Alaska is having a rough summer. Following a July that was Alaska’s hottest month on record, erratic and unusual precipitation totals have caused downpours in some parts of the state and sparked fires and water restrictions in others.

14-day observed precipitation, Aug. 20

1 inch

or less

8 inches

or more

RUSSIA

Chukchi Sea

Bering

Sea

Nome

Prudhoe

Bay

Bethel

Alaska

Denali

Nat’l Park

Fairbanks

McKinley Fire

Swan Lake Fire

Anchorage

Yukon

Territory

Pacific

Ocean

Juneau

British

Columbia

300 MILES

Ketchikan

14-day observed precipitation, Aug. 20

Less than 1 inch

8 inches or more

RUSSIA

Nome

Prudhoe Bay

Bethel

Alaska

Denali

Nat’l Park

Fairbanks

McKinley Fire

Swan Lake Fire

Anchorage

Yukon

Territory

Pacific

Ocean

Juneau

British

Columbia

300 MILES

Ketchikan

14-day observed precipitation, Aug.20

Less than 1 inch

8 or more inches

RUSSIA

North

Nome

Fairbanks is on pace for one of the ten wettest months on record.

Bethel

Alaska

Denali Nat’l Park

Fairbanks

McKinley Fire

Anchorage

Swan Lake Fire

Pacific

Ocean

Anchorage has received

little precipitation and the air has been warm and smoky from nearby wildfires.

Yukon

Territory

Southeast Alaska, known as a temperate rainforest, has been below normal for rainfall in August, but Ketchikan just broke a 90-year record for daily rainfall yesterday with 4.85 inches of rain.

Juneau

British

Columbia

Ketchikan

300 MILES

August and September are typically the wettest months for Alaska. Northern Alaska, including Fairbanks, has been inundated with precipitation this month due to an atmospheric river event. Meanwhile in Southern Alaska, Anchorage received only trace amounts of rain in August, and only a quarter-inch of rain fell on Ketchikan, where water restrictions were being enforced until a heavy rain event Wednesday.

This lack of precipitation is also contributing to wildfires. Alaska’s fire season typically ends in July with the onset of August precipitation, but last weekend, dry conditions and high winds sparked a new fire, the McKinley Fire, just north of Anchorage along Parks Highway, destroying about 50 structures. These conditions also ramped up the already existing Swan Lake Fire in the Kenai Peninsula that was mostly contained, spreading smoke across Anchorage and a large swath of South-central Alaska. In Anchorage, air quality has been among the poorest observed in the United States this summer.

Wildfire areas burning on August 19

To Denali National Park

ALASKA

Detail

McKinley Fire

Willow

Smoke

Smoke

Anchorage

Whittier

Smoke

Swan Lake

Fire

Seward

Homer

50 MILES

Wildfire areas burning on August 19

To Denali National Park

ALASKA

Detail

McKinley Fire

Willow

Smoke

Smoke

Anchorage

Whittier

Smoke

Swan Lake

Fire

Seward

Homer

50 MILES

Wildfire areas burning on August 19

To Denali National Park

ALASKA

Detail

McKinley Fire

Willow

Smoke

Smoke

Anchorage

Whittier

Smoke

Swan Lake

Fire

Seward

Homer

50 MILES

Wildfire areas burning on August 19

To Denali National Park

ALASKA

Detail

McKinley Fire

Smoke

Willow

Smoke

Anchorage

Whittier

Smoke

Swan Lake

Fire

Seward

Smoke

Homer

50 MILES

“In most years, the season really ramps up around the first of June and reliably dies down by the first of August. Occasionally, the fire season lasts well into August,” said Brian Brettschneider, a researcher for the University of Alaska at Fairbanks at the International Arctic Research Center. While in the Lower 48 it can take months for vegetation to dry out enough to fuel fires, in Alaska, black spruce forests can be susceptible to fires after only a few days of dry conditions.

This is not a record fire year for Alaska, but it is a significant one with more than 2 million acres burned. The amount of acres burned due to wildfires throughout Alaska’s recorded fire history is variable, but the frequency of fire seasons where 2 million acres or more are burned has increased in recent years.

Acres burned in Alaska

6 million

4

11-year

rolling

avg.

2

0

1950

1960

1970

1980

1990

2000

2010

2019

Acres burned in Alaska

6 million

4

11-year

rolling

average

2

0

1950

1960

1970

1980

1990

2000

2010

2019

Acres burned in Alaska

6 million

4

11-year

rolling

average

2

0

1950

1960

1970

1980

1990

2000

2010

2019

Acres burned in Alaska

6 million

4

11-year

rolling

average

2

0

1950

1960

1970

1980

1990

2000

2010

2019

The setup for this extended fire season was exacerbated by unusually warm temperatures early in the summer. Anomalous warmth in the past year, as well as warmer-than-usual waters in the surrounding Bering, Chukchi, and Beaufort seas and the North Pacific Ocean fueled the warm and humid conditions experienced by Alaskans.

Sea surface temperature

anomaly, August 19

9˚F below normal

9˚F above normal

No

data

RUSSIA

Prudhoe

Bay

Bethel

Alaska

Anchorage

U.S.

CANADA

Yukon

Territory

Pacific

Ocean

Juneau

British

Columbia

Sea surface temperature anomaly, August 19

9˚F below normal

9˚F above normal

No

data

RUSSIA

Nome

Prudhoe Bay

Bethel

Alaska

U.S.

CANADA

Anchorage

Yukon

Territory

Pacific

Ocean

Juneau

British

Columbia

Sea surface temperature anomaly, August 19

9˚F below normal

9˚F above normal

RUSSIA

No data

Nome

Prudhoe Bay

Bethel

Alaska

U.S.

CANADA

Anchorage

Yukon

Territory

Pacific

Ocean

Juneau

British

Columbia

This “bathtub” of warm water surrounding Alaska helped contribute to higher-than-normal temperatures, especially overnight lows that trended higher than normal. In Anchorage, June and July were the warmest months ever recorded, with nighttime lows that rarely dropped below 50 degrees for most of the summer. In a city with buildings designed to keep warmth in, this has been problematic for residents.

Daily temperatures in Anchorage

On July 4, Anchorage set a record high of 90 degrees

90°F

Record

highs

80

70

60

Normal

temp.

range

50

Between June 21 and Aug. 18, the low temperature did not drop below 50 degrees, the second-longest stretch on record.

40

Record

lows

30

20

June 1

July 1

Aug. 1

Daily temperatures in Anchorage

On July 4, Anchorage set a record high of 90 degrees

90°F

Record

highs

80

70

60

Normal

temp.

range

50

Between June 21 and Aug. 18, the low temperature did not drop below 50 degrees, the second-longest stretch on record.

40

Record

lows

30

20

June 1

June 15

July 1

July 15

Aug. 1

Aug. 15

Daily temperatures in Anchorage

On July 4, Anchorage set a record high of 90 degrees

90°F

Record highs

80

70

60

Normal

temperature

range

50

Between June 21 and Aug. 18, the low temperature did not drop below 50 degrees, the second-longest stretch on record.

40

Record lows

30

20

June 1

June 15

July 1

July 15

August 1

August 15

Daily temperatures in Anchorage

On July 4, Anchorage set a record high of 90 degrees

90°F

Record highs

80

70

60

Normal

temperature

range

50

Between June 21 and Aug. 18, the low temperature did not drop below 50 degrees, the second-longest stretch on record.

40

Record lows

30

20

June 1

June 15

July 1

July 15

August 1

August 15

Anchorage has seen 14 nights dropping below 50 degrees this summer. The only other time the city saw so few was in 2016, when they had only 13 such nights. From 1952 to 2012, Anchorage had only five nights that failed to drop below 60 degrees. This summer, they have had 9 of those nights.

The warmer-than-usual waters are not expected to cool anytime soon, which will likely lead to a milder fall and early winter period. Alaskan firefighters who normally transition to firefighting in the Lower 48 in August continue to battle the fires back home.

About this story

Precipitation data from National Weather Service. Satellite imagery from NASA Worldview. Fire history data sourced from the Alaska Interagency Coordination Center and the Alaska Forestry Service. Sea surface temperature anomaly data from NOAA. Anchorage daily temperature data from National Weather Service.

Andrew Freedman and Tim Meko contributed to this report.