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Lake Effect Snow Watch
A lake effect snow watch was a bulletin issued by the National Weather Service in the United States to warn of heavy snowfall amounts that will be possible from convective snow generated by cold air masses passing over unfrozen lakes (lake effect snow). The criteria for amounts may vary over different county warning areas. On October 2, 2017, issuance of the Lake Effect Snow Watch has been discontinued, and a winter storm watch is now issued when the above criteria are expected to be met. Example MNZ020-037-181845- /O.NEW.KDLH.LE.A.0004.081219T0600Z-081220T0600Z/ SOUTHERN LAKE/LAKESHORE-CARLTON/SOUTHERN ST. LOUIS- 443 AM CST THU DEC 18 2008 ...LAKE EFFECT SNOW WATCH IN EFFECT FROM LATE TONIGHT THROUGH FRIDAY EVENING... THE NATIONAL WEATHER SERVICE IN DULUTH HAS ISSUED A LAKE EFFECT SNOW WATCH...WHICH IS IN EFFECT FROM LATE TONIGHT THROUGH FRIDAY EVENING.) LAKE EFFECT SNOW WILL DEVELOP AROUND MIDNIGHT TONIGHT...AND LAST THROUGH MUCH OF FRIDAY AND INTO FRIDAY EVENING. THE HEAVI ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Weather Service
The National Weather Service (NWS) is an agency of the United States federal government that is tasked with providing weather forecasts, warnings of hazardous weather, and other weather-related products to organizations and the public for the purposes of protection, safety, and general information. It is a part of the National Oceanic and Atmospheric Administration (NOAA) branch of the Department of Commerce, and is headquartered in Silver Spring, Maryland, within the Washington metropolitan area. The agency was known as the United States Weather Bureau from 1890 until it adopted its current name in 1970. The NWS performs its primary task through a collection of national and regional centers, and 122 local Weather Forecast Offices (WFOs). As the NWS is an agency of the U.S. federal government, most of its products are in the public domain and available free of charge. History Calls for the creation of a government weather bureau began as early as 1844, when the electrica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five major unincorporated territories, nine United States Minor Outlying Islands, Minor Outlying Islands, and 326 Indian reservations. The United States is also in Compact of Free Association, free association with three Oceania, Pacific Island Sovereign state, sovereign states: the Federated States of Micronesia, the Marshall Islands, and the Palau, Republic of Palau. It is the world's List of countries and dependencies by area, third-largest country by both land and total area. It shares land borders Canada–United States border, with Canada to its north and Mexico–United States border, with Mexico to its south and has maritime borders with the Bahamas, Cuba, Russia, and other nations. With a population of over 333 million, it is the List of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snow
Snow comprises individual ice crystals that grow while suspended in the atmosphere An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. ...—usually within clouds—and then fall, accumulating on the ground where they undergo further changes. It consists of frozen crystalline water throughout its life cycle, starting when, under suitable conditions, the ice crystals form in the atmosphere, increase to millimeter size, precipitate and accumulate on surfaces, then metamorphose in place, and ultimately melt, slide or Sublimation (phase transition), sublimate away. Snowstorms organize and develop by feeding on sources of atmospheric moisture and cold air. Snowflakes Nucleation, nucleate around particles in the atmosphere by attracting supercooling, supercooled water droplets, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Mass
In meteorology, an air mass is a volume of air defined by its temperature and humidity. Air masses cover many hundreds or thousands of square miles, and adapt to the characteristics of the surface below them. They are classified according to latitude and their continental or maritime source regions. Colder air masses are termed polar or arctic, while warmer air masses are deemed tropical. Continental and superior air masses are dry, while maritime and monsoon air masses are moist. Weather fronts separate air masses with different density (temperature or moisture) characteristics. Once an air mass moves away from its source region, underlying vegetation and water bodies can quickly modify its character. Classification schemes tackle an air mass' characteristics, as well as modification. Classification and notation The Bergeron classification is the most widely accepted form of air mass classification, though others have produced more refined versions of this scheme over diff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Effect Snow
Lake-effect snow is produced during cooler atmospheric conditions when a cold air mass moves across long expanses of warmer lake water. The lower layer of air, heated up by the lake water, picks up water vapor from the lake and rises up through the colder air above. The vapor then freezes and is deposited on the leeward (downwind) shores. The same effect also occurs over bodies of saline water, when it is termed ocean-effect or bay-effect snow. The effect is enhanced when the moving air mass is uplifted by the orographic influence of higher elevations on the downwind shores. This uplifting can produce narrow but very intense bands of precipitation, which deposit at a rate of many inches of snow each hour, often resulting in a large amount of total snowfall. The areas affected by lake-effect snow are called snowbelts. These include areas east of the Great Lakes in North America, the west coasts of northern Japan, the Kamchatka Peninsula in Russia, and areas near the Great ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
County (United States)
In the United States, a county is an Administrative division, administrative or political subdivision of a U.S. state, state that consists of a geographic region with specific Border, boundaries and usually some level of governmental authority. The term "county" is used in 48 states, while Louisiana and Alaska have functionally equivalent subdivisions called List of parishes in Louisiana, parishes and List of boroughs and census areas in Alaska, boroughs, respectively. The specific governmental powers of counties vary widely between the states, with many providing some level of services to civil townships, Local government in the United States, municipalities, and unincorporated areas. Certain municipalities are List of U.S. municipalities in multiple counties, in multiple counties; New York City is uniquely partitioned into five counties, referred to at the city government level as boroughs of New York City, boroughs. Some municipalities have consolidated with their county gove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Winter Storm Watch
A winter storm watch is issued by the National Weather Service of the United States when there is a possibility of heavy snow or potential of significant ice accumulations, without meeting a specific other winter criteria. The watch is typically issued 12 to 48 hours before the storm's expected arrival in the given area. The criteria for this watch can vary from place to place, which is true with other winter weather warning and advisories. As the event of the storm draws nearer in time and confidence in the occurrence of significant winter weather conditions and accumulation is increased, the weather watch will be upgraded to a winter storm warning or blizzard warning, depending on whether blizzard conditions will be met. If there is considerable confidence in significant ice accumulations with little to no snow, the watch will be upgraded to an ice storm warning. When confidence increases in the occurrence of winter like conditions that are not expected to reach warning or othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Effect Snow Warning
A lake effect snow warning is a bulletin issued by the National Weather Service in the United States to warn of heavy snowfall accumulations that are imminent from convective snow generated by very cold airmass passing over unfrozen lakes (lake effect snow). The criteria for amounts may vary significantly over different county warning areas. On October 2, 2017, some National Weather Service Forecast Offices discontinued issuing the Lake Effect Snow Warning, and consolidated it with the Winter Storm Warning. On October 15, 2018, the National Weather Service discontinued issuing Lake Effect Snow Warnings nationwide all together, and all offices consolidated it with the Winter Storm Warning. Lake effect snow warnings were reinstated for the 2019–20 winter season. Environment Canada's Meteorological Service of Canada issues similar warnings but they are called '' snowsquall warnings''. Examples 879 WWUS41 KBUF 171935 WSWBUF URGENT - WINTER WEATHER MESSAGE National Weathe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snowsquall
A snowsquall, or snow squall, is a sudden moderately heavy snowfall with blowing snow and strong, gusty surface winds. It is often referred to as a whiteout and is similar to a blizzard but is localized in time or in location and snow accumulations may or may not be significant. Types There are two primary types of snowsqualls: lake effect and frontal. Lake-effect snow When arctic air moves over large expanses of warmer open waters in winter, convective clouds develop which cause heavy snow showers due to the large amount of moisture available. This occurs southwest of extratropical cyclones, with the curved cyclonic wind flow bringing cold air across the relatively warm Great Lakes which then leads to narrow lake-effect snow bands that can produce significant localized snowfall. Whiteout conditions will affect narrow corridors from shores to inland areas aligned along the prevailing wind direction. This will be enhanced when the moving air mass is uplifted by higher el ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
