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Lake Effect Snow

Page history last edited by Eric Modes 15 years, 3 months ago

 

Lake Effect Snow

 

 

 

 

 

Authors

 

Kyle Wanner     wanner1@illinois.edu

Eric Modes      emodes2@illinois.edu

Colby Suter        csuter2@illinois.edu

Scott Cohen      scohen3@illinois.edu

 

Table of Contents

 


Overview

 

    Lake Effect Snow is the result of arctic winds passing over a large body of warm water resulting in snow squalls that can produce several inches and even several feet of snow in a single event. Snowfall from such an event can last for days resulting in dangerous driving conditions and high costs for snow removal [1.1]. Lake Effect snowfall does not typically occur directly along the shoreline, but miles inland in places of higher elevation. Areas most severely affected lie on downwind shores of the Great Lakes in North America. For example, Toronto Ontario lies on the upwind shore of Lake Ontario and averages 54 inches of snowfall a year, while Syracuse New York lies on the downwind shore of Erie and averages 109 inches of snowfall annually [1.2].

 


  

Figure 1.1: MODIS image of the western Great lakes in North America.

The clouds that stream from the northwest to the southeast are produced by the lakes.


   

     

     Lake effect snow is occasionally produced on smaller lakes in numerous locations. However, the ideal conditions of very cold air passing over a large unfrozen body of water are best met over the expansive Great Lakes in the northern United States. These lakes remain unfrozen for much of the winter season and are subjected to frequent northwest winds from Canada. Throughout the world, there are virtually no other inland bodies of water that are as efficient and notorious for making lake effect snow. [1.3]

  

     One famous he 1946 Veteran's Day Snowstorm in Cleveland Ohio, which resulted in roughly 160,000 individuals without power, as nearly 70 inches (nearly 6 feet) of snow fell in some areas. In this particular instance, the heaviest snowfall was found 12 miles from the shoreline. More recently, February 3-11, 2008 saw 145 inches (over 12 feet) of snow on the Tug Hill Plateau on the eastern edges of Lake Ontario. 

 


  

Figure 1.2: Snow Plow clearing streets in Muskegon County, MI


  

     The impacts of lake effect snow are far reaching as nearly 40 million people live along these lakes in both Canada and the United States. Concern over how lake effect snow will change over the next century has been a hot topic in these regions. The notable increase in Lake Effect snowfall in the 20th century has been attributed to be an impact of global warming [1.4]. Warmer winters may keep more of the lake area unfrozen for longer during the winter season which could be responsible for this increase in Lake Effect Snow events. Other studies show that with warmer temperature, the passage of very cold polar air over the Great lakes will be less frequent thus reducing lake effect snow. Regardless of the outcome, residents in the Great Lakes Basin will be sure to monitor changes in climate as lake effect snow is a major part of their livelihood.

 

 

Description

 

     Lake-effect snow is a phenomenon that can produce intense, long-lasting snowstorms, which can cause millions of dollars worth of damage and lost productivity.  These storms form as a result of cold polar air masses moving over the warmer surface of a lake.  The temperature difference causes relatively shallow clouds to develop and ultimately dump large amounts of precipitation as they pass over land.


   

Figure 2.1: These graphics show lake-effect snow clouds forming over a lake. 


      These storms vary in size, strength, and duration based on many variables including the temperature of a lake, the temperature of the air mass, wind direction and speed, ice cover, and topography.  A single event can result in anywhere from a few inches to five feet of snow or more and can last up to several days.  The areas most affected by lake-effect snow are in areas referred to as snow belts.  These belts exist thirty to fifty miles inland on the downwind (southeast) shores of the Great Lakes in the United States and Canada. 


 

Figure 2.2: This graphic from the Weather Doctor gives a broader sense of lake-effect snowfall in the Great Lakes Region.  


     Lake-effect snow has wide-ranging impacts on the areas where it falls.  Strong lake-effect snowstorms can paralyze a city and cause widespread power outages for major cities like Cleveland, OH, Syracuse, NY and Buffalo, NY.  For example, Lake-Effect Snow Storm Aphid, which affected Buffalo in 2006, caused power outages for over a million people.  

     Lake-effect snow, like any other strong storm can also cause property damage.  The weight of the snow itself can cause roof and other structural damage.  Downed tree limbs are also very common results of lake-effect snowstorms.  In 2006, $571 million dollars worth of property damage was reported as a result of winter storms.


Figure 2.3: These two CNN clips illustrate how the residents deal with lake effect snow events.

 

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     These storms also broadly impact transportation making it nearly impossible to travel immediately following a large snow event.  Some people can remain snowbound for several days as crews are usually stuck at their homes for up to a few days until streets are sufficiently clear.  People are obviously unable to travel, go out to work, visit stores and shopping malls or go out to eat.  This greatly affects the productivity of the area as well as the area’s commerce.  People are forced to spend time and effort digging themselves out of the snow.  Injuries are also common due to the conditions and the labor involved in recovering from the storm.   At the heart of the problem is the shear volume of snow. Removing it is time consuming and costly.  However, most of the cities in the lake effect snow belts expect and are prepared for the snow.  


   

Figure 2.4: This graphic from the National Weather Service gives the average seasonal snowfall for the snow belts to the southeast of Lake Erie and Ontario.  The area between Watertown and Syracuse receives 200+ inches of snow annually and is referred to as the “Snow Capital of the East.” 


     Lake-effect snowstorms result in large amounts of lost time, money, and productivity for individuals as well as for their town.  However, not all aspects of the storms are negative.  For example, ski resorts in these areas depend on lake-effect snow to allow them to open earlier and to stay open longer during the season.  Without lake effect snow, they would lose large amounts of money!  


Formation

 

     Formation of Lake Effect Snow begins with cold air traveling over the warm water.  The air needs to be about -13°F (-25°C) to 23°F (-5°C) in order for lake effect snow process to begin and the lake must be unfrozen.  Additionally, the temperature difference between the air and water usually needs to be greater than 18°F (10°C).  Due to this fact, lake effect snow usually occurs when winds blow from the northwest to the southeast because these bring cold polar air from Canada.  Additionally, lake effect snow occurs mostly between the months of November and February because this is when the greatest temperature difference between air and lake water exists[3.1].  This difference can be seen Figure 3.1 which is a diagram how the temperature of the water in Lake Erie and the air temperature changes throughout the year[3.2].

 

 

 

Figure 3.1: Temperature difference between air and lake in Buffalo, New York is shown.

http://www.erh.noaa.gov/er/buf/lakeffect/lakeclimate.html


     When the cool air hits the upwind shoreline, it will begin to speed up due to less friction over water.  This creates divergence in the air at the surface, and to fill this void air descends from above at the front of the lake. This causes the air close to the upwind shoreline to be clear as seen in Figure 3.2 [3.3].

 

 

 

Figure 3.2: The air on the upwind shoreline is clear due to the divergence of air in that region. http://apollo.lsc.vsc.edu/classes/remote/graphics/satellite_images/lake_effect_snow.jpg


     As the cold air comes over the warm water, it begins to heat up just above the surface of the lake.  As this air becomes warmer, the saturation vapor pressure increases allowing for more moisture to be retained.  This causes the warm water to evaporate into the air just above the lake.  The air above the small layer of warm air is still cool, and this allows for destabilization of the air.  As the heating air by the surface of the lake gets warm enough, it will begin to rise in the cold atmosphere to form cumulus clouds.  The air above the lake can increase in temperature by as much as 36°F (20°C).  The clouds that form can grow in depth to about 2 km to 3 km (0.5 miles to 2 miles).  As these clouds grow, they begin to snow. Once the air hits the downwind shoreline, the air will slow down due to increased friction over land.  This causes convergence near the shoreline, driving more air upwards.  This increases the upward air movement within the cloud which enhances the formation of snow within the cloud and causes snow to fall within and downwind of the shoreline[3.4].  Thus lake effect snow is formed.  This entire process is illustrated in Figure 3.3 created by the NWS Buffalo’s lake effect snow webpage[3.5]. 

 

Figure 3.3: This illustrates the cool air coming over the warm lake, heating up the air, and destabilizing the air to begin to form clouds and eventually snow.

http://www.erh.noaa.gov/er/buf/lakeffect/form.html


     Wind speeds in order for lake effect snow to occur should be between 10 to 40 mph because this is slow enough to allow this process to occur[3.6].  Lake effect snow amounts can range from several inches to 5 feet of snow or more in one event.  The regions where this snow falls is very local to the shoreline and large amounts of snow typically fall within regions 30 to 50 miles inland of the great lakes.  Figure 3.4 illustrates how confined the lake effect snow process is to the shoreline[3.7].

 

 

Figure 3.4: Pockets of large amounts of snow can be seen next to different regions of the great lakes. 

http://www-das.uwyo.edu/~geerts/cwx/notes/chap10/lake_effect_snow.html


 

     Lake effect snow is forecasted by monitoring the air temperature above the lake, monitoring the water temperature of the lake, monitoring moisture of the air above the lake, monitoring direction and speed of wind.  These can be monitored through soundings, thermometers, Doppler radar, and surface dew point temperatures. Once lake effect snow conditions are present, meteorologists predict the type of lake effect snow to fall. There are 3 main types.  The first type is wind parallel rolls.  This forms because when the warm air begins to rise to form clouds, colder air is being replaced, and the cool air sinks.  This creates rolls parallel to the direction of the wind.  These rolls are usually 1 to 2 km wide and 4 to 6 km apart with the potential of being up to 10 km apart.  Wind parallel rolls tend to form with strong winds that blow across the short axis of a lake[3.8].  Figure 3.5 shows the rolls forming over Lake Michigan[3.9].

 

 

Figure 3.5: Wind parallel rolls form over Lake Michigan.

http://severewx.atmos.uiuc.edu/12/online.12.1.windparallel.html


 

     The second type of formation is shore parallel bands.  This forms when the warm air rising in the center of the lake causes air from both sides of the lake to rise towards the center of the lake.  This airflow causes a shore parallel band to form.  These typically form when winds are weak, but can form when winds are strong as well.  In this case the winds are parallel to the long axis of the lake[3.10].  This formation can be seen in Figure 3.6 below[3.11].

 

Figure 3.6 A shore parallel band forms over Lake Michigan.

http://severewx.atmos.uiuc.edu/12/online.12.1.shoreparallel.html


     The last lake effect snow formation is vortices.  The formation of this system is still not known in its entirety.  It is thought that horizontal wind shear, wind speed, topography, air stability, and temperature differences between the lake and air are components to the formation of vortices.  Vortices can be hurricane shaped, but vortices have winds around 5 to 15 knots and are 10 to 100 km in diameter[3.12].  A vortex is shown below in figure 3.7 [3.13]. 

 

Figure 3.7 A vortex forms over Lake Michigan.

http://severewx.atmos.uiuc.edu/12/online.12.1.vortex.html

 


 

 

Destruction

     The lasting, damaging impacts of lake effect snow are typically localized to within 50 miles of the shore of lake however, large-scale damage often results when these snow squalls hit the major metropolitan areas along the shores of the Great Lakes. Heavy accumulations of snow can cause extra weight on trees, causing them to fall over onto power lines and ultimately created widespread power outages.

 

Figure 4.1 Heavy, wet snow accumulates on trees.

http://www.magazine.noaa.gov/stories/mag222.htm

 

Also, heavy snowfall on roads and highways can affect traffic flow and can cause major damage. There are several recent instances of this kind of damage from lake effect snow. For example, on October 12-13 in 2006 Lake Aphid dropped 24” of snow on Buffalo, New York over a 16-hour period.

Figure 4.2. Lake Storm "Aphid"

http://vortex.accuweather.com/adc2004/pub/includes/columns/margusity/2006/aphid.gif

 

Buffalo, which sits east of Lake Erie, and its surrounding suburbs saw a total of $160 million in damage. The heaviest 2 to 3 inches of wet snow fell in the first few hours causing the most damage to “fully foliated” trees and, in effect, causing 400,000 households to lose power. In regards to traffic, a 105-mile stretch of the New York State Thruway was closed due to “clogged runways”.[4.1]

Figure 4.3 Heavy traffic accumulates in snowfall

http://blog.nj.com/ledgerupdates_impact/2007/11/large_A1SNOW20.jpg

 

     Another major storm to hit Buffalo was lake effect storm “Chestnut,” which occurred between November 20-23, 2000. Over this 60-hour period, the highest recorded snowfall was in the suburb of Stockton with a whopping 31”[4.2]. The timing of the immense snowfall caused traffic in Buffalo to become completely clogged until it came to a standstill, leaving thousands of people to spend the night in their automobiles[4.2]. The reason that Buffalo sees such damage is because the city is nestled in between both Lake Erie and Lake Ontario, leaving it to be a prime spot for the accumulation of lake effect snow.

 

Figure 4.4 Lake Storm "Chestnut"

http://www.erh.noaa.gov/er/buf/lakeffect/lake0001/c/stormc.html

 

Perhaps the most notable storm was “Locust,” which lasted for 10 days between February 3rd and the 12th in 2007[4.3]. While the Lake Erie region saw 42’’ of snow, the Tug Hill Plateau, located near the end of Lake Ontario, saw 141’’ of snowfall[4.3].

     Also is the 1996 Veterans Day storm in Cleveland, Ohio and the surrounding area. While certain areas saw up to 70” of snow, Lake and Cuyahoga counties had over 70,000 people lose power due to the accumulation of only 11-14” of heavy, wet snow[4.4]. These people lost power in the first 24 hours of the 6 day storm.

 


Case Study

 

Lake Storm Aphid

            This storm, known as Aphid, occurred in an area especially at risk for heavy lake-effect snow.  The storm affected Buffalo, New York.  Buffalo is in the middle of a lake-effect snow-belt, which can be seen in Figure 5.1, and commonly receives over 100 inches of snow each year[5.1].  The storm was uncommon only because of how early in the year it occurred, October 12-13, 2006.

 

Figure 5.1: This graphic highlights the snow-belt in which Buffalo, New York is located.  It lies to the southeast of Lake Erie and Lake Ontario.

http://content.answers.com/main/content/wp/en/thumb/0/06/350px-Snowbeltus.PNG


 

            The storm amassed 2 feet of snow in the most heavily hit areas, while the Buffalo region recorded anywhere from a foot to 2 feet of snow.  The storm broke the record for the snowiest day in Buffalo with 8.6 inches of snow falling on October 12.  However, this record was again broken the next day, October 13, when 10.9 inches of snowfall was recorded[5.2].  Aphid was also the earliest lake effect snow storm to ever hit Buffalo.  For occurring so early in the season, the snowstorm still recorded the 7th largest snowfall ever in Buffalo[5.3].  Figure 5.2 shows the amount of snow western New York received[5.4].

 

 

Figure 5.2: The amount of snow Aphid produced is shown in the Buffalo, New York region.

http://vortex.accuweather.com/adc2004/pub/includes/columns/margusity/2006/aphid.gif


            The storm devastated the Buffalo Region mainly due to enormous amount of tree damage.  It was estimated that 90% of the trees were damaged, and this was able to occur because most of the trees were still in full leaf causing the trees to accumulate more snow and weight.  Many of the trees that fell damaged power lines, cars, and houses.  This damage caused over 350,000 people to lose electricity, and more than 100,000 households were without electricity for over a week.  The cost of damage was estimated around 130 million dollars, mainly for the cleanup of debris from fallen trees.  3 people died from the storm itself.  2 died in car accidents during the storm, and the third died from being hit by a falling tree[5.5].  In the aftermath of the storm 10 more people died from pre existing conditions and carbon monoxide poisoning from the use of generators.  Additionally, it was estimated that several hundred people were injured from the storm and aftermath of the storm[5.6].  In Figures 5.3 and 5.4, the damage from Aphid can be seen.  Aphid also shut down transportation in western New York during the storm.  The Buffalo airport was shut down for the event, and a 105 mile stretch of the New York Thruway was closed due to the storm leaving many vehicles stranded[5.7].  Figures 5.5, 5.6, 5.7, an 5.8 portrays the conditions at the Buffalo airport and the conditions on the New York Thruway respectively[5.8][5.9].

 

 

 

Figures 5.3 and 5.4: Tree damage from the snowstorm.

http://upload.wikimedia.org/wikipedia/commons/0/05/Buffalo_snow_storm3.jpg

http://upload.wikimedia.org/wikipedia/commons/3/3c/Buffalo_snow_storm14.jpg

 

Figures 5.5 and 5.6: The airport in Buffalo closed down due the lake effect snowstorm.

http://upload.wikimedia.org/wikipedia/commons/9/9a/Officetower_kbuf_october13_06.jpg

http://www.usawx.com/thejourney248.htm

 

 

 

Figures 5.7 and 5.8: The New York Thruway is closed due to the snowstorm.

http://www.usawx.com/thejourney248.htm

http://www.usawx.com/thejourney248.htm


            The lake effect snowstorm was first predicted a week before the event on October 6, 2006.  However, most of the models were showing this storm would produce mainly rain.  A few days before the event the predictions were that lake effect rain would occur with a chance of some graupel or wet snow.  When October 12, 2006 arrived, the predictions had changed to 1 to 6 inches of wet snow would precipitate.  However, in the first phase of the storm from 3 P.M. to midnight 5 to 8 inches of heavy wet snow had fallen.  The second phase of the storm precipitated dryer snow after midnight, and in just 4 hours about another 12 inches of snow had fallen.  The storm was snowing 2 to 3 inches every hour.  Overall, 1 to 2 feet of snow fell in the Buffalo region, and all of this snow melted within the next 2 to 3 days[5.10].  Figure 5.9 shows a satellite image of Aphid, and Figure 5.10 shows the radar during Aphid[5.11][5.12].

 

 

 

 

 

Figure 5.9: This satellite image shows lake effect snowstorm Aphid

http://www.erh.noaa.gov/buf/storm101206.html

 

 

 

 

Figure 5.10: This radar image portrays lake effect snowstorm Aphid

http://upload.wikimedia.org/wikipedia/commons/9/98/October_12-13_radarloop_kbuf.gif


            A low pressure center passing over Lake Erie began the events.  Once the low pressure center passed over the Buffalo region a cold front followed.  This dropped temperatures over the lake and the Buffalo region.  The air temperature to lake temperature difference was incredible.  The lake was 62°F, while temperatures in Buffalo on October 12, 2006 were at 41°F and when snow started falling the temperature had dropped to 34°F [5.13].  Due to the large difference in air and lake temperatures cloud tops rose to 25,000 to 30,000 feet.  Additionally, CAPE values were very high for a lake effect snow event[5.14].

 

 


 

Vodcast

 

 

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Sources

 

Overview

1.1 Severe and Hazardous Weather, an introduction to high impact meteorology, second edition, Robert Rauber, John Walsh, Donna Charleviox

1.2 Lake-Effect Precipitation in Michigan. http://www.x98ruhf.net/lake_effect.htm , Robert J. Ruhf Retrieved on 11/01/2008

1.3 Severe and Hazardous Weather, an introduction to high impact meteorology, second edition, Robert Rauber, John Walsh, Donna Charleviox

1.4 Lake-Effect Precipitation in Michigan. http://www.x98ruhf.net/lake_effect.htm , Robert J. Ruhf Retrieved on 11/01/2008

 

Description 

2.1. Glendale Community College Earth Science Image Archive. http://www.gc.maricopa.edu/earthsci/imagearchive/lake_effect_snows.htm 

2.2.  Heidorn, Keith C.  "Lake-Effect Snow Climatology In The Great Lakes Region." The Weather Doctor.  http://www.islandnet.com/~see/weather/elements/lkefsnw3.htm

2.3. CNN Video. http://www.cnn.com/video/

2.4 The National Weather Service. http://www.erh.noaa.gov/buf/hydro_maps/snowseas.gif

 

Formation

3.1. Charlevoix, Donna J., Robert M. Rauber and John E. Walsh., "Severe and Hazardous Weather: An Introduction to High Impact Meteorology. Second Edition" Kendall Hunt (2005), 208-210.

3.2. http://www.erh.noaa.gov/er/buf/lakeffect/lakeclimate.html

3.3. http://apollo.lsc.vsc.edu/classes/remote/graphics/satellite_images/lake_effect_snow.jpg

3.4. Charlevoix, Donna J., Robert M. Rauber and John E. Walsh., "Severe and Hazardous Weather: An Introduction to High Impact Meteorology. Second Edition" Kendall Hunt (2005), 208-210.

3.5. http://www.erh.noaa.gov/er/buf/lakeffect/form.html

3.6. Haby, http://www.theweatherprediction.com/winterwx/lesnow/

3.7. http://www-das.uwyo.edu/~geerts/cwx/notes/chap10/lake_effect_snow.html

3.8. Charlevoix, Donna J., Robert M. Rauber and John E. Walsh., "Severe and Hazardous Weather: An Introduction to High Impact Meteorology. Second Edition" Kendall Hunt (2005), 214-215.

3.9. http://severewx.atmos.uiuc.edu/12/online.12.1.windparallel.html

3.10. Charlevoix, Donna J., Robert M. Rauber and John E. Walsh., "Severe and Hazardous Weather: An Introduction to High Impact Meteorology. Second Edition" Kendall Hunt (2005), 215-218.

3.11. http://severewx.atmos.uiuc.edu/12/online.12.1.shoreparallel.html

3.12. Charlevoix, Donna J., Robert M. Rauber and John E. Walsh., "Severe and Hazardous Weather: An Introduction to High Impact Meteorology. Second Edition" Kendall Hunt (2005), 218.

3.13. http://severewx.atmos.uiuc.edu/12/online.12.1.vortex.html

 

Destruction

4.1. Hamilton, Robert S.; Niziol, Thomas; Zaff, David. “A Catastrophic Lake Effect Snow Storm Over Buffalo, NY October 12-14, 2006.” NOAA National Weather Service: Buffalo, NY. < ams.confex.com/ams/pdfpapers/124750.pdf>

 

4.2. “Lake Effect Storm ‘Chestnut’: November 20-23, 2000.” NOAA National Weather Service: Buffalo, NY. <http://www.erh.noaa.gov/er/buf/lakeffect/lake0001/c/stormcsum.html>

 

4.3. “Lake Effect Storm Season 2006-2007.” NOAA National Weather Service: Buffalo, NY. http://www.erh.noaa.gov/buf/lakeffect/06-07.html 

 

4.4. “Veteran’s Day Lake Effect Snow Storm: a case study.” The Weather World 2010 Project. Department of Atmospheric sciences at the University of Illinois at Urbana-Champaign. <http://ww2010.atmos.uiuc.edu/(Gh)/arch/cases/961109/home.rxml>

 

Case Study

5.1. http://content.answers.com/main/content/wp/en/thumb/0/06/350px-Snowbeltus.PNG

5.2. http://www.usawx.com/thejourney248.htm

5.3. http://www.erh.noaa.gov/buf/storm101206.html

5.4. http://vortex.accuweather.com/adc2004/pub/includes/columns/margusity/2006/aphid.gif

5.5. http://www.aparchive.com/OneUp.aspx?xslt=1p&st=k&kw=buffalo%20snow%20october&showact=results&sort=relevance&page=1&sh=1180&kwstyle=and&dbm=VArchive&adte=1229022827&rids=48929e263917253733a103733951afc9&dah=-1&pagez=20&

5.6. http://www.nationmaster.com/encyclopedia/Lake-Storm-%22Aphid%22

5.7. http://www.aparchive.com/OneUp.aspx?xslt=1p&st=k&kw=buffalo%20snow%20october&showact=results&sort=relevance&page=1&sh=1180&kwstyle=and&dbm=VArchive&adte=1229022827&rids=2b9df7fc5f2adcabca3d4b60851be498&dah=-1&pagez=20&

5.8. http://commons.wikimedia.org/wiki/Category:October_13,_2006_snow_storm_in_Buffalo,_New_York

5.9. http://www.usawx.com/thejourney248.htm

5.10. http://www.erh.noaa.gov/buf/storm101206.html

5.11. http://www.erh.noaa.gov/buf/storm101206.html

5.12. http://upload.wikimedia.org/wikipedia/commons/9/98/October_12-13_radarloop_kbuf.gif

5.13. http://www.nationmaster.com/encyclopedia/Lake-Storm-%22Aphid%22

5.14. http://www.erh.noaa.gov/buf/storm101206.html

 

 

 

 

 

 

 

 

 

 

 

 

 


 

 

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