August 2012 Statewide Summary

Temperature

Below normal temperatures settled across most of Alaska for August. The most pronounced exception was Barrow with an astonishing positive deviation of 6.3°F. Arctic Alaska has shown the greatest warming over the last decades and this finding is in agreement with this trend. The other stations with positive deviations were: Big Delta (1.0°F), Fairbanks (0.2°F) and Valdez (0.2°F). All other sixteen first order stations exhibited below normal values. In this sense August mirrored June 2012. Generally, there was a gradient of the temperature deviations, from strong positive values in northern Alaska, to negative values in the south. The stations with the greatest negative deviations were: Homer (-2.2°F), Talkeetna (-1.9-°F), Gulkana (‑1.9°F), King Salmon (-1.6°F), and Kodiak (-1.5°F). A mean deviation of all twenty stations from the long-term mean could be calculated at ‑0.6°F, and this is the fourth month in a row with a mean below normal. See the table below for more details.

 

 

Station

Temperature

Observed
(°F)

Normal
(°F)

Delta
(°F)

Anchorage

55.9

56.7

-0.8

Annette

57.7

58.9

-1.2

Barrow

45.3

39.0

6.3

Bethel

52.3

53.5

-1.2

Bettles

52.2

52.5

-0.3

Big Delta

56.1

54.8

1.3

Cold Bay

51.2

52.1

-0.9

Fairbanks

56.3

56.1

0.2

Gulkana

51.6

53.5

-1.9

Homer

51.7

53.9

-2.2

Juneau

54.6

55.9

-1.3

King Salmon

53.0

54.6

-1.6

Kodiak

53.7

55.2

-1.5

Kotzebue

51.1

51.7

-0.6

McGrath

54.4

54.6

-0.2

Nome

49.2

50.1

-0.9

St. Paul Island

47.6

48.8

-1.2

Talkeetna

54.8

56.7

-1.9

Valdez

53.9

53.7

0.2

Yakutat

52.5

53.8

-1.3

 

Temperature records were a mix of both high and low events, scattered along the coast from Barrow to Valdez. Valdez had a record low on the 22nd and a record high on the 29th. Barrow set two new daily highs temperatures, and the old record on the 19th was originally set way back in 1923, and then tied in 1954. In another indication of the extreme warmth in Barrow for August 2012, six new daily high minimum temperature records were set between the 14th and 22nd (see the included figure).

 

 

Temperature Records

Date

Station

Element

New
Record

Old
Record

Year of
old Record

08/03/12

Cold Bay

Low Temperature

33

39

1975

08/13/12

St. Paul

High Temperature

64

57

1989

08/14/12

St. Paul

High Temperature

63

59

2005

08/18/12

Kodiak

Low Temperature

41

42

1985

08/19/12

Barrow

High Temperature

66

63

1954

08/22/12

Valdez

Low Temperature

42

42

2005

08/22/12

Barrow

High Temperature

63

63

1972

08/24/12

Cold Bay

Low Temperature

38

39

1988

08/29/12

Valdez

High Temperature

69

69

1977

 

Daily temperature ranges and precipitation for Barrow for August 2012. Note the two record high temperature events. In addition, notice the very warm daily low temperatures values starting on the 14th. A noteworthy total of six new high minimum records were set between the 14th and 22nd of the month (not marked).

 

 

Precipitation

Like temperature, precipitation was mixed with six of the first order stations reporting above normal totals, and the rest reporting below normal totals. The greatest positive deviations of normal, expressed in percentages, were found along the northern, northwestern parts of Alaska, and at Juneau: Kotzebue (100%), Nome (66%), and Juneau (32%). On the other side of the spectrum were the below normal stations of: Yakutat, with only 50% of the expected value, Gulkana (53%), Cold Bay (56%) and Annette (59%). With the preponderance of stations reporting below average precipitation, it comes as no surprise the mean precipitation deviation for all stations is 7% below normal. Barrow was the only first order station to register snowfall in July with just trace amounts measured on six days, not reaching the normal total for the month of 0.9", an expected result given the extremely warm month experienced there. As with the temperature, the precipitation deviations for the twenty first order stations are given in the table below:

 

Station

Precipitation

Observed
(in)

Normal
(in)

Delta
(in)

(%)

Delta
(%)

Anchorage

2.05

3.25

-1.20

63%

-37%

Annette

4.09

6.96

-2.87

59%

-41%

Barrow

1.09

1.05

0.04

104%

4%

Bethel

3.09

3.25

-0.16

95%

-5%

Bettles

3.12

2.64

0.48

118%

18%

Big Delta

1.05

1.89

-0.84

56%

-44%

Cold Bay

2.06

3.68

-1.62

56%

-44%

Fairbanks

1.45

1.88

-0.43

77%

-23%

Gulkana

0.95

1.80

-0.85

53%

-47%

Homer

1.89

2.34

-0.45

81%

-19%

Juneau

7.59

5.73

1.86

132%

32%

King Salmon

2.64

2.95

-0.31

89%

-11%

Kodiak

3.18

4.56

-1.38

70%

-30%

Kotzebue

4.36

2.18

2.18

200%

100%

McGrath

3.12

2.80

0.32

111%

11%

Nome

5.35

3.22

2.13

166%

66%

St. Paul Island

2.95

3.07

-0.12

96%

-4%

Talkeetna

4.32

5.11

-0.79

85%

-15%

Valdez

5.64

7.30

-1.66

77%

-23%

Yakutat

7.02

14.07

-7.05

50%

-50%

 

 

There were a limited number precipitation records for August, backing up the light rainfall experienced for most stations. The month started off with a number of events set in the Southeast on the 8th as a cyclonic system moved across the region. Most of the rest of the events were located in the western part of the state around the Bering Sea and Bering Strait areas, with the exception of Bettles on the 30th. The two record events in Kotzebue helped drive its twice-normal precipitation for August.

 

 

Precipitation Records

Date

Station

Element

New
Record

Old
Record

Year of
old Record

08/08/12

Juneau

Precipitation

1.21

1.18

2002

08/08/12

Petersburg

Precipitation

1.42

1.36

2002

08/08/12

Gustavus

Precipitation

0.92

0.43

1988

08/19/16

Nome

Precipitation

1.06

0.95

1973

08/21/12

Kotzebue

Precipitation

0.95

0.90

1955

08/28/12

St. Paul

Precipitation

0.99

0.56

1981

08/28/12

Juneau

Precipitation

1.28

0.76

1988

08/30/12

Bettles

Precipitation

0.75

0.70

1988

08/31/12

Kotzebue

Precipitation

0.41

0.40

1964

 

The month started off with a travel advisory being issued on the 7th for the Dalton Highway as an early season snowfall of four to five inches in Atigun Pass hampered travel. Flood watches were issued in mid month for northwest Alaska as a once in 100-year rainfall event struck the region. Gauges in the region were recording four to six inches total of precipitation over several days starting on the 13th; when an unusual low-pressure front stalled over the Chukchi Sea and poured rain into the region for most of a week. Kivalina bore the brunt of the storm as flooding knocked out the water supply, and then spread waste as the flooding hit the community landfill. The lack of water delayed the opening of school.

 

Also at the beginning of the month it looked like the fire season was all but ended, with a very small area consumed of just over 200,000 acres due to low lightning strike counts and persistently cool weather. Lighting strike count was lowest since 2003. However, nice weather in the Interior starting about the 10th encouraged the Dry Creek fire (ignited on June 23rd by a lightening strike and located eighteen miles south of North Pole) to spread and bring smoke to the Fairbanks area on the 20th and for the next several days. Air quality alerts were in place for most of the week. A steady rain over the weekend of the 25th and 26th dampened the fire. The rains also generated flood advisory for small streams near Denali National Park. By the end of August the Dry Creek fire was in the process of burning itself out.

 

 

This information consists of preliminary climatological data compiled by the Alaska Climate Research Center, Geophysical Institute, University of Alaska Fairbanks. This summary is based on the 20 first order stations in Alaska operated by the National Weather Service. Extreme events of other stations are also mentioned. It should be noted that the new climate normals for the time period of 1981-2010 are applied for the calculations of the deviations, and they can be slightly different from the old normals (1971-2000), which were in use up until end of July 2011.