Winter 2017-2018 Outlook - Wetter than normal for much of the Northland

Winter 2017-2018 Outlook for the Northland

(meteorological winter defined as December, January, and February)

NOAA Climate Prediction Center United States winter 2017-2018 Outlook
Temperature Outlook	Precipitation Outlook

For this upcoming winter the Climate Prediction Center (CPC) temperature and precipitation forecast generally reflects a typical La Niña pattern: Warmer and drier than normal conditions across the southern United States, with warmer than normal conditions expected across the Mid-Atlantic and Northeastern United States Cooler than normal conditions from the Pacific Northwest east to parts of the Upper Mississippi River Valley, with wetter than normal conditions across the northern Rockies, Great Lakes and Ohio River Valley Wetter than normal conditions does not necessarily mean that it will snowier than normal. Equal chances of above, below, and near normal temperatures are forecast for the Northland Confidence is highest for a warm and dry winter across the southern United States

Looking back at the 2016-2017 winter

Temperature Anomalies

Precipitation Anomalies

Last winter we had a weak La Niña. This brought the Northland, and the majority of the lower 48, temperatures that were above normal. Much of the Northland saw above normal precipitation.

Observed Values for the Winter of 2016-2017
Location	Average Temperature (°F)	Precipitation (in)	Snowfall (in)
Duluth, MN	18.1	5.03	50.9
International Falls, MN	13.0	4.94	54.9
Brainerd, MN	17.2	3.62	28.6
Hibbing, MN	13.1	-	-
Ashland, WI	20.9	-	-

Normal Values for the Winter (The seasonal climate normals are from a 30 year period defined by the Climate Prediction Center as 1981-2010)
Location	Average Temperature (°F)	Precipitation (in)	Snowfall (in)
Duluth, MN	13.3	2.98	49.5
International Falls, MN	8.1	2.00	40.8
Brainerd, MN	14.4	2.25	26.2
Hibbing, MN	10.0	-	-
Ashland, WI	16.5	-	-

Duluth saw its 14th warmest winter season on record last year with an average temperature of 18.1 degrees, which was 4.6 degrees above the normal of 13.3 degrees. A total of 5.03 inches of precipitation was recorded for the season, which was 2.05 inches above the normal of 2.98 inches. This made it the 13th wettest winter season on record for Duluth. 50.9 inches of snow fell through the season, which was 1.4 inches above the normal of 49.5 inches.

International Falls saw its 11th warmest winter season on record last year with an average temperature of 13.0 degrees, which was 4.9 degrees above the normal of 8.1 degrees. A total of 4.94 inches of precipitation was recorded for the season, which was 2.94 inches above the normal of 2.00 inches. This made it the wettest winter season on record for International Falls. 54.9 inches of snow fell for the season, which was 14.1 inches above the normal of 40.8 inches. This made it the 11th snowiest winter season on record.

Brainerd saw its 11th warmest winter season on record last year with an average temperature of 17.0 degrees, which was 2.6 degrees above the normal of 14.4 degrees. A total of 3.62 inches of precipitation was recorded for the season, which was 1.37 inches above the normal of 2.25 inches. This made it the 5th wettest winter season on record for Brainerd. 28.6 inches of snow fell through the season, which was 2.4 inches above the normal of 26.2 inches.

Hibbing saw its 17th warmest winter season on record last year with an average temperature of 13.0 degrees, which was 3.0 degrees above the normal of 10.0 degrees.

Ashland saw its 9th warmest winter season on record last year with an average temperature of 20.7 degrees, which was 4.2 degrees above the normal of 16.5 degrees.

Current El Niño/La Niña Conditions

Current and Forecast El Nino/La Nina Conditions:

ENSO-Neutral conditions are currently present. Weak La Niña conditions favored to develop this fall and continue through the winter
A La Niña Watch is still in effect from the Climate Prediction Center

Typical wintertime La Niña Impacts

In general, there tends to be a weakening of the jet stream
This results in ridging developing across the northeast Pacific Ocean, which sends the Polar jet stream into Alaska
As the Polar jet stream passes through Alaska it captures arctic air before flowing southeastward into the Pacific Northwest and Northern Plains
Locally this pattern typically brings a higher frequency of arctic air outbreaks during the winter, and due to a more active storm track across the Northern Plains, a tendency for more frequent snowfalls

Past weak La Niña winters

Composite Temperature Anomalies

Composite Precipitation Anomalies

There have been 12 winters since 1950 where weak La Niña conditions have been observed. The images above are a composite of all the weak La Niña winter seasons.

The last 12 weak La Niña winters are; 1950-1951, 1954-1955, 1955-1956, 1964-1965, 1967-1968, 1971-1972, 1974-1975, 1984-1985, 1995-1996, 2000-2001, 2011-2012, and 2016-2017
In general, temperatures have been colder than normal across the Northern Plains, and Upper Mississippi River Valley
There has been slightly wetter than normal conditions across far northeast Minnesota with near normal precipitation across the Northern Plains, and the majority of the Upper Mississippi River Valley

Observed Average Winter Temperature (°F)
Location	Year												Normal (1981-2010)
Location	1950-1951	1954-1955	1955-1956	1964-1965	1967-1968	1971-1972	1974-1975	1984-1985	1995-1996	2000-2001	2011-2012	2016-2017	Normal (1981-2010)
Duluth, MN	8.6	13.1	10.6	6.5	11.5	7.1	13.7	10.4	8.7	9.8	21.1	18.1	13.3
International Falls, MN	4.1	7.8	5.6	0.8	6.0	1.3	9.9	2.7	2.8	5.3	17.4	13.0	8.1
Brainerd, MN	M	M	7.0	4.3	12.8	4.2	12.0	8.4	7.2	8.4	22.3	17.2	14.4
Hibbing, MN	8.7	12.5	10.9	2.5	8.9	4.5	12.1	7.6	4.8	6.5	17.5	13.1	10.0
Ashland, MN	12.2	16.9	13.8	9.6	15.0	11.3	18.1	14.3	9.1	13.5	23.8	20.9	16.5

On the table above, values in red are observed temperatures above normal, while values in blue are observed temperatures below normal.

Observed Winter Precipitation (inches)
Location	Year												Normal (1981-2010)
Location	1950-1951	1954-1955	1955-1956	1964-1965	1967-1968	1971-1972	1974-1975	1984-1985	1995-1996	2000-2001	2011-2012	2016-2017	Normal (1981-2010)
Duluth, MN	5.97	2.85	3.28	4.41	1.90	4.97	5.60	2.96	3.99	3.94	2.33	5.03	2.98
International Falls, MN	2.88	2.93	2.69	1.49	2.34	1.95	4.33	2.35	2.35	0.93	2.03	4.94	2.00
Brainerd, MN	2.58	2.01	1.99	1.71	1.95	2.25	2.93	1.22	3.24	3.81	1.09	3.62	2.25

On the table above, values in brown are observed precipitation below normal, while values in green are observed precipitation above normal.

Observed Winter Snowfall (inches)
Location	Year												Normal (1981-2010)
Location	1950-1951	1954-1955	1955-1956	1964-1965	1967-1968	1971-1972	1974-1975	1984-1985	1995-1996	2000-2001	2011-2012	2016-2017	Normal (1981-2010)
Duluth, MN	68.0	52.1	45.4	54.2	17.8	69.1	64.1	35.5	81.2	66.2	32.9	50.9	49.5
International Falls, MN	29.1	43.6	35.5	23.2	26.0	35.2	65.4	37.5	69.5	33.5	37.2	54.9	40.8
Brainerd, MN	22.9	28.3	31.3	26.0	22.5	38.0	33.7	10.8	39.5	46.3	19.9	28.6	26.2

On the table above, values in brown are observed snowfall below normal, while values in green are observed snowfall above normal.

Highlights:

Duluth, International Falls, Brainerd, Hibbing, and Ashland have generally seen cooler than normal temperatures
Duluth, and International Falls have generally seen wetter than normal precipitation
Brainerd has seen 6 winters with drier than normal precipitation and 5 winters with wetter than normal precipitation
For Duluth and Brainerd, the majority of weak La Niña winters featured higher than normal snowfall
At International Falls, 8 out of the 12 weak La Niña winters saw below normal snowfall