Aoraki / Mount Cook is the highest mountain in New Zealand. Its height, as of 2014, is listed as 3,724 metres. It sits in the Southern Alps, the mountain range that runs the length of the South Island. A popular tourist destination, it is also a favourite challenge for mountain climbers. Aoraki / Mount Cook consists of three summits: from south to north, the Low Peak, the Middle Peak and the High Peak. The summits lie slightly south and east of the main divide of the Southern Alps, with the Tasman Glacier to the east and the Hooker Glacier to the southwest. Mount Cook is ranked 10th in the world by topographic isolation.
Fog is a visible aerosol consisting of tiny water droplets or ice crystals suspended in the air at or near the Earth's surface. Fog can be considered a type of low-lying cloud usually resembling stratus, and is heavily influenced by nearby bodies of water, topography, and wind conditions. In turn, fog affects many human activities, such as shipping, travel, and warfare.
The Southern Alps are a mountain range extending along much of the length of New Zealand's South Island, reaching its greatest elevations near the range's western side. The name "Southern Alps" generally refers to the entire range, although separate names are given to many of the smaller ranges that form part of it.
The mistral is a strong, cold, northwesterly wind that blows from southern France into the Gulf of Lion in the northern Mediterranean. It produces sustained winds averaging 31 miles an hour, sometimes reaching 60 miles an hour. It can last for several days. Periods of the wind exceeding 30 km/h for more than sixty-five hours have been reported. It is most common in the winter and spring, and strongest in the transition between the two seasons.
A Foehn, or Föhn, is a type of dry, relatively warm downslope wind that occurs in the lee of a mountain range. It is a rain shadow wind that results from the subsequent adiabatic warming of air that has dropped most of its moisture on windward slopes. As a consequence of the different adiabatic lapse rates of moist and dry air, the air on the leeward slopes becomes warmer than equivalent elevations on the windward slopes.
Orographic lift occurs when an air mass is forced from a low elevation to a higher elevation as it moves over rising terrain. As the air mass gains altitude it quickly cools down adiabatically, which can raise the relative humidity to 100% and create clouds and, under the right conditions, precipitation.
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. Typically, such storms originate as a low-pressure area that forms within 100 miles (160 km) of the shore between North Carolina and Massachusetts. The precipitation pattern is similar to that of other extratropical storms, although nor'easters are usually accompanied by heavy rain or snow, and can cause severe coastal flooding, coastal erosion, hurricane-force winds, or blizzard conditions. They tend to develop most often and most powerfully between the months of November and March, because of the difference in temperature between the cold polar air mass coming down from central Canada and the warm ocean waters off the upper East Coast. The susceptible regions—the upper north Atlantic coast of the United States and the Atlantic Provinces of Canada—are generally impacted by nor'easters a few times each winter.
A rain shadow is an area of significantly reduced rainfall behind a mountainous region, on the side facing away from prevailing winds, known as its leeward side.
Chinook winds, or simply Chinooks, are two types of prevailing warm, generally westerly winds in western North America: Coastal Chinooks and interior Chinooks. The coastal Chinooks are persistent seasonal, wet, southwesterly winds blowing in from the ocean. The interior Chinooks are occasional warm, dry föhn winds blowing down the eastern sides of interior mountain ranges. The coastal Chinooks were the original term, used along the northwest coast, and the term in the interior of North America is later and derives from the coastal term.
Weather lore is the body of informal folklore related to the prediction of the weather and its greater meaning.
A weather front is a boundary separating air masses for which several characteristics differ, such as air density, wind, temperature, and humidity. Disturbed and unstable weather due to these differences often arises along the boundary. For instance, cold fronts can bring bands of thunderstorms and cumulonimbus precipitation or be preceded by squall lines, while warm fronts are usually preceded by stratiform precipitation and fog. In summer, subtler humidity gradients known as dry lines can trigger severe weather. Some fronts produce no precipitation and little cloudiness, although there is invariably a wind shift.
Berg wind is the South African name for a katabatic wind: a hot dry wind blowing down the Great Escarpment from the high central plateau to the coast.
The climate of New Zealand is varied due to the country's diverse landscape. Most regions of New Zealand belong to the temperate zone with a maritime climate characterised by four distinct seasons. Winters are relatively mild and summers comparatively cool. The main contributing factors are the Pacific Ocean and latitude, although the mountain ranges can cause significant climate variations in locations barely tens of kilometres from each other. Conditions vary from extremely wet on the West Coast of the South Island to almost semi-arid in Central Otago and subtropical in Northland.
A cold front is the leading edge of a cooler mass of air at ground level that replaces a warmer mass of air and lies within a pronounced surface trough of low pressure. It often forms behind an extratropical cyclone, at the leading edge of its cold air advection pattern—known as the cyclone's dry "conveyor belt" flow. Temperature differences across the boundary can exceed 30 °C (54 °F) from one side to the other. When enough moisture is present, rain can occur along the boundary. If there is significant instability along the boundary, a narrow line of thunderstorms can form along the frontal zone. If instability is weak, a broad shield of rain can move in behind the front, and evaporative cooling of the rain can increase the temperature difference across the front. Cold fronts are stronger in the fall and spring transition seasons and are weakest during the summer.
A kalbaisakhi, also known in Assam as a bordoisila (বৰদৈচিলা) and in some English publications as a nor'wester, is a localised rainfall and thunderstorm event which occurs in Bangladesh as well as the Indian states of Bihar, Jharkhand, Odisha, Tripura, Assam, and West Bengal during summer. These storms generally occur in the afternoon or just before sunset, when thick dark black clouds start appearing over the sky and then bring gale-speed wind with torrential rain, often with hail, but spanning only a short period of time.
This glossary of meteorology is a list of terms and concepts relevant to meteorology and atmospheric science, their sub-disciplines, and related fields.
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.
The Taieri Pet is a lenticular cloud formation that occurs in the Strath-Taieri region of Otago in the South Island of New Zealand. The cloud formation is created when north-westerly winds are forced upward over the Rock and Pillar Range.
