Term
| Why is Montreal so vulnerable to ice storms? |
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Definition
- cold air gets trapped in the St. Lawrence river valley, causing freezing rain
- bimodal wind direction |
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Term
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Definition
- water below 0 degrees but not solid, freezes to the first object it comes into contact with
- freezing rain storm droplets freeze on impact |
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Term
| What are synoptic ice storm conditions? |
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Definition
1. when the north of a warm front and the west of a surface cyclone coolide (72% of events)
2. when the north of a cold front is in a cold- air dome with a high pressure system (52% of events) |
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Term
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Definition
- when warm moist air (from the gulf of mexico ) meets cold dense air from north
- warm air will flow over the cold dense air |
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Term
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Definition
-layer in which the temperature increases with height
- forms when warm moist area from south flows above dome of cold air
- the precipitation falls as snow, then melts, and then is cooled again to supercooled water freezes on ice nuceli to make ice pellets |
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Term
| What are factors affect the severity of an ice storm? |
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Definition
Persistence- duration (ex. Mtl ice storm so long)
Intensity- how fast is the precipitation
Phase- is the liquid supercooled?
Location- is the area particularly vulnerable? |
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Term
| What made the 1998 Montreal ice storm such an anomaly? |
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Definition
- most ice storms last less than 5 hours but this one lasted over 5 days
- more than 80 hrs of freezing frain in Ottawa and MTL
- nearly stationary frontal system
- more than one billion dollars in damages
- power outages = hypothermia |
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Term
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Definition
- listen to the radio for freezing rain warnings
- try to stay warm! |
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