September 2016 Statewide Summary

Alaska Statewide Climate Summary

September 2016

 

Temperature

 

September 2016 marks the twelfth month in a row with statewide mean temperatures above normal. The monthly mean temperature of all First Order Stations was 47.8°F, 2.2°F above the normal of 45.6°F. This is 3.5°F above the September 2015 mean of 44.3°F. Calculating the mean daily temperatures of the First Order Stations, 28 days of the month were above the 30-year normal, with two days (25th and 26th) below normal (see Figure). The peak positive deviation for the month occurred on the 21st at 5.0°F. Monthly mean temperatures (see table) were above normal for 18 of the 19 First Order Stations. The only station with a below normal mean monthly temperature was Bettles with -0.7°F below its normal of 40.6°F. St. Paul Island had the greatest positive deviation of 4.6°F above its normal of 45.3°F.

 

Station

Temperature

Observed
(°F)

Normal
(°F)

Delta
(°F)

Anchorage

51.7

48.6

3.1

Annette

55.5

53.8

1.7

Barrow

34.5

32.1

2.4

Bethel

47.9

45.6

2.3

Bettles

39.9

40.6

-0.7

Cold Bay

51.1

48.1

3.0

Delta Junction

46.2

43.9

2.3

Fairbanks

46.2

44.9

1.3

Gulkana

46.1

43.3

2.8

Homer

51.2

48.1

3.1

Juneau

51.2

50.0

1.2

King Salmon

51.3

47.6

3.7

Kodiak

51.7

49.4

2.3

Kotzebue

44.1

42.3

1.8

McGrath

46.6

44.6

2.0

Nome

43.8

42.8

1.0

St. Paul Island

49.9

45.3

4.6

Talkeetna

48.7

47.5

1.2

Yakutat

50.1

48.4

1.7

 

 

The highest daily maximum temperature of the First Order Stations for September was 75°F reported at King Salmon on the 1st. Annette held the spot for the highest mean temperature for the month at 55.5°F. The lowest temperature of 16°F was observed at Gulkana on the 30th. Barrow reported the lowest September mean monthly temperature with a value of 34.5°F.

 

 

Daily mean temperature deviation from the normal temperature for the mean of the First Order Stations for September 2016.

 

There were a fair number of daily temperature record events and all were high events. Most of the events occurred during the first few days at the start of the month during the very nice weather across the southern coastal areas of the state. St. Paul had eight high events; St. Paul also had nine record high minimum temperature events during September (not shown).

 

 

 

Temperature Records

Date

Station

Element

New
Record

Old
Record

Year of
old Record

09/01/16

Bethel

High Temperature

73

67

2008

09/01/16

King Salmon

High Temperature

75

70

2013

09/01/16

Kodiak

High Temperature

70

67

2013

09/01/16

St. Paul

High Temperature

56

56

2014

09/01/16

Yakutat

High Temperature

67

67

1981

09/02/16

Anchorage

High Temperature

71

70

1963

09/02/16

Bethel

High Temperature

74

69

1975

09/02/16

Cold Bay

High Temperature

62

62

2015

09/02/16

King Salmon

High Temperature

72

70

1963

09/02/16

Yakutat

High Temperature

68

68

1996

09/04/16

Cold Bay

High Temperature

62

62

1985

09/04/16

St. Paul

High Temperature

57

57

2014

09/05/16

St. Paul

High Temperature

59

58

2014

09/10/16

Cold Bay

High Temperature

61

61

1989

09/14/16

St. Paul

High Temperature

57

56

2014

09/15/16

St. Paul

High Temperature

54

54

2014

09/26/16

St. Paul

High Temperature

54

54

2014

09/29/16

Barrow

High Temperature

43

43

1989

09/29/16

St. Paul

High Temperature

52

50

2014

09/30/16

Barrow

High Temperature

48

41

1955

09/30/16

St. Paul

High Temperature

53

53

1978

 

It was the warmest September on record for Cold Bay with 51.3°F, 0.5°F above the old 2014 record. St. Paul also set a new record with 49.9°F, breaking the 2014 record of 49.5°F. Finally, Dutch Harbor also set a new record with 53.0°F, 0.5°F above the old 2010 record. This September was the fourth warmest for Homer, while it was the fifth warmest September for Anchorage. For the year ending September 2016 Juneau had had all 12 consecutive months with above average monthly mean temperatures.

 

 

Precipitation

 

September's precipitation was significantly above normal, with the overall precipitation calculated as 26% below the average; this calculation was based on the mean of the deviations in percentage of the First Order Stations. Thirteen of the First Order Stations and 17 days of the month reported above normal values. There were no days during the month without any measureable precipitation at all of the 19 First Order Stations. This is slightly drier than September 2015, which reported a positive deviation of 28%. The greatest daily deviation of 259% occurred on the 22nd. The leading station with a greater than normal monthly precipitation amount was Bettles with 5.34", or 280% of normal. This represents the wettest September on record for Bettles, breaking the old record of 4.80" from 2002. This September was the fourth wettest September on record for Juneau and fifth wettest for McGrath. Gulkana was the relatively driest station at just 56% of normal precipitation observed.

 

Station

Precipitation

Observed
(in)

Normal
(in)

Delta
(in)

Delta
(%)

(%)

Anchorage

2.35

2.99

-0.64

-21%

79%

Annette

10.23

9.79

0.44

4%

104%

Barrow

0.77

0.72

0.05

7%

107%

Bethel

3.17

2.75

0.42

15%

115%

Bettles

5.34

1.91

3.43

180%

280%

Cold Bay

5.87

4.73

1.14

24%

124%

Delta Junction

0.73

1.03

-0.30

-29%

71%

Fairbanks

2.08

1.10

0.98

89%

189%

Gulkana

0.89

1.58

-0.69

-44%

56%

Homer

4.86

3.31

1.55

47%

147%

Juneau

11.64

8.64

3.00

35%

135%

King Salmon

4.84

3.19

1.65

52%

152%

Kodiak

4.99

7.35

-2.36

-32%

68%

Kotzebue

2.02

1.58

0.44

28%

128%

McGrath

5.08

2.49

2.59

104%

204%

Nome

2.29

2.45

-0.16

-7%

93%

St. Paul Island

4.45

2.99

1.46

49%

149%

Talkeetna

5.22

4.32

0.90

21%

121%

Yakutat

16.10

21.11

-5.01

-24%

76%

 

Daily mean precipitation deviation from the normal for the First Order Stations for September 2016.

 

 

September's highest monthly precipitation total reported for a First Order Station was 16.10" at Yakutat, and Yakutat also reported the highest daily total of 3.74" on the 12th, a new daily record.

 

The table below lists the limited number of daily precipitation records set in September.

 

 

Precipitation Records

Date

Station

Element

New
Record

Old
Record

Year of
old Record

09/06/16

Auke Bay

Precipitation

1.80

1.35

1981

09/06/16

Juneau

Precipitation

1.28

1.18

1981

09/09/16

Juneau

Precipitation

2.96

1.34

1995

09/11/16

McGrath

Precipitation

1.08

0.65

1961

09/12/16

Yakutat

Precipitation

3.74

3.61

1990

09/15/16

Sitka

Precipitation

2.44

2.18

1985

09/20/16

Kodiak

Precipitation

1.95

1.59

1990

09/29/16

Barrow

Precipitation

0.27

0.17

1958

 

 

 

Newsworthy Events

 

September 1st saw frost warnings issued for areas of the Southcentral. Then on the 2nd smokejumpers were sent to fight a wildfire near Koyuk. Snowfall in the Eastern Brooks Range on the 7th caused very difficult driving conditions along the Dalton Highway. Widespread frost warnings for the next day were issued for the Fairbanks area on the 7th. The Fairbanks Airport reported a low of 30°F on the 8th, resulting in a growing season of 125 days long for Fairbanks for 2016. Frost was reported across the Fairbanks North Star Borough, and widespread frost warnings were again issued for the 9th. More snow was reported in the Brooks Range during the weekend of the 9th due to a second cold front moving down out of the Arctic. At the same time the remnants of hurricane Lester impacted the Panhandle area with heavy rains and high winds forecasted for the Central Panhandle. Sitka reported wind speeds up to 40 mph. Cape Spence reported 62 mph, while 61 mph was reported from Cape Decision.

 

On the 10th, high wind warnings were issued for South Central and Interior areas for the weekend of the 10th up to Monday the 12th for gusts up to 70 mph in passes and up to 85 mph along the Turnagain Aram area due to a low-pressure system moving east from the Aleutian area. A gust of 81 mph was reported on the hillside in Anchorage on the 11th. Minor property damage was reported out to Palmer. A gust of 75 mph was reported southeast of Fairbanks on the 12th. Power outages affected thousands in the Anchorage area. Seward received more than 4.6" of rain during the storm, and the flood advisories were issued for the Seward River, while some water was reported on the airport runway. The storm moved east to Southeastern areas on the 12th with gusts up t 67 mph reported at Cape Spencer, 62 mph at Skagway Airport, and 45 at downtown Juneau. Also on the 12th storm warnings were issued for the North Slope and high winds warning and snow for the Brooks Range. Hazardous driving conditions were reported along the Dalton Highway on the 15th.

 

A mudslide temporarily covered the tracks of the Alaska Railroad on the 14th. The mudslide came down when a fright train was passing, but did not damage the train or the tracks. Snow up to 2" was forecast on the Denali Park road on the 17th.

 

ICEPICK:gi:Monthly Summaries:2016:09:Figure 3.png

This NWS satellite image shows the storm moving east that impacted the Southcentral and Interior areas of Alaska on the 21st.

 

A new round of high wind warnings were issued for Southcentral and Interior areas on the 19th for another Bering Sea storm moving east on the 20th and 21st with gusts possibly up to 100 mph along Turnagain Arm. Gusts over 80 mph were reported at Delta Junction on the 21st. The Anchorage hillside reported gusts up to 82 mph, while Upper DeArmoun Road reported a gust at 103 mph, and Fairweather Grounds buoy reported sustain gust over 45 mph. Power outages extended from Kasilof to Anchorage to Fairbanks to Delta Junction. Minor property damage was reported. A few cargo planes were diverted from Anchorage to Fairbanks, while water again moved over the Seward Airport runway. High wind warnings continued in the area on the next day. The storm also generated more than 100 lightning strikes in a couple hours in the northern gull coast on the 23rd.

 

Difficult driving's conditions due to blowing snow impacted motorists on the Steese Highway on the 23rd. On the 26th the first snow was reported in Delta Junction. The next day the first snow hit the Fairbanks area. As the month closed out, hazardous driving conditions were reported along the Dalton Highway, while a new low-pressure system in the Bering Sea resulted in high winds reported in the area. Gusts up to 78 mph were recorded at Cape Newenham, 71 mph at Cold Bay, 67 mph at King Coe and 69 mph at Akun Airport.

 

 

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 907-474-7885 or visit the center web site at http://akclimate.org. Please report any errors to webmaster@akclimate.org. This summary is based on the 19 First Order Stations in Alaska operated by the National Weather Service. Extreme events of other stations are also mentioned.