A “spectacular chinook” warms Fairbanks, Alaska
The temperature at Fairbanks International Airport dropped to -44 degrees (44 below zero) on Sunday, the last day of a continuous 16-day freeze-up, the coldest spell in the last 50 years. By Wednesday, the temperature reached a record high of 44 degrees, dramatically reversing the trend from one extreme to another. The temperature difference of 88 degrees was reached in just three days.
“Incredible,” said meteorologist Rick Thoman at the National Weather Service in Fairbanks. “Is there any other place in the country that can do that?
Adiabatic warming of downward moving air produces the warm Chinook wind. Chinook is a Pacific Northwest Indian word meaning ‘snow-eater,’ as a strong Chinook can make foot deep snow almost vanish in one day. The snow partly melts and partly evaporates in the dry wind. Chinook winds have been observed to raise winter temperature, often from below −20°C (−4°F) to as high as 10°C to 20°C (50°F to 68°F) for a few hours or days, then temperatures plummet to their base levels. The greatest recorded temperature change in 24 hours was caused by Chinook winds on January 15, 1972, in Loma, Montana; the temperature rose from -48°C (-56°F) to 9°C (49°F), a difference of 105 degrees (source: wikipedia).
“It’s just a spectacular Chinook,” he said.
This spectacular Chinook Arch appeared over Calgary in the late afternoon of January 6, 2003 – during a warm spell when the temperature in the city reached an all-time January record high of 18°C (64°F). Image Credit: CalgaryWikifan. Wikipedia. GNU Free Documentation License, Version 1.2 or later versions.
In Nenana, the temperature rose to 54 degrees Thursday morning, another all-time high, Thoman said.
The previous record high at the airport was 43 degrees set in 1981. Also, the temperature at Birch Lake reached a daily record high of 54 ºF.
“There’s July days when it’s not that warm at Birch Lake,” Thoman said.