Moving to Duluth, curious about the lake effect - is there a 'boundary' where it diminishes?

[ocsid]

If you're talking about snow, Duluth generally does not get what is commonly known as lake effect snow.
Lake effect snow occurs when the great lakes are open, but the atmosphere is cold and sucks up moisture from the lake. Because weather generally moves from west to east in that area, Duluth being at the westernmost point of the lake, there's no moisture to the west to cause lake effect snow to drop on Duluth.

Lake effect snow tends to start occurring somewhat in areas about 20 miles to the east. The Bayfield peninsula gets hit at times, but the heaviest lake effect in the region takes place in the UP, where they get 250 inches of snow a year. Duluth isn't even close to that.

If you're just talking about temperature, it's really weird in the summer. I've been in Duluth when it's been 40 degrees, and just 20 miles east, it's 70 degrees. The most drastic was 90 degree weather in Iron River and Brule, and 50 degrees on the lake shore near Port Wing.

[tvdxer]

I can't believe I didn't see this thread.

As far as temperature, it is generally warmer in the winter and colder in the summer by the lake. Often, the differences are subtle but they can be extreme, especially during spring and early summer. The boundary for the "lake effect" varies in location, but rarely goes past the border of Aitkin and Carlton Counties to the west and Pine and Carlton counties to the south, and is often limited to topographically to the areas of lower elevation within the city itself and Superior, Wisconsin. That means you can be sweating at 80F without air conditioning in Hermantown or Woodland or by the mall and thinking it would be a good day to go to the beach, only to find that it is 50F at Park Point weather station (KDYT)!

Rarely but surely, I've noticed a strange effect in the summer, perhaps due to adiabatic heating, where the temperatures by the lake become warmer than those at the Airport or farther inland, such as in the July 2006 heat wave. I believe a temperature of 108F/42C was recorded at the Duluth Harbor Station, although the official record stands at 106F, recorded a little ways' up the hill in 1936.

[Beenaroundabit]

I live on the North Shore. Many times it will be raining at my house, but snowing up on top of the hill, near the mall.

Oddly enough, the most noticeable temperature differences seem to be the opposite: warmer on the hill, but colder by the lake. This is more evident in the fall and spring.

[joe_obody999]

I often experience 20 or even 30 degree drops in temperature driving from the Mall (on top of the hill, the plateau of the city, as you go north) towards downtown, in summer. An air conditioning effect. Within a quarter of a mile! So in summer you can have clammy almost cold fogged in weather sometimes nearer the lake, on the hillside, but drive up to the shopping mall / Target Store area and drive out of it into hot sunny weather-- so if you want more sun then rent/buy a home up on the plateau.

Also as you go east and north to the north shore, to the east end of town, e.g. 60th ave east, etc, it can get cold in summer, i have seen 20 degree drops in temp there compared to downtown. Has a lot to do with the wind off the lake, because Lake Superior is always ice water or frozen over, so a wind from the east or south can blow that cold air off the lake and into parts of duluth and really chill things up, which can be nice on hot days of summer. But also can cause lots of fog and despair (but as i said, you can drive 5 minutes up to the mall and into sunshine and warmth!). If I were to buy again, I would have bought up by the Mall, Hermantown area, to have sun and warmth; then choose to drive to the lake for relief from the heat in summer.