The mean 500mb heights (30dm contours) for November 15-21 (courtesy of ESRL and NCEP/NCAR Reanalysis) show a classic pattern for cold weather in Interior Alaska, with a high over Chukotka and fairly low height northerly flow across most of mainland Alaska (I’ve added centers and arrows to indicate wind direction.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgsaFrD9Nbbr3dW9r5IA4rr91BONu8nm4IBl1C9SRwgCS1p-SIv_TpkNxAUWy3urCbVYgIQ_qM7ifIaMzFIqTiQ5XJhmnag9RcGoejuizkZXqvwdhgL4EgQLJAZYcFwAIX6FLlxOkF8OA/s320/Nov15-Nov21_2011_500.gif)
In the Fairbanks area, this was easily the coldest pre-Thanksgiving week of record. At the Airport, the lowest 7-day average temperature was -30.1F for November 15-21. The previous record was -26.5F was set November 7-13, 1989. For November as a whole, this was the third coldest event; November 24-30, 1909 and the same week in 1927 were colder.
Record lows were set at the Airport on six days (November 16th did not have a new record) and record low maximum temperatures were set November 16-19. The high temperature of -30F on the 17th is the second earliest high of -30F or lower in the winter (November 9, 1989 is the earliest). The low temperature of -41F on the 17th is the fifth earliest occurrence of -40F in the winter. Here's the plot of November record lows:
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgNAQg9YZyLbMVaWWLKD2QszOrnR9y5-M3yT5P8qoAl8uFSNDQVKOsv5lYUt_qXNy0QcIPOspBI28TixqMajnRn_UJTeENdwiumvi9wMWziQI7inckHxvU7meON0PcjrP7n9RrfUKme4g/s320/Nov_21_2911_RER.jpg)
Elsewhere around the area, temperatures varied pretty much as is typical for this time of year. The average temperature for November 15-21 at the North Pole cooperative station was -37.7F, with six days with lows in the -40s and an absolute low of -49F on the 17th. At the other extreme, Keystone Ridge cooperative station, at 1600’ MSL, had an average temperature of -13.4F the same week and an absolute low of -28F on the 21st.
Most places with a long period of observations set six or seven daily records. Lowest temperatures for the cold snap include:
University Experiment Station: -41F
Eielson AFB: -41F
UAF West Ridge: -40F
As more cooperative info becomes available I'll update the extremes.
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