Weather Bug

Sunday, December 26, 2010

2 PM EST, December 26, 2010

Posted by ILIAS at 12:35 PM

East Coast Blizzard Ruining Holiday Travel By WeatherBug Sr. Meteorologist, James West
	Related Content New York City Interactive Radar Boston Interactive Radar United States Alert Map Your Photos The East Coast blizzard targeting the East Coast will cause massive travel problems as the Christmas holiday weekend concludes today. The first of many waves of snow is starting to fall across the immediate East Coast and will continue to spread inland. Later this afternoon and through tonight, the heaviest snow will spread across the I-95 corridor from just around Baltimore all of the way to Boston. Wilmington, Del., Philadelphia, Trenton and Newark, N.J., New York City, southern New England and Boston will all be hit by heavy snow and high winds. Blizzard conditions are likely as winds gust above 35 mph, causing white-out conditions tonight and Monday. States of Emergencies have already been declared in Philadelphia and Boston, resulting in the cancellation of the Eagles-Vikings with more cities and states likely to issue them throughout today. Drivers on I-95, the New Jersey Turnpike, Atlantic City Expressway and the Garden State Parkway, I-80 across northern New Jersey, and I-84 in New England will see conditions deteriorate rapidly this afternoon. Eastern travelers should not start heading to their destination if they do not think they can make it before the heavy snow starts this afternoon. Flights in and out of the major East Coast airports are also being delayed or cancelled starting later this afternoon and evening. Travelers should check with their airlines for the latest information on flights. Most airlines are waiving cancellation and change fees. Amtrak has cancelled trains between Richmond, Va., and Washington today. Trains are running on time between Washington and Boston as of lunchtime Sunday, however delays are likely as the snow hits the busy Northeast Corridor later this evening and tonight. Amtrak passengers will need to check for cancellations. Be sure to keep your WeatherBug active to receive the latest on the latest on the developing East Coast blizzard. Get the latest updates anywhere on Twitter at WeatherBug WeatherBuzz. What do you think of this story? Click here for comments or suggestions.

0 comments:

Cause

On Earth, common weather phenomena include wind, cloud, rain, snow, fog and dust storms. Less common events include natural disasters such as tornadoes, hurricanes, typhoons and ice storms. Almost all familiar weather phenomena occur in the troposphere (the lower part of the atmosphere).[3] Weather does occur in the stratosphere and can affect weather lower down in the troposphere, but the exact mechanisms are poorly understood.[5]

Weather occurs primarily due to density (temperature and moisture) differences between one place to another. These differences can occur due to the sun angle at any particular spot, which varies by latitude from the tropics. In other words, the farther from the tropics you lie, the lower the sun angle is, which causes those locations to be cooler due to the indirect sunlight.[6] The strong temperature contrast between polar and tropical air gives rise to the jet stream.[7] Weather systems in the mid-latitudes, such as extratropical cyclones, are caused by instabilities of the jet stream flow (see baroclinity).[8] Weather systems in the tropics, such as monsoons or organized thunderstorm systems, are caused by different processes.

Because the Earth's axis is tilted relative to its orbital plane, sunlight is incident at different angles at different times of the year. In June the Northern Hemisphere is tilted towards the sun, so at any given Northern Hemisphere latitude sunlight falls more directly on that spot than in December (see Effect of sun angle on climate).[9] This effect causes seasons. Over thousands to hundreds of thousands of years, changes in Earth's orbital parameters affect the amount and distribution of solar energy received by the Earth and influence long-term climate. (see Milankovitch cycles).[10]

The uneven solar heating (the formation of zones of temperature and moisture gradients, or frontogenesis) can also be due to the weather itself in the form of cloudiness and precipitation.[11] Higher altitudes are cooler than lower altitudes, which is explained by the lapse rate.[12][13] On local scales, temperature differences can occur because different surfaces (such as oceans, forests, ice sheets, or man-made objects) have differing physical characteristics such as reflectivity, roughness, or moisture content.

Surface temperature differences in turn cause pressure differences. A hot surface heats the air above it and the air expands,lowering the air pressure and its density.[14] The resulting horizontal pressure gradient accelerates the air from high to low pressure, creating wind, and Earth's rotation then causes curvature of the flow via the Coriolis effect.[15] The simple systems thus formed can then display emergent behaviour to produce more complex systems and thus other weather phenomena. Large scale examples include the Hadley cell while a smaller scale example would be coastal breezes.

The atmosphere is a chaotic system, so small changes to one part of the system can grow to have large effects on the system as a whole.[16] This makes it difficult to accurately predict weather more than a few days in advance, though weather forecasters are continually working to extend this limit through the scientific study of weather, meteorology. It is theoretically impossible to make useful day-to-day predictions more than about two weeks ahead, imposing an upper limit to potential for improved prediction skill.[17]

Modification

The aspiration to control the weather is evident throughout human history: from ancient rituals intended to bring rain for crops to the U. S. Military Operation Popeye, an attempt to disrupt supply lines by lengthening the North Vietnamese monsoon. The most successful attempts at influencing weather involve cloud seeding; they include the fog- and low stratus dispersion techniques employed by major airports, techniques used to increase winter precipitation over mountains, and techniques to suppress hail.[41] A recent example of weather control was China's preparation for the 2008 Summer Olympic Games. China shot 1,104 rain dispersal rockets from 21 sites in the city of Beijing in an effort to keep rain away from the opening ceremony of the games on August 8, 2008. Guo Hu, head of the Beijing Municipal Meteorological Bureau (BMB), confirmed the success of the operation with 100 millimeters falling in Baoding City of Hebei Province, to the southwest and Beijing's Fangshan District recording a rainfall of 25 millimeters.[42]

Whereas there is inconclusive evidence for these techniques' efficacy, there is extensive evidence that human activity such as agriculture and industry results in inadvertent weather modification:[41]

* Acid rain, caused by industrial emission of sulfur dioxide and nitrogen oxides into the atmosphere, adversely effects freshwater lakes, vegetation, and structures.
* Anthropogenic pollutants reduce air quality and visibility.
* Climate change caused by human activities that emit greenhouse gases into the air is expected to affect the frequency of extreme weather events such as drought, extreme temperatures, flooding, high winds, and severe storms.[43]

The effects of inadvertent weather modification may pose serious threats to many aspects of civilization, including ecosystems, natural resources, food and fiber production, economic development, and human health.[44

Forecasting

Weather forecasting is the application of science and technology to predict the state of the atmosphere for a future time and a given location. Human beings have attempted to predict the weather informally for millennial, and formally since at least the nineteenth century.[25][26] Weather forecasts are made by collecting quantitative data about the current state of the atmosphere and using scientific understanding of atmospheric processes to project how the atmosphere will evolve.[27]

Once an all-human endeavor based mainly upon changes in barometric pressure, current weather conditions, and sky condition,[28][29] forecast models are now used to determine future conditions. Human input is still required to pick the best possible forecast model to base the forecast upon, which involves pattern recognition skills, teleconnections, knowledge of model performance, and knowledge of model biases. The chaotic nature of the atmosphere, the massive computational power required to solve the equations that describe the atmosphere, error involved in measuring the initial conditions, and an incomplete understanding of atmospheric processes mean that forecasts become less accurate as the difference in current time and the time for which the forecast is being made (the range of the forecast) increases. The use of ensembles and model consensus helps to narrow the error and pick the most likely outcome.[30][31][32]

There are a variety of end users to weather forecasts. Weather warnings are important forecasts because they are used to protect life and property.[33] Forecasts based on temperature and precipitation are important to agriculture,[34][35][36][37] and therefore to commodity traders within stock markets. Temperature forecasts are used by utility companies to estimate demand over coming days.[38][39][40] On an everyday basis, people use weather forecasts to determine what to wear on a given day. Since outdoor activities are severely curtailed by heavy rain, snow and the wind chill, forecasts can be used to plan activities around these events, and to plan ahead and survive them.

References

# ^ Merriam-Webster Dictionary. Weather. Retrieved on 2008-06-27.
# ^ Glossary of Meteorology. Hydrosphere. Retrieved on 2008-06-27.
# ^ a b Glossary of Meteorology. Troposphere. Retrieved on 2008-06-27.
# ^ "Climate". Glossary of Meteorology. American Meteorological Society. http://amsglossary.allenpress.com/glossary/search?id=climate1. Retrieved 2008-05-14.
# ^ O'Carroll, Cynthia M. (2001-10-18). "Weather Forecasters May Look Sky-high For Answers". Goddard Space Flight Center (NASA). http://www.gsfc.nasa.gov/topstory/20011018windsurface.html.
# ^ NASA. World Book at NASA: Weather. Retrieved on 2008-06-27.
# ^ John P. Stimac. Air pressure and wind. Retrieved on 2008-05-08.
# ^ Carlyle H. Wash, Stacey H. Heikkinen, Chi-Sann Liou, and Wendell A. Nuss. A Rapid Cyclogenesis Event during GALE IOP 9. Retrieved on 2008-06-28.
# ^ Windows to the Universe. Earth's Tilt Is the Reason for the Seasons! Retrieved on 2008-06-28.
# ^ Milankovitch, Milutin. Canon of Insolation and the Ice Age Problem. Zavod za Udz̆benike i Nastavna Sredstva: Belgrade, 1941. Isbn=8617066199.
# ^ Ron W. Przybylinski. The Concept of Frontogenesis and its Application to Winter Weather Forecasting. Retrieved on 2008-06-28.
# ^ Mark Zachary Jacobson (2005). Fundamentals of Atmospheric Modeling (2nd ed.). Cambridge University Press. ISBN 0-521-83970-X. OCLC 243560910.
# ^ C. Donald Ahrens (2006). Meteorology Today (8th ed.). Brooks/Cole Publishing. ISBN 0-495-01162-2. OCLC 224863929.
# ^ Michel Moncuquet. Relation between density and temperature. Retrieved on 2008-06-28.
# ^ Encyclopedia of Earth. Wind. Retrieved on 2008-06-28.
# ^ Spencer Weart. The Discovery of Global Warming. Retrieved on 2008-06-28.
# ^ [1]
# ^ NASA. NASA Mission Finds New Clues to Guide Search for Life on Mars. Retrieved on 2008-06-28.
# ^ West Gulf River Forecast Center. Glossary of Hydrologic Terms - E. Retrieved on 2008-06-28.
# ^ James P. Delgado. Relics of the Kamikaze. Retrieved on 2008-06-28.
# ^ Mike Strong. Fort Caroline National Memorial. Retrieved on 2008-06-28.
# ^ Anthony E. Ladd, John Marszalek, and Duane A. Gill. The Other Dispora: New Orleans Student Evacuation Impacts and Responses Surrounding Hurricane Katrina. Retrieved on 2008-03-29.
# ^ "Famine in Scotland: The 'Ill Years' of the 1690s". Karen Cullen,Karen J. Cullen (2010). Edinburgh University Press. p.21. ISBN 0748638873
# ^ C. W. B. Norand. Effect of High Temperature, Humidity, and Wind on the Human Body. Retrieved on 2008-06-28.
# ^ Mistic House. Astrology Lessons, History, Predition, Skeptics, and Astrology Compatibility. Retrieved on 2008-01-12.
# ^ Eric D. Craft. An Economic History of Weather Forecasting. Retrieved on 2007-04-15.
# ^ NASA. Weather Forecasting Through the Ages. Retrieved on 2008-05-25.
# ^ Weather Doctor. Applying The Barometer To Weather Watching. Retrieved on 2008-05-25.
# ^ Mark Moore. Field Forecasting - A Short Summary. Retrieved on 2008-05-25.
# ^ Klaus Weickmann, Jeff Whitaker, Andres Roubicek and Catherine Smith. The Use of Ensemble Forecasts to Produce Improved Medium Range (3-15 days) Weather Forecasts. Retrieved on 2007-02-16.
# ^ Todd Kimberlain. Tropical cyclone motion and intensity talk (June 2007). Retrieved on 2007-07-21.
# ^ Richard J. Pasch, Mike Fiorino, and Chris Landsea. TPC/NHC’S REVIEW OF THE NCEP PRODUCTION SUITE FOR 2006. Retrieved on 2008-05-05.
# ^ National Weather Service. National Weather Service Mission Statement. Retrieved on 2008-05-25.
# ^ Blair Fannin. Dry weather conditions continue for Texas. Retrieved on 2008-05-26.
# ^ Dr. Terry Mader. Drought Corn Silage. Retrieved on 2008-05-26.
# ^ Kathryn C. Taylor. Peach Orchard Establishment and Young Tree Care. Retrieved on 2008-05-26.
# ^ Associated Press. After Freeze, Counting Losses to Orange Crop. Retrieved on 2008-05-26.
# ^ The New York Times. FUTURES/OPTIONS; Cold Weather Brings Surge In Prices of Heating Fuels. Retrieved on 2008-05-25.
# ^ BBC. Heatwave causes electricity surge. Retrieved on 2008-05-25.
# ^ Toronto Catholic Schools. The Seven Key Messages of the Energy Drill Program. Retrieved on 2008-05-25.
# ^ a b American Meteorological Society
# ^ Huanet, Xin (2008-08-09). "Beijing disperses rain to dry Olympic night". Chinaview. http://news.xinhuanet.com/english/2008-08/09/content_9079637.htm. Retrieved 2008-08-24.
# ^ Intergovernmental Panel on Climate Change
# ^ Intergovernmental Panel on Climate Change
# ^ Global Measured Extremes of Temperature and Precipitation. National Climatic Data Center. Retrieved on 2007-06-21.
# ^ Glenn Elert. Hottest Temperature on Earth. Retrieved on 2008-06-28.
# ^ Glenn Elert. Coldest Temperature On Earth. Retrieved on 2008-06-28.
# ^ Canadian Climate Normals 1971-2000 - Eureka
# ^ Britt, Robert Roy (2001-03-06). "The Worst Weather in the Solar System". Space.com. http://www.space.com/scienceastronomy/solarsystem/solar_system_weather_010306-1.html.
# ^ M. Fulchignoni, F. Ferri, F. Angrilli, A. Bar-Nun, M.A. Barucci, G. Bianchini, W. Borucki, M. Coradini, A. Coustenis, P. Falkner, E. Flamini, R. Grard, M. Hamelin, A.M. Harri, G.W. Leppelmeier, J.J. Lopez-Moreno, J.A.M. McDonnell, C.P. McKay, F.H. Neubauer, A. Pedersen, G. Picardi, V. Pirronello, R. Rodrigo, K. Schwingenschuh, A. Seiff, H. Svedhem, V. Vanzani and J. Zarnecki (2002). "The Characterisation of Titan's Atmospheric Physical Properties by the Huygens Atmospheric Structure Instrument (Hasi)". Space Science Review 104: 395–431. doi:10.1023/A:1023688607077.
# ^ Jet Propulsion Laboratory. OVERVIEW - Climate: The Spherical Shape of the Earth: Climatic Zones. Retrieved on 2008-06-28.
# ^ Anne Minard. Jupiter's "Jet Stream" Heated by Surface, Not Sun. Retrieved on 2008-06-28.
# ^ ESA: Cassini-Huygens. The jet stream of Titan. Retrieved on 2008-06-28.
# ^ Georgia State University. The Environment of Venus. Retrieved on 2008-06-28.
# ^ Ellen Cohen. "Jupiter's Great Red Spot". Hayden Planetarium. http://haydenplanetarium.org/resources/ava/page/index.php?file=P0413jupispot. Retrieved 2007-11-16.
# ^ Suomi, V. E.; Limaye, S. S.; Johnson, D. R. (1991). "High Winds of Neptune: A possible mechanism". Science (AAAS (USA)) 251 (4996): 929–932. doi:10.1126/science.251.4996.929. PMID 17847386.
# ^ Sromovsky, Lawrence A. (1998-10-14). "Hubble Provides a Moving Look at Neptune's Stormy Disposition". HubbleSite. http://hubblesite.org/newscenter/newsdesk/archive/releases/1998/34/text/.
# ^ Knutson, Heather A.; David Charbonneau, Lori E. Allen, Jonathan J. Fortney, Eric Agol, Nicolas B. Cowan, Adam P. Showman, Al, Curtis S. Cooper & S. Thomas Megeath (10 May 2007). "A map of the day–night contrast of the extrasolar planet HD 189733b". Nature 447 (7141): 183–186. doi:10.1038/nature05782. PMID 17495920. http://www.nature.com/nature/journal/v447/n7141/abs/nature05782.html.
# ^ Bill Christensen. Shock to the (Solar) System: Coronal Mass Ejection Tracked to Saturn. Retrieved on 2008-06-28.
# ^ AlaskaReport. What Causes the Aurora Borealis? Retrieved on 2008-06-28.
# ^ Rodney Viereck. Space Weather: What is it? How Will it Affect You? Retrieved on 2008-06-28.

Weather Bug

Sunday, December 26, 2010

2 PM EST, December 26, 2010

0 comments:

Post a Comment

www.yahoobest.com

Cause

Modification

Forecasting

About Me

Blog Archive

Yahoo! Weather - Dhaka, BG

BBC - Weather Centre - Latest Observations for Dhaka, Bangladesh

Yahoo! Weather - Gifu, JA

References