A shelf cloud is a low, horizontal wedge-shaped cloud, associated with a thunderstorm gust front (or occasionally with a cold front, even in the absence of thunderstorms). A rising cloud motion often can be seen in the leading part of the shelf cloud, while the underside often appears turbulent, boiling, and wind-torn.
Most false tornado and false funnel cloud reports are associated with shelf clouds. Shelf clouds are low-hanging, horizontal cloud features attached to the front side of lines of storms or even a single storm. Usually there isn't any persistent rotation on a vertical axis within shelf clouds or within individual cloud fragments that extend downward from the shelf cloud, therefore they are just another scary-looking cloud.
Shelf clouds often resemble snow plows, big waves or tsunamis and can be very scary-looking since they are usually low-hanging. Sometimes they may found only a couple hundred feet above the ground. There are two other phenomena that might resemble tornadoes or funnel clouds but are not 1) dark rain shafts or narrow columns of heavy rain, and 2) the white color of a hail shaft, a column of hail extending from the ground to the cloud base, may generate a light-dark contrast with surrounding rain, resulting in what might appear to be a funnel cloud or a tornado to the untrained eye.
Dry conditions and above-normal temperatures are expected for Super Bowl Sunday in Santa Clara, California.
The new week will bring more opportunities for snow to create slick travel in the northeastern United States, starting with a winter storm set to sideswipe New England on Monday.
Cold and snow showers are in store for the New Hampshire primary on Tuesday but should not significantly impact voter turnout.
As the Denver Broncos and Carolina Panthers clash for the Super Bowl 50 title in Santa Clara, California, on Sunday, they will do so in one of the most energy-efficient stadiums in the world.
A magnitude-6.4 earthquake shook southern Taiwan shortly before 4 a.m. local time on Saturday, according to the U.S. Geological Survey.
In some circumstances climate, environmental factors and weather have led to some of the most exciting, mysterious and academically important discoveries of all time.
East Coast (1978)
Massive Northeaster buried East Coast cities - 18 in. NYC, 16 in. Philadelphia, 14 in. Baltimore. Referred to as the blizzard of '78. It was the worst winter storm in coastal New England history. Monumental surf from hurricane force winds battered the coastline. Boston 27.2 in. snow, near 50 in. in NW Rhode Island. 75 deaths. $500 million damage.
Norfolk, VA (1980)
12.4 inches of snow.
Albuquerque, NM (1986)
6 inches of snow.