Winter Weather Watch 2014-2015: Winter Storm Astro and Long-Lasting Arctic Cold

By Tom Niziol 
Published: November 10, 2014

http://www.wunderground.com/news/winter-weather-watch-2014-2015-20140930

Welcome to the Winter Weather Watch, your daily briefing on winter weather threats across the nation, by winter weather expert Tom Niziol. Bookmark this page and check back for regular updates through spring 2015.

Below is the latest forecast discussion from Tom Niziol, as well as links to jump to the latest forecast and current maps and our list of the 2014-2015 winter storm names. You can either scroll down the page, or click on these links to jump to your section of interest.

- Snowfall forecast: Map showing forecast snowfall totals over the next 48 hours.
- Latest winter radar: See where any snow, freezing rain or sleet is falling now.
- Where's the cold: Current temperatures showing chilly areas.
- Winter storm names: The entire list of names this season and the science behind how we name them.

Winter Storm Astro
Astro is producing snow over parts of the northern Plains and Upper Midwest and is kicking into full gear. Astro is a product from an interaction of a wave of low pressure and the southward push of an arctic cold front, resulting in accumulating snow. Snow continues to spread across South Dakota and much central and eastern Minnesota to northern sections of Wisconsin and Michigan.

Rapid City area will see 3+" of snow today (on top of a thin layer of ice) with winds 25-30 mph in gusts and falling temperatures (wind chills near 0 by evening). Snowfall of 8" is possible around the Twin Cities area (heavier in counties to the north and northeast) to northern Wisconsin and the Upper Peninsula of Michigan. Parts of northern Wisconsin should see double digit snowfall. Amounts of 18"+ possible in higher elevations south of Lake Superior due to lake enhancement. Road and air transportation issues likely.

The storm winds down in the upper Great Lakes later Tuesday. Bands of lake-effect snow should set up across the northern Great Lakes by late Tuesday night and this will translate eastward to the eastern Great Lakes by Wednesday night and Thursday, continuing into Friday off of Lakes Erie and Ontario. A few inches of lake-effect snow are possible here and there but this doesn't look like a major event at this time.

Arctic Air Invasion/Relentless Cold
Arctic air had descended upon the US. It will spread eastward and southward and it will be of long duration. The expansiveness and longevity of this cold outbreak is extremely rare for November. Many Midwest and southern cities will have lows below freezing for more than a week and high temperatures below the average daily high for ANY day. More like January average highs.

Temperature departures greater than 30-35 degrees colder than average will be in play across the western Plains, then 10 to 20 degrees below average around the Appalachians by Thursday. Current forecast temperatures and departures for midweek are shown below. Low temperatures will likely dip below zero over parts of Montana and the western Dakotas by midweek and single digit lows (6 degrees) around the Twin Cities AM Friday as another surge of cold air pours into the northern tier of states.

Snowfall Forecast

Latest Winter Radar

Current Temperatures

2014-2015's Winter Storm Names

In an effort to increase awareness and enhance communication of disruptive, impactful winter storms, The Weather Channel named winter storms starting in the 2012-2013 season. We are using a new list of names, shown above, for the 2014-2015 season.

In 2012-2013, there were 27 named winter storms spanning over five months beginning with the post-Sandy Winter Storm Athena in early November and ending with Winter Storm Achilles in early May.

In 2013-2014, there were 26 named winter storms beginning in early October with historic High Plains Winter Storm Atlas and ending with a mid-May Rockies snowstorm, Winter Storm Zephyr.

Not every winter weather system will receive a name. The Weather Channel has specific criteria in place to determine when we name a particular winter storm. Our two main criteria for naming a winter storm are:

• It is forecast to produce conditions that meet the National Weather Service winter-weather warning threshold(s) over a main population center or multiple states, beginning generally within 48 hours.
• It is forecast to produce winter weather conditions that would be historic, especially unusual, or memorable, beginning generally within 48 hours.