Isle Royale Localization

Surface Air Temperatures

Winter temperatures are less severe when waters are open due to relatively warm surface waters

Island temperatures are generally cooler (warmer) than the mainland in summer (winter)

Comparison of average highs for Isle Royale (red) and Kelliher, MN (blue)Source: http://www.weather.com/weather/wxclimatology/monthly/graph/USMI0431

Source: http://www.epa.gov/greatlakes/atlas/images/big03.gif

Comparison of average lows for Isle Royale (red) Kelliher, MN (blue)Source: http://www.weather.com/weather/wxclimatology/monthly/graph/USMI0431

Isle Royale

Kelliher, MN

PrecipitationComparison of average precipitation for Isle Royale (red) and Kelliher, MN (blue)Source: http://www.weather.com/weather/wxclimatology/monthly/graph/USMI0431

The island generally receives less (more) precipitation during summer (winter) than the mainland

Source:http://www.wunderground.com/blog/weatherhistorian/article.html?entrynum=8

Isle Royale

Kelliher, MN

Lake Ice Formation

Warming surface water temperatures

Surface winds modify ice location, form, and distribution

Warming surface air temperatures (winter and/or summer)

Increased mixing of water layers brings relatively warm deep waters (during winter) to the surface

Increased wind and wave action

Amount of ice cover from previous season - less (more) allows longer (shorter) period of absorbing solar radiation

Source: http://www.epa.gov/greatlakes/atlas/images/big03.gif

Extreme Events

The most extreme events have occurred in November when the weather transitions from fall to winter Source: http://www.wunderground.com/blog/weatherhistorian/comment.html?entrynum=5

November 9-12 has had:1) the deadliest late-season tornado outbreak in the north-central United States, 2) deadliest Great Lakes storm, 3) most intense frontal passage in United States history, 4) deadliest blizzard in Minnesota history, and 5) the 2nd most intense low pressure system on record for the Midwest (only surpassed by the event of October 2010). Source: http://www.wunderground.com/blog/weatherhistorian/comment.html?entrynum=5

Events are accompanied by drastic changes in air temperatures and/or intense amounts of precipitation falling