Winter Weather Awareness Week 2019

Monday

Preparedness

We will explore what precautions you can take to mitigate against New York's harsh winters and how you can become ready and more resilient.

It has been proven that the best way to prepare for extreme weather is to have a plan.  Never let a winter storm take you by  surprise.  If you are expecting to be at home or at work during an extreme winter weather event, you need to be concerned about losing power, heat, or cell / phone service. Losing one of these three services may create a life threatening situation. Make sure you have a back up plan.

Whether you are at home, on the road or at work, one should always have an emergency kit. An emergency kit should include the following: a flashlight and extra batteries, a battery-powered NOAA Weather Radio, food and water, extra prescriptions, an emergency heat source, first-aid supplies and a cell phone or another way to communicate such as a CB radio or amateur radio unit.  

The best action to take during a winter storm is to stay inside and not travel, unless it is an emergency. 

If you must drive, slow down and allow extra time to reach your destination! Let someone know where you are going and what route you are going to take. If your car gets stuck in a storm, stay in your vehicle! If you leave your vehicle, you could become disoriented quickly if there is wind-driven snow and cold. Run the motor for a total of 10 minutes each hour for heat. While running the motor, open the window a little bit so that fresh air can get into the car to avoid carbon monoxide poisoning. Make sure you clear snow away from the exhaust pipe to avoid gas poisoning. Attach a bright cloth to your car door to draw attention to yourself, and when it stops snowing, raise the hood of your car to indicate to others you need help.

Tuesday

Lake Effect Snow

Lake effect snow is a common weather phenomena in the Great Lakes region. Lake effect snow develops mainly in northern, central and western New York during the late fall and winter months.  When cold, Canadian air moves over Lakes Ontario and Erie, the relatively warm and moist air from the lakes rise quickly, condenses, and forms lake effect snow. 

The direction of the wind is the most important factor of who will see the lake effect snow. Heavy snow could be falling at one location, while the sun may be shining just a mile or two away in either direction. The geography of the land and water is very important. That is why the Tug Hill Plateau in upstate New York is a great example of how topography plays a role in lake effect snow development. The Tug Hill Plateau typically sees over 200 inches of snow per year.

Lake effect snow develops in bands. These bands can produce several feet of snow within a short period of time. From November 17th to 19th, 2014, up to 7 feet of snow fell downwind of Lake Erie just south of Buffalo.

From November 17th to 19th, 2014, up to 7 feet of snow fell downwind of Lake Erie just south of Buffalo.

Courtesy National Weather Service Buffalo, NY

Snow squalls are intense short-lived bands of very heavy snow that often form along arctic fronts. Snow squalls produce blizzard-like or white-out conditions that typically last less than 30 minutes. They produce rapid snowfall accumulations, rapid drop in visibility and flash freeze conditions on our roads. This makes snow squalls very dangerous to motorists. Nationwide, snow squalls can claim hundreds of lives each winter. 

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Take extreme caution while driving through both lake effect snow and snow squalls. Heavy snowfall in general creates very low visibilities. Lake effect snow and snow squalls can be narrow and intense with visibilities dropping quickly to less than a hundred feet without warning. Lake effect snow and snow squalls often have snowfall rates over 2-3 inches per hour. This leads to very hazardous driving conditions. If all possible, do not drive through intense lake effect snow or snow squalls.  

Wednesday

Nor'easters and Other Winter Storms

Over the past few winters, powerful snowstorms developed along the east coast and paralyzed cities across much of the northeast. These winter storms disrupted hundreds of thousands of lives ranging from loss of power to transportation difficulties. 

Large accumulations of snow can be produced by Nor'easters. Smaller more common snowfall events are often generated by systems called Alberta clippers.

Nor'easters are intense low pressure systems that track along the eastern seaboard. Its name comes from mariners that experienced the strong northeast winds associated with these storms, but inland they are known for their heavy snow and at times blizzard conditions. Some memorable Nor'easters in recent years include the President's day Snowstorm of 2003, the Valentine's Day Snowstorm of 2007, and the Blizzard of 2017 which occurred recently. Snowfall rates in a Nor'easter can reach up to 3 to 6 inches per hour which can last for several hours.

Alberta clippers are common to our region bringing a quick round of snow. Alberta clippers are low pressure systems that develop in or near the providence of Alberta, Canada. Alberta clippers move southeast very quickly and typically bring a few to several inches of snow. Their quick movement limits the snow amounts. 

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Thursday

Flooding and Ice Jams

One of our deadliest winter weather hazards is flooding. 

In the state of New York one usually associates snow, ice, and bitter cold with winter. But sometimes nature throws a curve at us with unseasonably warm temperatures, and heavy rain. 

A number of different factors work together to produce floods in winter. When unseasonable warmth comes to the region it will often melt much, if not all of the snow on the ground especially in the lower elevations. The melting snow can saturate the ground and also swell the rivers. If the combination of unseasonably warm temperatures, heavy rain, and snow melt occurs, rivers may rise above their banks producing floods.

Some of our worst winter floods are created by an intense low pressure system that tracks from the Ohio valley northeast, down the Saint Lawrence Valley in Canada. These storms bring a lot of warm and moist air into the region from the Gulf of Mexico and the Atlantic.

Flooding during the winter months can also be caused by ice jams. When river flows increase, water levels rise. Ice is less dense than water, thus ice floats. When enough pressure is applied by the river below, the ice will break. Ice typically breaks into slabs and floats downstream. When the ice interacts with an obstruction such as a bridge, bend in the river, island, or a wide shallow area, the ice will often pile up into an ice jam. The ice jam then prevents water from freely flowing, and forces the water to rise, creating a flood. Ice jams can form any time during the winter season.

Flooding on roads and poor drainage areas can also occur when mounds of plowed snow and ice block grates and storm drains. Standing water can cause dangerous black ice if it freezes. 

Friday

National Weather Service Winter Products

This will provide you with some terms the National Weather Service uses to describe winter weather as well as the definitions of watches, warnings, and advisories issued for winter weather events.

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