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Above animation available at the ARG! Cartoon Animation Studio.

Duluth (Orographic City) Local Influences

Lake Superior and the surrounding higher terrain greatly influence snowfall and other weather in Duluth, MN and the rest of the north shore of the lake. People unfamiliar with Duluth may be surprised at how much the rise in elevation within the city acts like a mountain range. Forecasters in the area however know the effects only too well. Duluth is an excellent example of a microclimate or mesoclimate.

Please note that a few of the weather processes are debatable as to the extent of their application or significance. They are included for consideration.

Brief Description of Duluth, MN

Duluth is located at the narrow western tip of Lake Superior along a ridge that runs along the north shore of the lake. Lake Superior’s North Shore is oriented from east-northeast to west-southwest. Elevation increases abruptly near the lake shore on both sides of the lake. The city of Superior, WI, across the harbor from Duluth, is generally flat but with the hills a little farther from the lake. Duluth itself is built partially on the side of the hill. Some of the city sits on a narrow strip of flat land at the bottom of the hill while the rest is built inland beyond the ridge crest. Elevation within the city rises up to around 800 feet from the lake shore to beyond the ridge crest. More specifically, the elevation at Duluth International Airport is 817 feet higher than at Sky Harbor Airport.

Duluth's diverse terrain and proximity to Lake Superior contribute to large differences in snowfall within the city both seasonally and during many individual storms. Seasonal snowfall on top of the hill averages between 80 and 85 inches, roughly 20 inches more than at the bottom. Many of the processes affecting Duluth’s snowfall are similar to those induced by mountain ranges and that occur in other areas of the Great Lakes.

Increasing Duluth's Snowfall

Decreasing Duluth's Snowfall...Yuck!

Other Local Effects

General References

Employees of the National Weather Service in Duluth, MN

Meteorological Education and Training (MetEd) website operated by the Cooperative Program for Operational Meteorology, Education, and Training (COMET®) at of the University Corporation for Atmospheric Research (UCAR).

American Meteorology Society’s “Glossary of Meteorology”

Additional references are included with many of the separate entries.