A blizzard is a severe snowstorm characterized by strong sustained winds and low visibility, lasting for a prolonged period of time—typically at least three or four hours. A ground blizzard is a weather condition where snow is not falling but loose snow on the ground is lifted and blown by strong winds. Blizzards can have an immense size and usually stretch to hundreds or thousands of kilometres.
Surface weather analysis is a special type of weather map that provides a view of weather elements over a geographical area at a specified time based on information from ground-based weather stations.
The United Kingdom straddles the higher mid-latitudes between 49° and 61°N on the western seaboard of Europe. Since the UK is always in or close to the path of the polar front jet stream, frequent changes in pressure and unsettled weather are typical. Many types of weather can be experienced in a single day.
A subtropical cyclone is a weather system that has some characteristics of both tropical and extratropical cyclones.
A nor'easter, is a large-scale extratropical cyclone in the western North Atlantic Ocean. The name derives from the direction of the winds that blow from the northeast. The term is commonly used in the winter in New England and Atlantic Canada.
A sea breeze or onshore breeze is any wind that blows from a large body of water toward or onto a landmass. By contrast, a land breeze or offshore breeze is any wind that blows from a landmass toward or onto a large body of water. The term offshore wind may refer to any wind over open water. Sea breezes and land breezes are both important factors in coastal regions' prevailing winds.
A high-pressure area, high, or anticyclone, is an area near the surface of a planet where the atmospheric pressure is greater than the pressure in the surrounding regions. Highs are middle-scale meteorological features that result from interplays between the relatively larger-scale dynamics of an entire planet's atmospheric circulation.
In meteorology, a low-pressure area, low area or low is a region where the atmospheric pressure is lower than that of surrounding locations. Low-pressure areas are commonly associated with inclement weather, while high-pressure areas are associated with lighter winds and clear skies. Winds circle anti-clockwise around lows in the northern hemisphere, and clockwise in the southern hemisphere, due to opposing Coriolis forces. Low-pressure systems form under areas of wind divergence that occur in the upper levels of the atmosphere (aloft). The formation process of a low-pressure area is known as cyclogenesis. In meteorology, atmospheric divergence aloft occurs in two kinds of places:
In meteorology, prevailing wind in a region of the Earth's surface is a surface wind that blows predominantly from a particular direction. The dominant winds are the trends in direction of wind with the highest speed over a particular point on the Earth's surface at any given time. A region's prevailing and dominant winds are the result of global patterns of movement in the Earth's atmosphere. In general, winds are predominantly easterly at low latitudes globally. In the mid-latitudes, westerly winds are dominant, and their strength is largely determined by the polar cyclone. In areas where winds tend to be light, the sea breeze/land breeze cycle is the most important cause of the prevailing wind; in areas which have variable terrain, mountain and valley breezes dominate the wind pattern. Highly elevated surfaces can induce a thermal low, which then augments the environmental wind flow.
A southerly buster is the colloquial name of an abrupt southerly wind change in the southern regions of New South Wales and Victoria, Australia, which approaches from the southeast, mainly on a hot day, bringing in cool, usually severe weather and a dramatic temperature drop, thus ultimately replacing and relieving the prior hot conditions. Marking the boundary between hot and cool air masses, a southerly buster is sometimes represented by a roll-up cloud perpendicular to the coast, which appears from the south and coexists with the wind change, though sometimes there is little visual signal of the southerly's arrival.
The East Asian Monsoon is a monsoonal flow that carries moist air from the Indian Ocean and Pacific Ocean to East Asia. It affects approximately one-third of the global population, influencing the climate of Japan, the Korean Peninsula, Taiwan, China, the Philippines and Mainland Southeast Asia but most significantly Vietnam. It is driven by temperature differences between the East Asian continent and the Pacific Ocean. The East Asian monsoon is divided into a warm and wet summer monsoon and a cold and dry winter monsoon. This cold and dry winter monsoon is responsible for the aeolian dust deposition and pedogenesis that resulted in the creation of the Loess Plateau. The monsoon influences weather patterns as far north as Siberia, causing wet summers that contrast with the cold and dry winters caused by the Siberian High, which counterbalances the monsoon's effect on northerly latitudes.
A subtropical front is a surface water mass boundary or front, which is a narrow zone of transition between air masses of contrasting density, air masses of different temperatures or different water vapour concentrates. It is also characterized by an unforeseen change in wind direction, and speed across its surface between water systems, which are based on temperature and salinity. The subtropical separates the more saline subtropical waters from the fresher sub-Antarctic waters.
The climate of the north and central parts of the U.S. state of Florida is humid subtropical. South Florida has a tropical climate. There is a defined rainy season from May through October when air mass thundershowers that build in the heat of the day drop heavy but brief summer rainfall.
The climate of the United States varies due to changes in latitude, and a range of geographic features, including mountains and deserts. Generally, on the mainland, the climate of the U.S. becomes warmer the further south one travels, and drier the further west, until one reaches the West Coast.
North Carolina's climate varies from the Atlantic coast in the east to the Appalachian Mountain range in the west. The mountains often act as a "shield", blocking low temperatures and storms from the Midwest from entering the Piedmont of North Carolina.
The climate of Massachusetts is mainly a humid continental climate, with hot, humid summers and cold, snowy winters and abundant precipitation. Massachusetts is a state located in the New England region of the northeastern United States. Most of its population of 7.0 million live in the Boston metropolitan area. The eastern half of this relatively small state is mostly urban and suburban. Massachusetts is the most populous of the six New England states and ranks third in the nation by population density and fourth by GDP per capita. Massachusetts receives about 43 inches or 1,090 millimetres of rain annually, fairly evenly distributed throughout the year, slightly wetter during the winter. Summers are warm with average high temperatures in July above 80 °F or 26.7 °C and overnight lows above 60 °F or 15.6 °C common throughout the state. Winters are cold, but generally less extreme on the coast with high temperatures in the winter averaging above freezing even in January, although areas further inland are much colder. The state does have extreme temperatures from time to time with 100 °F or 37.8 °C in the summer and temperatures below 0 °F or −17.8 °C in the winter not being unusual.
The Gulf Stream is a warm and swift Atlantic ocean current that originates in the Gulf of Mexico and flows through the Straits of Florida and up the eastern coastline of the United States, then veers east near 36°N latitude and moves toward Northwest Europe as the North Atlantic Current. The process of western intensification causes the Gulf Stream to be a northward-accelerating current off the east coast of North America. Around 40°0′N30°0′W, it splits in two, with the northern stream, the North Atlantic Drift, crossing to Northern Europe and the southern stream, the Canary Current, recirculating off West Africa.
The 2013–14 North American winter was one of the most significant for the United States, due in part to the breakdown of the polar vortex in November 2013, which allowed very cold air to travel down into the United States, leading to an extended period of very cold temperatures. The pattern continued mostly uninterrupted throughout the winter and numerous significant winter storms affected the Eastern United States, with the most notable one being a powerful winter storm that dumped ice and snow in the Southeastern United States and the Northeastern United States in mid-February. Most of the cold weather abated by the end of March, though a few winter storms did affect the Western United States towards the end of the winter.
The 2014–15 North American winter was frigid and prolifically wintry, especially across the eastern half of North America in the months of January–March. The season began early, with many places in North America experiencing their first wintry weather during mid-November. A period of below-average temperatures affected much of the contiguous United States, and several records were broken. An early trace of snowfall was recorded in Arkansas. There were greater accumulations of snow across parts of Oklahoma as well. A quasi-permanent phenomenon referred to as the polar vortex may have been partly responsible for the cold weather. Temperatures in much of the United States dropped 15 to 35 °F below average by November 19, following a southward "dip" of the polar vortex into the eastern two-thirds of the country. The effects of this dip were widespread, bringing about temperatures as low as 28 °F (−2 °C) in Pensacola, Florida. Following a significant snowstorm there, Buffalo, New York received several feet of snow from November 17–21. In addition, significant winter weather occurred throughout the season, including a major blizzard that struck the Northeastern United States at the end of January, another blizzard that affected much of the Northern United States days later in early February, and several significant snow events paired with very frigid temperatures for much of February.
The southeast Australian foehn is a westerly foehn wind and a rain shadow effect that usually occurs on the coastal plain of southern New South Wales, and as well as in southeastern Victoria and eastern Tasmania, on the leeward side of the Great Dividing Range. Ranging from cool to hot, the effect occurs when westerly winds descend steeply from the Great Dividing Range onto the coastal slopes, whereby causing major adiabatic compression and a substantial loss of moisture.
