Alaska Weather Summary - December 2012

January 9, 2013

Weather information for Fairbanks, AK, December 2012For December, temperatures were markedly colder than normal. All nine stations discussed in this summary reported below normal average temperatures. The greatest negative deviation was observed in Fairbanks at an astonishing minus 13.2 degrees Fahrenheit, followed by Delta Junction (minus 10 degrees), Juneau (minus 6.4 degrees), then King Salmon and Nome (minus 6.2 degrees). The mean deviation for all stations was minus 5.8 degrees Fahrenheit.

 

Precipitation was mixed, with just three stations reporting above normal totals, while the other six had precipitation deficits. Expressed as percentages, Fairbanks reported the greatest positive deviation with 186 percent above normal. Delta Junction was the relatively driest station with just 34 percent of the normal amount of precipitation. The mean deviation of all nine stations was near average at just 3 percent below normal.

 

In Fairbanks, the average temperature for December was minus 17.3 degrees Fahrenheit, an astounding 13.2 degrees below the long-term mean and the second coldest December in the last 30 years. The lowest temperature for the month was a bone chilling minus 48 degrees on the 17th. The month’s highest temperature was a balmy 34 degrees on the 31st. This was 82-degree increase in temperature two weeks. The cold spell from November continued into the beginning of December. The month warmed up for five days around the 11th and then stayed cold until the last week of December. Ten days hit lows at minus 40 degrees or colder. No new record temperature events were recorded.

 

Precipitation was above normal in December for Fairbanks, with a total of 1.19 inches, 0.55 inches above the expected value of 0.64 inches. Snowfall totaled 18.5 inches for the month, which was 12.1 inches above normal. From December 9 to 14, there were 18.2 inches of snowfall. A new record snowfall occurred on the 12th, with 9.5 inches. This amount topped the 1972 record of 5.7 inches. In conjunction, December 12 saw a new record precipitation total of 0.72 inches. With the protracted winter storm, Fairbanks had nearly eliminated its winter snow deficit. The mean wind speed was 1.1 mph, with a maximum gust of 26 mph on the 13th. The gust blew from a westerly direction.

 

In Delta Junction, the mean temperature for December (minus 7.9 degrees Fahrenheit) was an astonishing 10 degrees below the long-term normal of 2.1 degrees. The highest temperature of the month was 40 degrees observed on the 29th. The lowest temperature of the month was minus 43 degrees Fahrenheit observed on the 4th. Temperatures started the month with below normal values, followed by a brief warm spell around the 11th. Temperatures then stayed cold until the last few days of December. No new records were set, and precipitation was very light. The reported precipitation total was 0.13 inches, a mere 34 percent of the expected amount.

 

The average temperature in Juneau for December was 23.5 degrees Fahrenheit, 6.4 degrees below the long-term mean. This was also the eighth consecutive month with below normal temperatures for the community. The month’s maximum temperature was 39 degrees on the 13th. The month’s minimum temperature was 3 degrees, which occurred on the 21st and 22nd.

 

Total precipitation in December was lower than normal at 4.92 inches. This amount represents only 84 percent of the expected amount of 5.84 inches. December was the third month in a row with below normal precipitation. Despite the low total precipitation, there was a record rainfall on December 30 with 0.81 inches, topping the 1989 record of 0.77 inches. Total snowfall for the month was 27 inches, 11.4 inches above normal. Due to the below normal temperatures, more precipitation fell as snow than expected. This explains the below normal precipitation and the above normal snowfall. The average wind speed was 6.7 mph. The month’s maximum wind speed was 41 mph and occurred on December 14. It blew from a southeasterly direction.

 

Anchorage was cooler than normal in December, with an average temperature of 14.6 degrees Fahrenheit. This was 4.4 degrees below the expected temperature. The maximum temperature was 47 degrees and occurred December 30. The month’s minimum temperature, minus 9 degrees, occurred on the 17th. December temperatures tended to be colder than normal, with the exception of a few days around the 11th and then at the end of the month.

 

Precipitation was high at 1.83 inches, 65 percent above the normal of 1.11 inches. Snowfall totaled 18.2 inches, just 1.5 inches above the expected amount. A new snowfall record occurred December 12, with 8.6 inches falling. This snowfall broke the 6.8-inch record set in 2011. With heavy snowfall from December 8 to 12, Anchorage had nearly eliminated its winter snow deficit. The average wind speed was 6.6 mph, with a maximum wind speed of 43 mph. That maximum gust was reported on the 29th and blew from a southerly direction.

 

For Barrow, December was the first month in the last nine with a below normal mean temperature. The mean value was minus 9.5 degrees Fahrenheit, a deviation of 1.7 degrees below the normal of minus 7.8 degrees. Warm temperatures started the month, but then remained colder than normal until the 20th. The lowest temperature, minus 32 degrees, occurred December 15. The month’s highest temperature was reported on the 1st. It was 11 degrees.  

 

Precipitation in Barrow was half of the normal value of 0.14 inches. The average wind speed was 11.8 mph. The month’s maximum gust was 43 mph and occurred on the 24th. It blew from an easterly direction.

 

In December, Ketchikan reported an average temperature of 34 degrees Fahrenheit, 1.3 degrees below the long-term mean. The month’s maximum temperature was 45 degrees, which occurred on the 31st. The month’s minimum temperature was reported on the 23rd and 26th. It was 19 degrees. 

 

Precipitation was light in Ketchikan, totaling 9.86 inches. This was just 69 percent of the long-term mean of 14.23 inches. 

 

The average temperature for December in King Salmon was 12.4 degrees Fahrenheit. This was a significant 6.2 degrees below the long-term mean of 18.6 degrees. Temperatures were mixed and varied wildly thought the month. December’s minimum temperature, minus 22 degrees Fahrenheit, was reported on the 21st. The month’s maximum temperature was 43 degrees and occurred December 28.

 

King Salmon experienced a greater-than-normal amount of precipitation in December, with a total of 2.05 inches. This precipitation was 67 percent above the long-term mean. Total monthly snowfall was 7 inches, 2.5 inches below normal. The average wind speed was 10.7 mph. The highest gust, 64 mph, occurred on the 8th. It blew from an easterly direction. The wind on December 8 created a new record wind speed for the day, breaking the 2005 record of 43 mph. 

 

In December, Kodiak was colder than normal, with a mean temperature of 28.8 degrees Fahrenheit. This was 2.4 degrees below the expected mean of 31.2 degrees Fahrenheit. Temperatures varied throughout the month, with a protracted cold spell from December 14 to 25. The maximum temperature for the month, 48 degrees, was observed on the 12th. That temperature was a new record high for the day, breaking the 1967 record of 47 degrees. The minimum temperature was a chilly 3 degrees reported on December 25 that tied the daily low record set in 1957. 

 

Precipitation was light in December at just 65 percent of normal, with a total of 5.64 inches. Snowfall was also light at just 62 percent of the normal of 13.8 inches. The average wind speed was 14.7 mph, while the highest wind gust occurred December 12 at 59 mph. That gust blew from a westerly direction.

 

Nome had a mean temperature for December of 3.3 degrees Fahrenheit. This temperature was a substantial 6.2 degrees below the normal value of 9.5 degrees. Temperatures stayed mostly below normal until the last five days of the month. December’s maximum temperature in Nome was reported at 34 degrees on the 29th and 30th. The minimum temperature, minus 30 degrees, was observed on the 18th and 19th.

 

Like the previous three months, December had below normal precipitation, with a total of 0.62 inches. This is just 57 percent of the normal amount of 1.08 inches. Snowfall totaled 14.7 inches, one percent above the normal. The average monthly wind speed was 6.5 mph; the maximum wind speed was 45 mph and occurred on the 30th. That gust blew from a northeasterly direction. 

 

This information consists of preliminary climatological data compiled by the Alaska Climate Research Center, Geophysical Institute, University of Alaska Fairbanks. For more information on weather and climatology, contact the center at 474-7885 or visit the center web site at http://akclimate.org. Please report any errors to webmaster@akclimate.org.