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Gary S. Wojcik and Daniel S. Wilks

SEPTEMB[SR 1992 NOTES AND CORRESPONDENCE 501Temperature Forecast Biases Associated with Snow Cover in the Northeast GARY S. WOJCIK* AND DANIEL S. WILKSDepartment of Soil, Crop and Atmospheric Sciences, Cornell University, Ithaca, New York13 July 1991 and 17 April 1992ABSTRACT The sensitivity of temperature forecast biases to the presence or absence of snow cover is investigated for theDecember-March periods of 1985

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Ralph A. Petersen and James E. Hoke

JUNE 1989 NMC NOTES 253The Effect of Snow Cover on the Regional Analysis and Forecast System (RAFS) Low-Level Forecasts RALPH A. PETERSEN AND JAMES E. HOKE NOAA /NWS/NMC/Development Division, Washington, D.C. 26 April 1989 and 27 April 1989ABSTRACT The response of the Regional Analysis and Forecast System (RAFS) low-level forecast fields

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Andrew W. Ellis and Daniel J. Leathers

1. Introduction At its peak in winter, snow covers approximately 46% of the land surface in the Northern Hemisphere, or about 46 million km 2 ( Robinson et al. 1995b ). Large changes in snow cover extent can modify atmospheric conditions through much of the earth’s troposphere due to the radiative effects of snow. Studies have indicated that snow cover can lower surface air temperatures over timescales of days to months by increasing the surface albedo and through the latent heat of melting (e

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Baoqiang Tian and Ke Fan

predictability of the winter NAO has been examined from the perspective of lagged North Atlantic SST anomalies, which are significantly correlated to the next winter’s NAO indices ( Saunders and Qian 2002 ). In terms of atmospheric predictability, analysis has shown that significant links exist between wintertime NAO and SST anomalies in the preceding spring, summer, and autumn ( Rodwell and Folland 2002 ). Meanwhile, Eurasian snow cover is also a predictor when forecasting winter NAO. Early season snow

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Theodore W. Letcher, Sandra L. LeGrand, and Christopher Polashenski

snowfall that preceded the blowing snow event. Fig . 1. WRF domains illustrating the WRF land cover classification. Additional relevant WRF parameterization choices are provided in Table 1 . Table 1. WRF Model physical parameterizations. b. Blowing snow visibility model Generally, blowing snow models treat saltation and turbulent suspension as distinct processes linked through empirical and semiempirical formulas. Typically, these models compute saltation Q s as a streamwise mass flux (kg m −1 s

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James J. Simpson, Michael D. Dettinger, Frank Gehrke, Timothy J. McIntire, and Gary L. Hufford

)]. Winds, temperatures, and other climatic conditions, during and between storms, also vary erratically in high-mountain environments ( Greenland and Losleben 2001 ). Spatial accumulations of snow depend on the original precipitation distribution and on the distributions of shelter from winds and thermal conditions across the landscape. As a result, snow cover and thickness vary from windswept clearings (fell fields) to snow beds of considerable depth over distances ranging from meters to kilometers

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Steven C. Albers, John A. McGinley, Daniel L. Birkenheuer, and John R. Smart

- cipitation type, concentration, and accumulation. Results from validating the cloud fields against independent data obtained during the Winter Icing and Storms Project are presented. Forecasters can now make use of these analyses in a variety of situations, such as depicting sky cover and radiation characteristics over a region, three-dimensionally delineating visibility and icing conditions for aviation, depicting precipitation type, rain and snow accumulation, etc. 1. Introduction New data

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Louis Michael Schoenberger

contrast to lake-wannedair over southwest Michigan. As a result of this intensification, the cold air pushed northward as a densitycurrent or land breeze. Eventually, radiationally cooled air would cover all of western Lower Michigan.1. Introduction The winter land breeze is a frequent phenomenonin western Lower Michigan, where the temperaturecontrast between the relatively warm waters of LakeMichigan and the cold, snow-covered ground can exceed 30-C. The land breeze is most pronounced whenskies

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Gary M. Lackmann, Kermit Keeter, Laurence G. Lee, and Michael B. Ek

temperature was well below freezing, a larger fraction of the latent heat released by freezing rain would go to warming the soil relative to a case in which only a shallow layer of soil was below freezing. During a freezing-rain event that was taking place over a snow-covered surface, the heat flux into or out of the soil would be mitigated by the insulating influence of the snowpack. To provide a quantitative estimate of the importance of latent heat released by freezing rain to near-surface temperatures

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Heather Dawn Reeves, Kimberly L. Elmore, Geoffrey S. Manikin, and David J. Stensrud

around the Bonneville Basin that are not discussed herein. All stations near the center or west side of the basin have a nighttime warm bias, similar to that noted for KENV and DPG17, stations along the east sidewall of the basin that are, in reality, located on the basin floor, but in the model are located on the slope, have a daytime cold and nighttime warm bias similar to that at KSLC, and all stations considered at higher elevations, outside of the basin and in snow-covered areas, have a daytime

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