Fairbanks Annual Review 2013

Fairbanks Annual Weather Review

2013

The temperature of Fairbanks was somewhat above normal (0.4°F) for 2013 at a mean temperature of 28.1°F. The highest temperature of 92°F was observed on the 25^th and 26^th of June 2013, close to the summer solstice with over 21.5 hours of sunlight. There were 30 days with temperatures above 80°F, surpassing the long-term mean (1949-present) of twelve days by more than twofold. The lowest temperature of the year was ‑48°F occurring on the 27^th January, and there were only six days with minima below ‑40°F; the long term mean is eleven days. With other words, Fairbanks had more hot days than normal in summer and fewer real cold days than normal in winter when compared to the long term, which might be expected by global warming. However these deviations are hardly visible in the mean annual temperature, which is close to normal.

Looking at the monthly data, which are presented in Table 1, it can be clearly seen that on a monthly basis, very large variations were observed. The greatest departure from normal was observed in April, which was an astonishing 14.5°F below the long-term mean of 32.5°F. It was the third coldest April on record for more than 100 years. The lowest temperature for the month was a chilly -21°F on the 11^th. That -21°F was a new daily record low, breaking the old record of -17°F set in 1955. Another record low was set the next day with -15°F and broke the 1936 record of -12°F. Then on the 28^th the temperature bottomed out at 2°F shattering the 8°F record from way back in 1924. With the exception of the first three days of the month, the temperatures stayed significantly below normal for the rest of the month. 

On the other side of the coin, there was October with a temperature at 44.0°F, much too warm with a deviation of 11.9°F above normal. The warmest temperature for the month was recorded at 57°F on the 18^th and 19^th. The max of 51°F on the 28^th was a new record, breaking the old high of 44°F from 1959. Overall, this was the third warmest October in 109 years.

Further, the summer season should be mentioned, with all three months having an above normal temperature, with June leading the positive deviations (see Table 1). This brought also many sunny and warm days with on two occasions temperatures above 90°F, unusual for Interior Alaska. In addition, the minimum temperature of 70°F on the 25^th was the warmest minimum daily temperature on record for any day in Fairbanks. For Fairbanks, with its long-term climate record, it was the second warmest summer (deviation +3.8°F); only 2004 reported a higher summer temperature. The summer of 2004 was unpleasant insofar that smoke from large wildfires affected strongly the air quality. More than 6 million acres burned. However, while 2013 had a similar temperature regime, the region was much less affected by smoky air. The area burned was above normal (1.3 million acres), the deviation from the long-term mean, some 1 million acres, was not substantial. In Figure 2 the annual course of the temperature and the deviations from the normal are presented, and details for other months can be obtained from this graph.

Precipitation in 2013 was 10.65", very close to the expected value of 10.81".  The annual course over the year, both, for the long-term mean and 2013 are presented value in Figure 3 (cumulative daily precipitation).  It can be seen from the figure, that sum of the precipitation for the first five months was slightly above normal, thereafter most of the summer was too dry, but late August/early September and November reported above normal values, so that at the end of the year we came very close to the expected value. The snowfall of the year was at 72.0", 12% above the normal value of 63.6". Monthly precipitation data can be seen in Table 2.

Some other interesting climatological facts for this year are the following:

• The last frost in spring occurred on the 21st of May, the first frost in fall was observed on 15th September, resulting in a growing season length of 117 days, close to normal.
• Green-up occurred on the 26th of May, which is later than normal.
• Mean annual wind speed was 4.2 mph, with lower values in winter, when the semi-permanent inversion decouples the surface conditions from the upper circulation.
• The snowfall of the year was at 72.0”, 12% above the normal value of 63.6”.
• April was the 8th snowiest on record reaching 25” on the 9th.
• On 13/14 November, a strong storm blowing from the Bering Sea brought warm temperatures and rain to Fairbanks, making driving conditions difficult. Schools were closed. A wind gust of 55 mph was measured at the airport. Falling trees caused widespread power outages.