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Landscape Ontario Snow and Ice Symposium

Join Rob Kuhn, Severe Weather Meteorologist at the Ontario Storm Prediction Centre, for a discussion on Southern Ontario's unpredictable winter weather. Learn about winter storm tracks, major snowstorms, ice storms, lake effect snow, and more. Don't miss this opportunity to ask questions and gain insights into Ontario's unique winter climate.

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Landscape Ontario Snow and Ice Symposium

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  1. Landscape Ontario Snow and Ice Symposium Southern Ontario’s Wacky Winter Weather 02-September-2010 Rob Kuhn Severe Weather Meteorologist, Ontario Storm Prediction Centre Toronto, Ontario

  2. Outline Winter weather stuff Watch, warning and weather statements Weather radar Winter Storm Tracks Major Winter Snowstorms Major Winter Ice Storms Lake Effect Snow Questions?

  3. Job Profile and EducationEnvironment Canada-Ontario Storm Prediction Centre- Honours BSc (UWO)1984 MSc Meteorology (U of T) 1987 Government Operational Meteorology Course 1987-88 Internship Winnipeg 1988-1989 Internship Toronto 1989-1990 Lead/Severe Weather Meteorologist 1995-present Continuous learning (courses, teaching, R&D) Outreach Shift work 24/7 Your income taxes help pay my salary!

  4. Some Winter Weather Stuff http://www.islandnet.com/~see/weather/graphics/photos/glsnow.gif Lake effect snow a major contributer!

  5. Some Winter Weather Stuff Snowfall amounts Southern Ontario(not snowbelts) Average total winter snow … about 100-150 cmAverage number of days with snow .. About 65Snow Season .. Nov 15 to April 15 Tr-2 cm - 1-3 times a week 2-10 cm – 2-5 times a month 10-20 cm – 2-4 times per winter 20-30 cm – once every 2-3 years Close to 30 cm – January 199940 cm or over – March 07-08, 2008 Biggest Ever – 76 cm Nov 24-25, 1950 Many small snowfalls with drifting snow from lake effect flurries

  6. Some Winter Weather Stuff Snowfall amounts Southern Ontario Snowbelts Average total winter snow … about 200-300 cmAverage number of days with snow .. About 90Snow Season .. Nov 01 to April 15 Tr-2 cm - 3-5 times a week 2-10 cm – 2-5 times a month 10-30 cm – 5-10 times per winter 30-50 cm – 1 event annually50 cm or over – probably 1-2 times each two years Biggest snows - 200 cm over 2-3 days Many snowfalls with drifting snow from lake effect flurries and snowsqualls

  7. Some Winter Weather Stuff Blowing And Drifting Snow Average winter wind speed = 15 km/hStrongest winds from SW-NW = 50 km/h gusts common Max winter wind speed = 60-70 km/h Max winter wind gusts = 80-90 km/h Highest gust on record = 119 km/h March 30, 1981 Fresh snow drifts with 15-20 km/h winds Fresh snow blows around starting with 30-40 km/h winds Whiteouts can be an issue with 40 km/h or more winds

  8. Some Winter Weather Stuff Freezing Rain In Southern Ontario Average number of freezing rain events … 5Usual amount of freezing rain .. 1-5 mm Large ice storms (5-10 mm) - once every couple of years Major Ice Storm (>10 mm) – once every 5 years(ice pellet concrete event April 2003)

  9. Winter Severe Weather(and types of warnings) • Blizzards – heavy and blowing snow, high wind chills • Snowfall – 15 cm or more in 12 hrs • Snowsqualls – lake effect snowstorms • Freezing Rain – 2 or more hours - icing • Strong Winds – 60 Gusting to 90 km/h or more • Heavy Rain – 50 mm/24 hrs

  10. Weather Watch and Weather Warning • Severe Weather Watch-the potential for severe weather* Be Alert * • Severe Weather Warning- severe weather will soon occur or is occurring *** Take Action ***

  11. Winter Storm Watch Potential of Winter Storm Within 1-3 Days Winter Storm Watch for: Kitchener – Cambridge – Region of Waterloo. A low pressure area from Texas is moving northeast towards Southern Ontario and is expected to intensify into a winter storm as is moves in Thursday. Current indications show that snow from this developing winter storm will move into the region beginning tomorrow afternoon. The snow may change over to freezing rain by Friday morning as the storm centre passes by just to the south of the district. Significant amounts of snow and freezing rain are possible from this developing storm. There is still some uncertainty as to the exact track of this storm so actual snow and freezing rain amounts may change accordingly. Travelling conditions are expected to deteriorate by tomorrow evening with hazardous driving conditions quite possible. Motorists should alter travel plans accordingly. Environment Canada is closely monitoring this situation and warnings may be issued as required. End/Kuhny

  12. Snow Squall Watch**New 2009-2010** Potential of Snow Squalls Within 18 hrs-2 Days • Localized Lake Effect Snow Storms • 15 cm or more snowfall in 12 hours • visibility in snow squall < ½ km for 3 or more hours = from wind and/or heavy snow • Waterloo Region usually gets ~ 5 of these per winter= 20-30 events/winter in snowbelts

  13. Snow Squall Watch Potential of Snow Squalls Within 1-2 Days Snow Squall Watch for: Kitchener – Cambridge – Region of Waterloo. Snow squalls are expected to develop after midnight tonight as a strong cold northwesterly flow of fresh arctic air picks up moisture from the relatively mild waters of Lake Huron. Local snowfall amounts of 15 cm are quite possible overnight into Thursday morning in the strongest snow squalls. In addition strong northwest winds gusting to 70 km/h will cause frequent near zero visibility in blowing snow. Dangerous winter travelling conditions from whiteouts in bursts of heavy snow and blowing snow are anticipated. Motorists should alter travelling plans accordingly. The threat of snow squalls will end Thursday afternoon as winds diminish. Environment Canada is closely monitoring this situation and warnings may be issued as required as the event draws closer. End/Kuhny

  14. Winter Weather Warning Severe winter weather imminent or occurring 14-Jan-2007 Snowfall warning for: Kitchener – Cambridge – Region of Waterloo. A strong low pressure system moving from Texas through Ohio to New England will bring 15 cm of snow and ice pellets overnight and Monday. There is also a chance of some freezing rain. This may be quite a high impact storm as most areas have had little or no snow or freezing rain until now. Motorists should exercise extreme caution and be prepared to allow much extra time to reach their destination if travel is absolutely necessary. Dangerous winter driving conditions are likely..especially during the Monday morning hours when the snow and freezing rain may be heaviest. End/Lee/Kuhn/OSPC

  15. Special Weather Statement Hazardous winter weather imminent or occurring Warning Criteria not quite met WOCN11 CWTO 070939 Special weather statement Issued by Environment Canada Ontario region. 4:39 AM EST Wednesday 7 November 2007. Special weather statement issued for.. London - Middlesex Oxford - Brant York - Durham Huron - Perth Waterloo - Wellington Dufferin - Innisfil Grey - Bruce Barrie - Orillia - Midland. ..The first widespread lake effect snow event of the season.. Lake effect snow and rain showers which developed to the Lee of Lake Huron and Georgian Bay in a wake of a departing fall storm will continue today. At 4:30 AM radar indicates the heaviest activity between Collingwood and Innisfil and then down to Markham. Some communities inland from the southeast shores of Georgian Bay and Lake Huron may have received accumulation of 5 or so centimetres of wet snow. Another 5 centimetres are expected today. It should be emphasized that these amounts will be very localized and any snow which falls will be moisture-laden and may melt and quickly compact As it contacts the warm ground. Nevertheless.. This could make for some slippery driving conditions in time for the morning commute today especially on highway 400. Listen for further statements. Additional information may also be found by consulting the latest public forecast. END/TUGWOOD/ROS

  16. Winter Weather Effects • Often high impact • Poor road conditions from heavy and blowing snow • Numerous accidents (also from poor driving habits) • Ice accretion from freezing rain • Flooding during sudden thaws with rain • Snow days (work and school) • Have an Emergency Kit in the car and dress appropriately • flares • shovel • flashlight/candles/matches • blanket/warm clothes/boots • bottled water/granola bars • Cell phone/BlackBerry

  17. Weather Radar • Radar transmits beam out horizontally • Receiver at radar station picks up some return signal reflected off of rain, snow, hail

  18. Weather Radar • Main Problem: -Earth surface is curved -Radar beam goes out fairly straight -Hence looks at precipitation aloft in areas away from the radar †

  19. Weather Radar Another problem: Snow, rain and wet snow reflect differently = have to adjust for this all the time = snow rate makes rain echoes look much heavier

  20. Weather Radar More problems = heavy rain/snow near the radar can block the radar beam from detecting more distant precipitation = radar will show precipitation aloft even if it dries before reaching the ground

  21. Weather Radar Radar beam too high = beam can go above the clouds and miss the precipitation = can be an issue with snowsqualls

  22. Weather Radar More information found at http://www.msc-smc.ec.gc.ca/cd/factsheets/weather_radar/index_e.cfm

  23. Weather Radar Anomalous propagation = beam forced down to the ground on clear calm nights = radar “sees” the ground It was a clear night!!

  24. Phil’s Arctic Iceboat MAIN WINTER STORM TRACKS Alberta Clipper Colorado Low East Coast Low Texas/Louisiana Low

  25. Winter Storms -10°C Anatomy of a Winter Storm Flurries 10°C

  26.    10-20 cm snow Winter Storm Tracks L   Alberta Clipper 2-5 cm snowShowersFlurries (Trace - 2 cm)Often windy

  27.      15-30 cm snow Winter Storm Tracks 2-5 cm snow/Ice pelletsTr-5 mm freezing rain L     Flurries (Trace - 2 cm)Usually windy Colorado Low Rain/showers

  28. Another Major Winter Storm – Sunk the Edmund Fitzgerald in 1975

  29.            20-40 cm snow  Winter Storm Tracks 2-10 cm snow/Ice pelletsTr-5 mm freezing rain L  Flurries (Trace - 2 cm)Usually windy Texas/Louisiana Low Heavy Rain/showersThunderstorms possible

  30.            20-60 cm snow Winter Storm Tracks Light snow for KW (2-5 cm)Usually windy  L East Coast Low  Isolated flurries (Trace)Usually windy Waterloo Region brushed by these storms

  31. Winter Storm Tracks How can we get a big dump in Southern Ontario???

  32.            15-30 cm snow  Winter Storm Tracks L 2-10 cm snow/Ice pelletsTr-5 mm freezing rain  Texas Low passes south of us Snow – freezing rain - snow Usually 1 of these each winter This track more rare than before 1980 Big Snowstorms For Southern Ontario Heavy Rain/showersThunderstorms possible

  33. Very Heavy Snow

  34. Very Heavy Snow

  35. Very Heavy SnowBracebridge Dec 2009 100-200 cm snow in 2 days Photo courtesy George Kourounis

  36. Winter Storms How Can We Get An Ice Storm In the Tri-Cities?

  37. Freezing Rain Formation Snow Warm above freezing air layer above cold air near the ground. Rain Freezing Rain

  38.          Winter Ice Storm Tracks  2-5 cm snow/Ice pellets5-25 mm freezing rain L   A tale of two or three Texas Lows - Passing just south of us - 2-3 periods of freezing rain - one of these types every 2-3 years - no change over to rain Major Ice Storms For Waterloo Region L 

  39. Major Ice Storm This one caused major damage in Eastern Ontario and Quebec

  40. A Major Ice Storm Jan 1998 Ice Storm – 10 cm Ice Accretion

  41. Freezing Rain

  42. Freezing Rain

  43. Freezing Rain Ice accumulation heavy enough to bend entire trees!

  44. Snowsqualls Lake Effect Snow Waterloo Region

  45. Lake Effect Snow Waterloo region is on the edge of the Lake Huron snowbelt Cold arctic air picks up moisture from Great Lakes Winds blow in moisture and flurries to our area Heaviest lake effect snow usually just to our West and North Most common snow amounts for us .. Trace to 2 cm Snowsqualls – local lake effect snowstorms with heavy snow and/or strong winds There are exceptions though!!!!

  46. Snowsqualls Lake effect snow in one area depends on the wind direction and speed! Remember – very local snowstorms Waterloo Region gets several snowsquall events each year!

  47. Lake Effect Snow Southwest winds Usually trace or nothing Different story Niagara/Ern Ont/Bruce/Parry Sound

  48. Lake Effect Snow West winds – usually tr-2 cm Local 30 cm near lakes

  49. Lake Effect Snow Northwest winds – best direction - 5-10 cm often occurs

  50. Lake Effect Snow Northerly winds“Traditional case”

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