October 2012 Statewide Summary

Temperature

Colder than normal temperatures dominated much of the state this October; this was especially true in the latter half of the month. Gulkana had the largest negative deviation with -5.2°F. The next three stations with large negative deviations are located in the Southeast: Yakutat (-4.0°F), Juneau (-3.9°F) and Annette (-2.5°F). Stations with positive deviations were located in the northern and western part of the state with Barrow topping out the stations with a positive deviation of an astounding 10.3°F. Kotzebue also had a significant departure with 4.4°F. In general, there was a strong gradient from highly positive values in Northeast Alaska to negative values in the Southeast. A mean deviation of all twenty stations from the long-term mean could be calculated at ‑0.5°F (0.1°F higher deviation than August and September) and this is the sixth 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

33.2

34.8

-1.6

Annette

44.2

46.7

-2.5

Barrow

27.5

17.2

10.3

Bethel

31.4

30.3

1.1

Bettles

18.6

18.9

-0.3

Big Delta

21.9

24.1

-2.2

Cold Bay

40.5

40.4

0.1

Fairbanks

22.5

24.2

-1.7

Gulkana

21.4

26.6

-5.2

Homer

36.8

38.1

-1.3

Juneau

38.5

42.4

-3.9

King Salmon

31.3

33.5

-2.2

Kodiak

39.5

40.5

-1.0

Kotzebue

28.7

24.3

4.4

McGrath

26.3

25.1

1.2

Nome

30.6

28.7

1.9

St. Paul Island

38.5

38.6

-0.1

Talkeetna

32.1

33.2

-1.1

Valdez

37.4

38.4

-1.0

Yakutat

37.0

41.0

-4.0

 

 

Daily temperature ranges and precipitation for Ketchikan for October 2012. Note the three record cold events during the protracted cold spell at the end of the month.

 

New temperature records started out the month with a number of high events, scattered across the state from Annette to St. Paul to Barrow, exemplifying the warm start to the month. However, after the 22nd all new temperature records were cold, and occurred in the Southeast as a strong offshore wind brought cold air in from the continent, and kept the relative warm air from the ocean away. Some of these records had stood for considerable amounts of time, as in the case on the 22nd in Ketchikan where the previous record had been in place since 1919.

 


 

Temperature Records

Date

Station

Element

New
Record

Old
Record

Year of
old Record

10/02/16

Valdez

Low Temperature

27

28

1994

10/06/16

Big Delta

High Temperature

59

57

1952

10/06/16

Barrow

High Temperature

41

39

1925

10/07/16

Annette

High Temperature

68

66

1969

10/07/16

Barrow

High Temperature

38

38

1992

10/08/16

Annette

High Temperature

69

64

1964

10/08/16

King Salmon

High Temperature

61

59

1925

10/09/16

Annette

High Temperature

63

62

2003

10/10/16

Cold Bay

High Temperature

60

57

1986

10/11/16

Cold Bay

High Temperature

57

52

2002

10/12/16

King Salmon

High Temperature

56

56

2009

10/22/16

St. Paul

High Temperature

47

47

1989

10/22/16

Sitka

Low Temperature

30

31

1991

10/23/16

Ketchikan

Low Temperature

28

29

1919

10/23/16

Sitka

Low Temperature

29

29

1956

10/24/16

Annette

Low Temperature

32

32

2004

10/25/16

Ketchikan

Low Temperature

28

28

1991

10/25/16

Annette

Low Temperature

28

31

1991

10/26/16

Sitka Observatory

Low Temperature

26

28

1969

10/27/16

Annette

Low Temperature

26

27

1991

10/27/16

Haines Airport

Low Temperature

21

25

1984

10/27/16

Craig

Low Temperature

28

32

2004

10/28/16

Yakutat

Low Temperature

12

15

1982

10/28/16

Gustavus

Low Temperature

10

11

1990

10/28/16

Pelican

Low Temperature

22

24

1971

10/28/16

Annette

Low Temperature

25

25

1971

10/29/16

Yakutat

Low Temperature

14

18

1982

10/29/16

Gustavus

Low Temperature

9

11

1984

10/29/16

Pelican

Low Temperature

23

23

1984

10/29/16

Sitka

Low Temperature

24

26

1984

10/29/16

Annex Creek

Low Temperature

22

23

1984

10/29/16

Craig

Low Temperature

25

28

1991

10/30/16

Ketchikan

Low Temperature

25

25

1991

10/30/16

Ketchikan

Low Temperature

25

25

1991

10/30/16

Petersburg

Low Temperature

15

18

1984

10/30/16

Craig

Low Temperature

24

28

1950

10/31/16

Craig

Low Temperature

23

28

2003

10/31/16

Hollis

Low Temperature

21

26

2006

10/31/16

Skagway Power

Low Temperature

20

20

2002

 

The cold spell at the end of the month in the Southeast resulted in a number of new record low mean monthly temperatures. They are summarized in the table below.

 

 

Monthly Low Temperature Records

Station

New
Record

Old
Record

Difference

Year of
old Record

Haines Airport

38.0

38.7

-0.7

1950

Gustavus

37.5

38.8

-1.3

1991

Hoonah

40.1

41.5

-1.4

2008

Craig

44.2

45.5

-1.3

2007

Klawock

42.3

44.6

-2.3

2004

 

 

Precipitation

For the state as a whole, precipitation was near normal and only seven of the stations reported heavier than normal totals. The station with the highest deviation was Barrow at 139% above normal. Fairbanks also saw notably high levels at 66% greater than expected. Stations reporting significantly less the normal precipitation were located in the Southeast: Yakutat with just 31% of the expected value, then: Annette (39%) and Juneau (41%). Exemplifying the dry cold trend at the end of October in the Southeast was Juneau with eleven days in a row at the end of the month without any precipitation. On only 12 days was there measurable precipitation; normally there are twenty-four days in October. Even with the preponderance of stations reporting less than normal precipitation, the mean precipitation deviation for all stations was merely a scant 1% below normal.

 

With the help of the cold spell experience in the Southeastern portion of the state, Yakutat was the first order station to register the most snowfall in October with a total of 18.1", 15.6" higher than the normal amount. King Salmon similarly had a snowy month with a total of 11.6", 8.8" higher than expected. Barrow also saw heavy snow with 12.8", 3.7" above normal. Overall, snow depth levels were at normal, or below normal where reported. 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

2.70

2.03

0.67

133%

33%

Annette

5.44

13.92

-8.48

39%

-61%

Barrow

0.98

0.41

0.57

239%

139%

Bethel

2.19

1.65

0.54

133%

33%

Bettles

0.82

1.04

-0.22

79%

-21%

Big Delta

0.78

0.80

-0.02

98%

-3%

Cold Bay

4.72

4.76

-0.04

99%

-1%

Fairbanks

1.38

0.83

0.55

166%

66%

Gulkana

0.77

1.01

-0.24

76%

-24%

Homer

2.06

2.57

-0.51

80%

-20%

Juneau

3.50

8.63

-5.13

41%

-59%

King Salmon

1.86

2.08

-0.22

89%

-11%

Kodiak

4.71

8.26

-3.55

57%

-43%

Kotzebue

1.12

1.01

0.11

111%

11%

McGrath

1.80

1.44

0.36

125%

25%

Nome

1.36

1.61

-0.25

84%

-16%

St. Paul Island

3.85

3.11

0.74

124%

24%

Talkeetna

2.72

2.90

-0.18

94%

-6%

Valdez

7.33

8.24

-0.91

89%

-11%

Yakutat

6.85

21.98

-15.13

31%

-69%

 

With the exception of the 14th when heavy rain set new precipitation records for Juneau and Annex Creek, new daily record rainfall records were absent from the Southeast due to the cold dry offshore flow that dominated the last part of the month. The cold temperatures generated two tied trace snowfall records for Juneau on the 17th and 18th. While King Salmon did have a dryer than normal month overall, there was one new precipitation record and two new snowfall records set. Valdez also set two new rainfall records as well as a new snowfall record.

 

 

Precipitation Records

Date

Station

Element

New
Record

Old
Record

Year of
old Record

10/04/16

St. Paul

Precipitation

1.09

1.00

2001

10/05/16

Kotzebue

Precipitation

0.42

0.41

1956

10/06/16

Valdez

Precipitation

2.50

2.42

1979

10/07/16

Valdez

Precipitation

2.44

1.49

2000

10/08/16

Fairbanks

Precipitation

0.21

0.21

1989

10/08/16

Bethel

Precipitation

0.88

0.53

1970

10/08/16

King Salmon

Precipitation

0.86

0.71

1949

10/09/16

McGrath

Precipitation

0.66

0.66

1985

10/09/16

Fairbanks

Precipitation

0.55

0.28

1974

10/14/16

Valdez

Snowfall

1.60

1.00

2008

10/14/16

King Salmon

Snowfall

3.90

1.50

1966

10/14/16

Juneau

Precipitation

1.65

1.46

1945

10/14/16

Annex Creek

Precipitation

2.67

2.35

1961

10/15/16

King Salmon

Snowfall

7.20

3.00

1956

10/17/16

Juneau

Snowfall

0.00

0.00

1996

10/18/16

Juneau

Snowfall

0.00

0.00

1996

 

The clear, cold weather experienced at the end of the month in the Southeast generated a number of new record low mean monthly temperatures, as noted above. The cold and dry conditions also resulted in new record low monthly precipitation records being set across the region. These records are tabulated in the following table.

 

 

Monthly Low Precipitation Records

Station

New
Record

Old
Record

Difference

Year of
old Record

Annette

5.44

7.03

-1.59

2002

Gustavus

3.41

5.53

-2.12

1999

Haines Airport

2.05

3.16

-1.11

1950

Hoonah

4.20

7.41

-3.21

2009

Klawock

5.82

8.19

-2.37

2002

Pelican

6.77

10.08

-3.31

1971

Petersburg

6.12

8.23

-2.11

1950

Sitka

5.92

6.30

-0.38

1950

Snettisham Power

10.28

15.53

-5.25

2003

 

Fairbanks saw the first ice float down the Chena River on October 12th, followed by the first measurable snowfall on the 14th, almost two weeks later than normal, as the average date of first measurable snowfall is October 1st. The snowing continued, and on the 14th a snowstorm made Atigun Pass treacherous to motor traffic and a travel advisories were instituted until the 19th. Travel advisories were also issued for parts of the Richardson Highway due to snow. Cold temperatures settled across most of the state for the second half of the month, and Fairbanks saw its first below zero temperature (-5°F) on the 22nd. The Dalton Highway received another winter travel advisory due to blowing and drifting snow on the 31st. Also on the 31st, Kodiak experienced some interesting smog-like haze. A lack of snow and strong winds (35 to 40 mph) had driven ash from the 1912 eruption of the Norarupta volcano on the Alaska Peninsula across the Shelikof Strait to settle across parts of the island.

 

 

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.