"Chinook winds are most frequent in Montana but are common in Wyoming and Alberta and can occur as far south as Colorado," Anderson said.
The term Chinook is derived from the Native American people who lived in the geographical area from where the wind originates. The Chinook people lived in the vicinity of the Columbia River, which forms the present-day boundary of Washington and Oregon. However, often the brute force of the Chinook wind is not realized until the air flows hundreds of miles farther to the east and over the Rockies.
A 40- to 50-mph wind over the ridges and passes may reach speeds of 80 to 100 mph by the time the air reaches the foothills and High Plains.
The winds described in this case are referred to as Chinook winds.
During a more typical Chinook wind warming event, temperatures may rise 25 to 50 degrees. Occasionally, air that has been warmed by this process can reach thousands of miles across the Mississippi River and into the Eastern states. Report a Typo.
In these cases, Arctic air was quickly eroded by mild air from the Pacific Ocean. Loma, Montana, holds the world record for the greatest 24-hour temperature change.
In the absence of a strong storm, a straight-line jet stream set up from west to east across the nation can be enough to generate a significant Chinook event.
A strong föhn wind can make snow one foot (30 cm) deep almost vanish in one day. The snow partly sublimates and partly melts and evaporates in the dry wind. Chinook winds have been observed to raise winter temperature, often from below −20 °C (−4°F) to as high as 10–20°C (50–68°F) for a few hours or days, then temperatures plummet to their base levels. Chinook winds caused the greatest 24-hour temperature change ever recorded, occurring on 15 January 1972, in Loma, Montana; the temperature rose from −48 to 9°C (−54 to 49°F), an increase of 57°C (103°F).
The reference to a wind or weather system, simply "a Chinook", originally meant a warming wind from the ocean into the interior regions of the Pacific Northwest of the US. A strong föhn wind can make snow one foot (30 cm) deep almost vanish in one day. The snow partly melts and partly sublimates in the dry wind.
Adiabatic warming of downward moving air; this produces the warm föhn wind called a "Chinook". Chinook winds / ʃɪˈnʊk /, or simply Chinooks, are föhn winds in the interior West of North America, where the Canadian Prairies and Great Plains meet various mountain ranges, although the original usage is in reference to wet, ...
Chinook winds have been observed to raise winter temperature, often from below −20 °C (−4°F) to as high as 10–20°C (50–6 8°F) for a few hours or days, then temperatures plummet to their base levels.
The air associated with a coastal Chinook is stable ; this minimizes wind gusts and often keeps winds light in sheltered areas. In exposed areas, fresh gales are frequent during a Chinook, but strong gale- or storm-force winds are uncommon; most of the region's stormy winds come when a fast "westerly" jet stream lets air masses from temperate and subarctic latitudes clash.
Where Chinooks occur most frequently. Chinooks are most prevalent over southern Alberta in Canada, especially in a belt from Pincher Creek and Crowsnest Pass through Lethbridge, which get 30–35 Chinook days per year, on average.
The Chinook can seem to do battle with the Arctic air mass at times. It is not unheard of for people in Lethbridge to complain of −20 °C (−4 °F) temperatures while those in desert region, just 77 km (48 mi) down the road, enjoy 10 °C (50 °F) temperatures. This clash of temperatures can remain stationary, or move back and forth, in the latter case causing such fluctuations as a warm morning, a bitterly cold afternoon, and a warm evening. A curtain of fog often accompanies the clash between warm to the west and cold to the east.
Chinook winds are a weather phenomenon we see quite often in southern Colorado. They are a warm and dry wind that are the result of how the wind interacts with our mountainous terrain. For example, a warm moist air mass sets up west of the Rockies.
This wind is very dry, warm and fast. It can reach speeds of 80 mph.
This can even start to warm up temperatures before sunrise! These winds are sometimes called “snow killers” because they get rid of snow so quickly. As the warm, dry wind passes over snowy ground, it sublimates, ...
The weather moves from west to east, so this air mass will have to travel over the mountains. As it moves up the slope, the air cools, and all the moisture is squeezed out, resulting in showers, storms and snow over the Western Slopes.
By the time the air reaches the eastern side of the Rockies, it is much cooler and dry. The air still has to travel down the slopes. As it moves down in elevation, it has the opposite reaction to traveling upslope. It warms instead of cools. The air warms an average of about 5.5 degrees per 1,000 feet descent.
Weather History: Chinook Winds of Winter 1982. Chinook winds are downsloping, warm, and dry winds that occur on the leeward, or sheltered, side of mountain ranges, such as the Rocky Mountains. Chinook winds are fairly common during the winter months and often bring extreme increases in temperatures to the region as they move from west ...
Chinook winds can be accompanied by beautiful cloud formations, called lenticular clouds , that appear smooth and sculpted Ironically, Chinook winds can be accompanied by beautiful cloud formations, called lenticular clouds, that appear smooth and sculpted, as shown in the top image.
the most severe episodes took place on January 17 and 24, two consecutive Sundays While the Foothills area of southeastern Wyoming and Colorado experienced a number of strong Chinook events in January 1982, the most severe episodes took place on January 17 and 24, two consecutive Sundays.
The strongest wind gust recorded was 140 mph at Wondervu, a record for that normally windy spot. Elsewhere, speeds reached 125 mph at Buckhorn Mountain, 110 at Waverly, and 92 at Boulder.
Chinook winds are the result of air rising over mountain ranges – in this case, the northern Rockies – and as the air reaches the ridge tops, it begins to sink and warm as it descends the mountain slopes.
One of the most extreme examples of warming from a chinook happened in Loma, Montana, Jan. 14-15, 1972. The temperature there warmed from minus 54 degrees to 49 degrees above zero in just 24 hours. That 103-degree temperature rise set a record for the largest 24-hour temperature change in U.S. weather records.
The National Weather Service office in Sioux Falls, South Dakota, described the cause of the dramatic temperature changes: "The wild temperature fluctuations were likely due to cold air and warm air sloshing back and forth along the plains at the base of the Black Hills.
Just before midnight, the low temperature bottomed out at a record of 17 degrees. This is a total drop of 66 degrees from the record high to the record low.
The wind in both locations was from an easterly direction before the temperature rise occurred. That was holding arctic air in place along the Front Range of the northern Rockies. A rapid shift in the wind direction to the west or southwest then occurred and pushed the arctic air away. This type of wind in the northern Rockies is known as ...
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Oklahoma City accomplished a rare feat on Nov. 11, 1911.
The Los Angeles River's official beginning is at the confluence of two channelized streams – Bell Creek and Arroyo Calabasas – in the Canoga Park section of the city of Los Angeles, just east of California State Route 27, at WikiMiniAtlas 34°11′43″N 118°36′07″W / 34.1952°N 118.601838°W / 34.1952; -118.601838 (the east side of Canoga Park High School ).
The river provided a source of water and food for the Tongva people prior to the arrival of the Spanish. After the establishment of Mission San Gabriel in 1771, the Spanish would refer to all of the Tongva living in that mission's vicinity as Gabrieleño.
Sepulveda Basin is a flood-control basin to manage floodwater runoff.
Historically, the native species of fish in the Los Angeles River included rainbow/steelhead trout ( Oncorhynchus mykiss ), river shrimp, Chinook salmon ( Oncorhynchus tshawytscha ), Sacramento pikeminnow ( Ptychocheilus grandis ), Pacific lamprey, three-spined stickleback, and Santa Ana sucker.
The ongoing efforts to revitalize the river began in earnest in approximately 2002. A number of city and county departments, committees and non-profit organizations have led the revitalization efforts.
Springtime flow in 2008 at North Broadway-Buena Vista Viaduct (built 1909–11) on the Los Angeles River near Lincoln Heights.
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