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Michigan's Lake Breeze Zone

Some questions about the Michigan's "Lake Breeze Zone":

* What exactly is it? Does it have to do with an onshore breeze from Lake Michigan?
* How does it work as a boundary?
* How far inland does it extend?
* Does it oscillate back and forth like a dryline?
* Does the east side of Michigan also experience it?
* Is it always a consideration, or is it sometimes stronger, sometimes weaker, and sometimes non-existent?
* Is it seasonal--i.e. nonexistent in winter?
* I've never heard of the Lake Breeze Zone mentioned except in Michigan forecasts. Seems like other Great Lakes states would experience such a phenomenon. Do they?
 
Source: AMS Glossary
lake breeze—A wind, similar in origin to the sea breeze but generally weaker, blowing from the surface of a large lake onto the shores during the afternoon; it is caused by the difference in surface temperature of land and water as in the land and sea breeze system.
In addition to area, the depth of the lake is an important factor; a shallow lake warms up rapidly and is less effective as the source of a lake breeze in summer than is a deep lake. Lake breezes are well developed around the Great Lakes of North America, where they temper the summer heat.

Source: NWS Detroit Glossary
Lake/Land Breeze: A lake breeze occurs when prevailing winds blow off the water, while a land breeze indicates winds blowing from land to sea. Both are caused by the difference in surface temperature (heating) of the land and water. As a result, a lake breeze occurs during the day while a land breeze happens at night.

A few links, about Lake Breezes

A Lake and Land Breeze Primer
http://www.yorku.ca/pat/research/dsills/primer.html

Lake Breeze
http://www.suite101.com/article.cfm/13646/93996

Lake Breezes
http://www.crh.noaa.gov/apx/lakebreeze.shtml

Lake Breezes Linked to Severe Weather
http://www.ec.gc.ca/science/sandesept01/ar...article5_e.html

I will add more on the subject later.

Mike
 
Chicago gets lake breezes many times durning the year, many think its seasonal but in winter the lake keeps downtown Chicago a lot warmer than the burbs.

In NE illinois lake breezes sometimes goes many miles inland, ive seen them move into the far western and southern burbs of the area (40+ miles) obviously the change is much more signifigant the closer to the lake

you can almost always pick up lake breezes on the LOT radar
 
Some questions about the Michigan's "Lake Breeze Zone":

* What exactly is it? Does it have to do with an onshore breeze from Lake Michigan?
* How does it work as a boundary?
* How far inland does it extend?
* Does it oscillate back and forth like a dryline?
* Does the east side of Michigan also experience it?
* Is it always a consideration, or is it sometimes stronger, sometimes weaker, and sometimes non-existent?
* Is it seasonal--i.e. nonexistent in winter?
* I've never heard of the Lake Breeze Zone mentioned except in Michigan forecasts. Seems like other Great Lakes states would experience such a phenomenon. Do they?

The Chicago area experiences lake cooling rather frequently in the spring and summer, and maybe our climate can help answer your question.

Note: the lake breeze I'm talking is that generated by the lake itself, not necessarily the effect of synoptic-scale wind patterns blowing lake air around. It generally comes about when surface temperatures over land exceed the lake temperature by about 10 F and surface winds are under about 10 mph. (A converse effect on calm winter days is certainly possible, but I know little about offshore weather during the winter. It may give an extra kick to lake storms along the southern shore of the lake...)

In early spring, the lake breeze is often attended by haze or fog. I've seen clouds of fog blow in off the lake in Chicago and climb over steel facilities in Gary. It's actually quite impressive to watch.

Later in the spring, the lake temperature is rising through the 40s and 50s. In regimes of warm air and light winds, the lake breeze forms in the early afternoon (usually) and can proceed 20-40 miles inland without synoptic support.

Under the lake airmass, I think convection is repressed by two mechanisms. A shallow pool of cool, relatively dry air cuts it off at low levels while, in areas where the lake breeze is divergent like NW Indiana and the south suburbs of Chicago, air sinks and clobbers the convection from above.

At the boundary between lake and Gulf air in Indiana and Illinois, typically winds off the lake run into light yet prevailing west or southwest winds. The air has nowhere to go but up, so convection is favored (but not certain!). Of course, if the lake airmass is marching inland, any convection its inland boundary triggers gets cut off. My guess would be that the boundary between lake and Gulf air in Michigan would not be so sharply drawn on many days as it is on the western shore, if only because winds tend to flow from a westerly direction anyway.

The parts of IL and IN affected by lake breezes vary with the temperature of the lake, the temperature of the surrounding air and near-surface winds generated by synoptic (large scale) systems. That is, the lake breeze travels inland different distances on those days it does develop. And instead of oscillating back and forth, I get the impression that the boundary collapses when temperatures fall at night -- usually inland temperatures fall below the lake temperature every calm night.

Lake Michigan does mess with the weather in fall and winter as well, but usually as part of a larger synoptic situation. Lake effect snows in winter and lake-effect showers in September are the most prominent of such effects, though others have been observed. Occasionally though, mesoscale systems that look like toy hurricanes develop over the lake; they are far weaker than any tropical system.
 
Southern Ontario gets lake breezes all the time. Sometimes on a hot humid summer day, they can appear as almost solid white lines moving inland from the lakes on satellite. In southern Ontario, lake breezes coming from lakes Ontario, Erie and Huron, usually converge. A line from Windsor to Barrie is a convergence zone, and as a result the area is known as Ontario's tornado alley. When lake breezes converge, interesting things can happen. Sometimes lake breezes can help add rotation to existing storms.

Many times, areas right along the lakes will not receive any of the storms because they are in a lake breeze shadow.

Lake breezes mostly occur during the spring and summer. They only go through the area once. The stronger the lake breeze, the faster it travels inland.

Forecasting thunderstorm initiation associated with lake breezes is very tricky because you do not know where and when a storm will fire up along the line. The air needs to be fairly humid and unstable so that the lake breeze can have something to push up as it plows inland. Once a lake breeze goes through, you may experience cooler drier and fresher air, sometimes smelling like lake air. It's a nice relief on a hot day.

Here is a good report on Ontario lake breezes done by Dave Sills of EC and York University:
http://www.yorku.ca/pat/research/dsills/primer.html

and some info on rare late season events
http://www.yorku.ca/pat/research/dsills/rare.html

and an essay called ELBOW: An Experiment to Study the Effects of Lake Breezes On Weather in Southern Ontario
http://www.yorku.ca/pat/research/ELBOW/cmosbull.htm

as well as ELBOW 2001
http://www.yorku.ca/pat/elbow2001/

For other articles and photos of southern Ontario weather, check out
http://www.yorku.ca/pat/research/dsills.html
 
Thanks to you all for the information and the links! I'm particularly interested in this since I've noticed how storms often seem to fire or intensify to my east in Ionia County and to my south in Barry and Kalamazoo Counties. I've thought that this must have something to do with Kent County's position relative to Lake Michigan.
 
Here is the lake breeze moving off lake michigan into Chicago metro
1309016c.jpg

1309016d.jpg
 
Chicago gets lake breezes many times durning the year, many think its seasonal but in winter the lake keeps downtown Chicago a lot warmer than the burbs.

In NE illinois lake breezes sometimes goes many miles inland, ive seen them move into the far western and southern burbs of the area (40+ miles) obviously the change is much more signifigant the closer to the lake

you can almost always pick up lake breezes on the LOT radar

I've felt the damn thing in Dekalb and Rockford when it's really strong. It was 82 degrees, then it fell to 58! :lol: I remember that happening for several days during Spring 2003
 
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