack in the Bering Sea and Bristol Bay at a rapid rate. By the 15th, the extent of ice cover had been reduced to below normal. On the 28th, the pack ice in the Bering Sea was well below normal for the end of February, while the ice had recovered to a near normal extent in Bristol Bay. In Cook Inlet, the ice extended down past Kenai during the first week of the month, and expanded to cover the entire western shore on the 8th. By month's end, the ice edge had advanced southward to Ninilchik. On the 2nd, the 600 foot oil tanker Seabulk Pride was torn from its moorings at the Port of Nikiski by heavy ice floes in a strong tidal current. The ship was then grounded on a nearby beach, where it remained until floated free on a high tide on the 3rd. There was no oil spill resulting from this incident. |
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Summary information is compiled and produced monthly by the Fairbanks Forecast Office of the National Weather Service and the Alaska Climate Research Center, with contributions by Ted Fathauer, Anton Prechtel, and Martha Shulski. Portions of this summary appear in Weatherwise magazine. Preliminary climatological data are used for the graphical products. For official data, please contact the National Climate Data Center. |
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