Monday, November 3, 2014

Wild Windy Wintry Weekend

A rapidly deepening upper level trough brought three days of wild weather to the eastern half of the country from the end of last week through this weekend.

An intensifying surface low and cold front brought cold, windy, and snowy weather to much of the eastern Midwest on Thursday and Halloween.
 

500 millibar map (left) and surface map (right) for 7:00 a.m. CDT October 31, 2014

Winds gusted to 69 mph in Gary, IN on Friday and 67 mph at the Chicago Harrison-Dever Crib and Michigan City, IN.  Wind damage was common, and the winds drove large waves from Lake Michigan onto Lake Shore Drive in Chicago and caused damage to Chicago's lakefront bike path. Heavy snow fell in northern Wisconsin and the Michigan U.P. and measurable snow was recorded as far south as northern Illinois and Indiana. Snow showers occurred even farther south through central Illinois and Indiana.

Snowfall in northern Wisconsin and part of the Michigan U.P. as of the morning of October 31
 The mid-lake south buoy, located about 43 miles east of Milwaukee recorded a wave height of 21.7 feet.  This was tied for the second highest wave height on record at the south buoy, after only 22.9 feet on September 30, 2011.

Snow in Asheville, NC
Photo by Mike Palecki
As the upper level trough deepened a second low developed over western South Carolina, with another low off the Virginia coast Friday night. Plenty of moisture and now cold air was available to the low over South Carolina and heavy snow fell in the Appalachians. Snow piled up to 22 inches in both Spring Creek, NC and Gatlinburg, TN. Measurable and often heavy snow accumulated in higher elevations of Kentucky, Tennessee, Georgia, South Carolina, North Carolina, Virginia, and West Virginia.




500 millibar map (left) and surface map (right) for8:00 a.m. EDT November 1, 2014
Snow in Morristown, TN.  Photo by the NWS Morristown

By midday Saturday the South Carolina low moved out over the Atlantic while continuing to intensify. By late afternoon it began to merge with a second low to its north. By 1:00 a.m. EST on Sunday morning the low was located east of Norfolk, VA at pressure had dropped to 988 millibars. Twelve hours later (1:00 p.m. EST) the strong storm was centered east of Nantucket, MA.

500 millibar map (left) and surface map (right) for 7:00 a.m. EST November 2, 2014

Some snow fell in Massachusetts, but the heaviest snow on Sunday (10 to 21 inches) fell in the eastern portions of Maine. Bangor (12 inches) and Caribou (10.1 inches), ME both set their record earliest day (November 2) with snowfall 10 inches or more. The largest snow accumulation was 21 inches in Cary, ME near the Canadian border. The heavy wet snow and howling winds brought down power lines cutting off power for 130,000 customers. Power may be out in some areas several days.

72 hour snowfall accumulation ending the morning of November 3.